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F.A.Q.

I. California Cancer Registry Overview: FAQs

I. California Cancer Registry Overview: FAQs 

WHAT DOES THE CALIFORNIA CANCER REGISTRY DO? 

The mission of the California Cancer Registry (CCR) is to serve the public by collecting statewide data, conducting surveillance and research into the causes, controls, and cures of cancer and communicating results to the public.  The CCR monitors the occurrence of cancer among Californians, both incidence (new diagnoses) and mortality (deaths). The CCR, which is operated by the California Department of Public Health and ten regional cancer registries, is an essential tool for the prevention and control of cancer in California. By law (Health and Safety Code, Section 103885), all new cancer cases diagnosed in California residents since January of 1988 have been reported to the CCR, with strict guidelines to maintain patient confidentiality.

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WHAT INFORMATION DOES THE CALIFORNIA CANCER REGISTRY COLLECT?

All data collected by the California Cancer Registry (CCR) are obtained directly from cancer patients’ medical records.  The CCR does not interview patients.

The CCR collects demographic, diagnostic, and treatment information on individual cancer cases.

  • Demographic data include: patient’s name, address at time of diagnosis, sex, race, and age at diagnosis.
  • Diagnostic data include: type of cancer (such as breast cancer) and stage of disease at time of diagnosis.
  • Treatment data include: whether the patient had surgery, radiation, or chemotherapy as the first course of treatment.

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WHAT ARE THE DATA USED FOR?

California Cancer Registry (CCR) data are used to:

  • Monitor the number of new cancer cases and cancer deaths over time;
  • Examine disparities in cancer risk, treatment and survival;
  • Examine treatment choices and other predictors of survival;
  • Measure the success of cancer screening programs;
  • Respond to public concerns and questions about cancer; and
  • Conduct research to find the causes and cures of cancer.

Researchers have used CCR data to:

  • Analyze geographic, racial/ethnic, and occupational differences in cancer risk;
  • Evaluate the quality of medical care received by cancer patients; and
  • Examine patient survival with respect to cancer type, extent of the disease, demographic characteristics, and other important factors.

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WHAT HAS THE CALIFORNIA CANCER REGISTRY ACCOMPLISHED?

The California Cancer Registry (CCR):

  • Is internationally recognized for its high quality data;
  • Receives major grants to investigate the causes, prevention and the cures of cancer;
  • Brings millions of research dollars to California;
  • Provides information on cancer rates among the state’s diverse race/ethnicity groups;
  • Publishes special reports on many cancer types; and
  • Provides the public access to state, regional, and county level cancer incidence and mortality rates plus interactive maps via the internet at www.ccrcal.org.

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CANCER REPORTING IN CALIFORNIA TIMELINE

  • 1947 California Tumor Registry established in selected large hospitals
  • 1960 Alameda County Cancer Registry established as the first population-based cancer registry in California
  • 1969 San Francisco Bay Area Registry included in National Cancer Institute’s (NCI) Third National Cancer Survey
  • 1972 Cancer Surveillance Program (CSP) of Los Angeles County established
  • 1973 San Francisco Bay Area Registry included in NCI’s Surveillance, Epidemiology, and End Results (SEER) Program
  • 1983 Cancer Surveillance Program of Orange County established
  • 1985 California Cancer Reporting Law signed into effect (CCR established)
  • 1988 Population-based cancer reporting initiated statewide
  • 1992 CSP of Los Angeles County included in SEER Program
  • 1997 50 years of cancer reporting in California
  • 2000 Published ten years of complete statewide cancer reporting
  • 2001 Greater California Registry (all regions in California except for San Francisco and Los Angeles) included in SEER Program
  • 2007 20 years of statewide population-based cancer reporting
  • 2009 Published 20 years of complete statewide cancer reporting

 

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HOW DOES THE CALIFORNIA CANCER REGISTRY SAFEGUARD PRIVACY AND ENSURE DATA SECURITY?

The California Cancer Registry (CCR) was established in 1985 to serve as a key resource in the state for research into the causes and cures of cancer.  It has a productive record of using CCR data for research and program evaluation to improve the spectrum of cancer control in California, including prevention, diagnosis, treatment and quality of life.  CCR has very stringent policies and procedures to ensure that cancer data reported are maintained with the highest degree of confidentiality and privacy. 

Cancer researchers must go through a rigorous process to access any CCR data.  The CCR will only release patient contact information to qualified researchers under tightly controlled circumstances where the research has first been approved by the California State Committee for the Protection of Human Subjects (CPHS) Institutional Review Board. Research proposals are evaluated by CPHS to ensure patients’ rights are protected and the research justified. Additionally, a federally approved Institutional Review Board (IRB) at the researcher’s institution must also approve the research proposal.  This IRB will also ensure that patient rights are monitored and protected.

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HIPAA FAQS

 

WHAT IS THE HIPAA PRIVACY RULE?

In 1996 the U.S. Congress passed a law requiring, among other things, uniform federal privacy protections for individually identifiable health information.  This law is called the Health Insurance Portability and Accountability Act of 1996, or “HIPAA.”  The U.S. Department of Health and Human Services issued final regulations implementing the privacy provisions of HIPAA.  These regulations are called the “Privacy Rule.”  Copies of the HIPAA Privacy Rule, as well as helpful explanatory materials, may be found at the HHS Office of Civil Rights website: http://www.hhs.gov/ocr/hipaa.

 

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IS IT A VIOLATION OF HIPAA FOR A COVERED ENTITY TO REPORT INFORMATION ABOUT CASES OF CANCER TO THE CALFORNIA CANCER REGISTRY?

No.  Reporting information about cases of cancer in accordance with the requirements of the California Cancer Registry authorizing statute and regulations is permitted by HIPAA.  The Privacy Rule contains a specific provision authorizing covered entities to disclose protected health information as required by law.  See 45 CFR sec. 164.512(a)(1).  In fact, penalties for failure to comply with state reporting are specified in state law and often consist of significant fines (California Health and Safety Code, Section 103885(f)).
(Note: Covered entities include health plans, health care clearinghouses and health care providers who conduct certain financial and administrative transactions electronically. These electronic transactions are those for which standards have been adopted by the Secretary under HIPAA, such as electronic billing and fund transfers.  More information on covered entities can be found at the HHS website: http://www.hhs.gov/ocr/privacy/hipaa/faq/covered_entities/)

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DOES HIPAA REQUIRE COVERED ENTITIES TO OBTAIN WRITTEN AUTHORIZATION FROM THE INDIVIDUAL BEFORE REPORTING PROTECTED HEALTH INFORMATION TO THE CALIFORNIA CANCER REGISTRY?

No. The provision of the Privacy Rule authorizing disclosure of protected health information as required by law is an exception to the requirement for written authorization. See 45 CFR sec. 164.512(a)(1).

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ARE COVERED ENTITIES REQUIRED TO DETERMINE WHETHER THE INFORMATION ABOUT CASES OF CANCER REPORTED TO THE CALIFORNIA CANCER REGISTRY IS THE "MINIMUM NECESSARY" INFORMATION REQUIRED TO BE DISCLOSED?

No. The Privacy Rule does include a general requirement that covered entities make reasonable efforts to limit the disclosure of protected health information to the minimum necessary to accomplish the intended purpose of the disclosure. See 45 CFR sec. 164.502(b)(1). However, there is a specific exception to this requirement for disclosures that are required by law, such as the reporting of information about cases of cancer to the California Cancer Registry pursuant to California law and regulations. See 45 CFR sec. 164.502(b)(2)(v).

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WHAT INFORMATION IS REQUIRED FOR A COVERED ENTITY TO MEET THE PRIVACY RULE'S VERIFICATION REQUIREMENTS WITH RESPECT TO REPORTING INFORMATION ABOUT CASES OF CANCER TO THE CALIFORNIA CANCER REGISTRY?

The Privacy Rule requires covered entities to verify a requester's identity before disclosing protected health information. See 45 CFR sec. 164.514(h)(1)(i). In the case of disclosure to a person acting on behalf of a public official, a covered entity that reasonably relies on a written statement on appropriate government letterhead that the requester is acting under the government's authority will fulfill this requirement. See 45 CFR sec. 164.514(h)(2)(ii)(C). The Privacy Rule also requires covered entities to verify the requester's authority. See 45 CFR sec. 164.514(h)(1)(i). A covered entity that reasonably relies on a written statement of the legal authority under which the information is requested will fulfill this requirement. See 45 CFR sec.
164.514(h)(2)(iii)(A). To assist covered entities in meeting the verification requirements, the California Department of Public Health has provided a written statement to cancer reporting facilities with the aforementioned information.

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ARE COVERED ENTITIES REQUIRED TO SIGN "BUSINESS ASSOCIATE AGREEMENTS" WITH REGIONAL REGISTRIES THAT PERFORM ON-SITE ABSTRACTING AND CANCER DATA REPORTING?

No. One way that the California Department of Public Health makes sure it obtains complete information about cancer cases is to give cancer reporting facilities that want to minimize their reporting burden the ability to contract with the regional registries for onsite abstracting and reporting. See 17 Cal. Code of Regulations, sec. 2593(b)(17).  HIPAA requires business associate agreements with entities that carry out health care functions on behalf of covered entities, but the regional registries are acting on behalf of the California Department of Public Health when they provide on-site abstracting and reporting services, not the covered entity. Therefore, they are not business associates.

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DOES HIPAA APPLY TO THE USE OR DISCLOSURE OF INFORMATION ABOUT CANCER CASES AFTER IT HAS BEEN REPORTED TO THE CALIFORNIA CANCER REGISTRY?

No. The Privacy Rule applies to disclosure of protected health information by covered entities as required by law. It does not apply to subsequent use or disclosure by the recipient. However, the California Cancer Registry authorizing legislation includes strict limits on use and disclosure of reported information. Those requirements include obtaining a federally designated Institutional Review Board approval, and contractual agreements to maintain confidentiality and privacy of the data and to not disclose confidential information beyond the confines of the specific research project. See Ca. Health & Safety Code sec. 103885(g). When a researcher contacts a patient, they are required to inform the patient of how they obtained the patient’s name, that the patient is under no obligation to participate in the study, that their participation or non-participation will not be reported to anyone, and that they may request that no one contact them again. Occasionally a patient will object to having their name released without prior consent, and CCR has methods to restrict those names from future contacts. But many patients are happy to participate in special studies in order that we all may learn more about cancer in order to make progress against this deadly disease. CCR was created to serve as a resource for research into the causes and cures of cancer, and it has a productive record of using CCR data for research. Furthermore, in over 50 years of CCR’s operation, we are not aware of any unwarranted release of confidential information from CCR or researchers.

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ARE COVERED ENTITIES REQUIRED TO PROVIDE INDIVIDUALS UPON REQUEST WITH AN ACCOUNTING OF ANY PROTECTED HEALTH INFORMATION THAT THE ENTITY HAS DISCLOSED ABOUT THEM TO THE CALIFORNIA CANCER REGISTRY?

Yes. The Privacy Rule requires covered entities to provide an accounting of disclosures of protected health information. See 45 CFR sec. 164.528.


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II. California Cancer Registry Data: FAQs

Subsection I: QUESTIONS RELATED TO DATA & STATISTICS AVAILABLE TO THE GENERAL PUBLIC

ABOUT DATA FROM THE CCR

The California Cancer Registry (CCR) provides aggregated cancer data for statistical purposes. Cancer statistics for California as a whole, for regions of the State, and for individual counties are available on our online Data and Mapping Tool. Questions that cannot be answered by our Data and Mapping Tool may be answered by contacting staff at the CCR.

Individuals also have the right to access records containing their personal information maintained by CCR according to CA Health and Safety Code Section 103885 (g)(10) and the California Information Practices Act, Civil Code Sections 1798 – 1798.78. Maintaining the confidentiality of persons whose cancers are reported to CCR is mandated by law and is the highest priority in registry operations. No data are intended to be used to identify individuals with cancer.

All of California participates in the Centers for Disease Control and Prevention’s (CDC) National Program of Cancer Registries (NPCR), and in the Surveillance, Epidemiology, and End Results (SEER) program of the National Cancer Institute. CCR data meets all NPCR and SEER standards for quality, timeliness and completeness.

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HOW CAN I ACCESS DATA ON THE CANCER RATES IN CALIFORNIA, IN MY COUNTY, AND/OR IN MY CITY?

Some data from the California Cancer Registry is available to the public and can be used for such purposes as research, program planning and grant applications.

The California Cancer Registry (CCR) has an online data and mapping tool that will allow you to generate customized maps and tables of California cancer incidence or mortality rates by sex, race/ethnicity and by county (for individual counties that have populations large enough to produce stable rates). Please go to www.ccrcal.org/Data_and_Statistics/index.shtml to access this data query system.

The California Cancer Registry (CCR) produces annual reports on statewide cancer incidence and mortality rates from1988 through the most recent year for which data are complete.  The reports are usually published in the spring of each year, and are available on request, and on our web site under “Reports and Factsheets.”

The estimated number of new cancer cases and deaths for the current year in California and in each county is in California Cancer Facts and Figures published each year by the American Cancer Society and the CCR. This publication is available on request to ACS (1-800- ACS-2345), and is also available on our web site.

The CCR does not produce cancer rates for cities, because population data for cities are not available in the age group, gender, and race/ethnicity categories required.

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WHO CAN I CONTACT IF I HAVE QUESTIONS ABOUT THE DATA AND MAPPING TOOL OR THE EXISTING CCR REPORTS?

Any questions can be emailed to webmaster@ccr.ca.gov

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HOW DO CANCER RATES IN CALIFORNIA COMPARE TO THE UNITED STATES AS A WHOLE?

Cancer rates for the United States are estimated by the Surveillance, Epidemiology, and End Results (SEER) Program.  The SEER Program registers cancer patients in geographic areas covering about 28% of the U.S. population, including all of California.

In 2005-2009, the overall cancer incidence rate in California was 9% lower than the nation excluding California.  California cancer incidence rates for Asian/Pacific Islanders, African Americans, and non-Hispanic whites were between two and three percent lower than the nation.  Hispanics in California had a nearly 5% lower incidence rate than other Hispanics in the nation.  Some of the differences in rates many reflect difference in classifying the race/ethnicity of cancer cases between California and SEER.

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ARE CANCER RATES IN CALIFORNIA GOING DOWN?

Overall, cancer incidence rates in California have declined by 11% from 1988 to 2009.  Over the same period, cancer mortality rates declined by 23%.  Mortality rates declined for all four major racial/ethnic groups in the state. Specifically, tobacco-related cancers continue to decline, including cancers of the lung and bronchus, larynx, oral cavity, pancreas, stomach, and bladder.  California has experienced a much larger decrease in lung cancer incidence rates than the United States in large part due to the success of the California tobacco control initiative.

However, even if the rates of cancer change very little, the number of people who develop cancer will increase as the population gets older. Combined with the fact that more people are surviving cancer and that people discuss cancer more readily, this may contribute to the widespread impression that the risk of developing cancer has increased recently.

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WHERE CAN I GET DATA ON CANCER RISK BEHAVIORS OR CANCER SCREENING RATES?

While the California Cancer Registry does not gather this type of data, there are several statewide surveys that do.  The California Behavioral Risk Factor Survey (BRFS) and the California Health Interview Survey (CHIS) are both excellent resources for this type of information.  California BRFS data and reports can be accessed at the following link: http://www.surveyresearchgroup.org/sub.php?page=data.  CHIS data can be accessed online at the following link: http://www.chis.ucla.edu/.

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Subsection II: QUESTIONS RELATED TO RESEARCHERS (DATA & APPLICATION)

CAN I REQUEST CCR DATA FILES FOR RESEARCH PURPOSES?

The California Cancer Registry is no longer able to provide a public use data file.  Confidential data required for research are provided only to bona fide researchers with research projects that meet stringent requirements for scientific merit and handling of confidential information.  The CCR provides data to researchers who meet the following criteria:

  • Must have approval from the state’s Committee for the Protection of Human Subjects (CPHS) Institutional Review Board (IRB)
  • Must have approval from your institution’s Institutional Review Board (IRB) 
  • Agree to the California Department of Public Health data disclosure policy

You can find instructions on how to obtain CCR data for research at: http://www.ccrcal.org/Data_and_Statistics/Cancer_Data_for_Research.shtml

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HOW COMPLETE ARE CALIFORNIA CANCER REGISTRY DATA?

Every cancer diagnosis made in California from 1988 onward is required by law to be reported to the California Cancer Registry (CCR). The exceptions are the common skin cancers (basal and squamous cell carcinomas) and certain non-invasive cancerous conditions of the uterine cervix. The CCR, as well as the regional registries, the cancer registrars, and others who collect cancer data for the CCR, all make a major effort to ensure that the data are as accurate and complete as possible. The level of completeness increases with time.

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WHY IS CALIFORNIA CANCER REGISTRY CANCER DATA ALMOST TWO YEARS BEHIND?


All cancer registries which publish high quality data have a substantial lag period before the data for a given year are complete. The California Cancer Registry (CCR) puts a high priority on reducing this lag period as much as possible without compromising data quality.

A number of circumstances are involved in the delay before a cancer case is reported to the CCR. Complete information on the case and on the first course of treatment may not be available until six months after the initial diagnosis. Many cases are reported to the regional registries by multiple facilities or health care providers, and all the reports must be consolidated into a single record containing the best information available. Another factor is the increasing number of cancer patients who are diagnosed and treated in doctors' offices without ever being admitted to a hospital; more effort is required to find these cases. In addition, the strict quality control procedures needed to produce complete and accurate data are labor intensive, and the CCR has limited resources. The vast majority of cases are reported to the CCR within 12 months of the diagnosis date, but the data are not released until case reporting is estimated to be at least 95 percent complete - and the last 10 percent are the hardest to complete.

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Does HIPAA require covered entities to obtain written authorization from the individual before reporting protected health information to the California Cancer Registry?

No. The provision of the Privacy Rule authorizing disclosure of protected health information as required by law is an exception to the requirement for written authorization. See 45 CFR sec. 164.512(a)(1).

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How Do I Request data for research?

There are three types of requests that can be made: case-listings for data analysis only, case-listings for patient contact, and data record linkages. All three requests are specific to an approved project.  For requirements and information for confidential data requests, see the CCR web site at http://www.ccrcal.org/Data_and_Statistics/Cancer_Data_for_Research.shtml or email the CCR at research@ccr.ca.gov.

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Is there a cost for requesting data for research?

Yes, there is a cost associated with these data requests.  To view pricing and cost information, see the CCR web site at: http://www.ccrcal.org/Data_and_Statistics/CCR_Pricing_Sheet.shtml.

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Do I need to submit a Confidentiality Agreement for Access to CCR Data(also referred to as Appendix 2)?

No, the Principal Investigator (PI) of the project will grant access to the individuals using the CCR data at your location. The PI will sign as the CCR data custodian and need to keep the signed Appendix 2s in their files. They may be asked to submit a list of individuals with access on an annual basis.

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How detailed does my justification need to be for my list of requested variables?

You can group your list of variables by topic (please include the specific variables’ names) and then give a brief 2-3 sentence justification.

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Are there discounts for students available?

Student discounts may be available if the following criteria have been met:

    • Must have both institutional and state IRB approval.
    • Agree to the CDPH data disclosure policy
    • Students must additionally have a faculty mentor, who will be ultimately responsible for research.

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What if we currently do not have funding?

There are other data resources that are of no cost to you.  For example, our web-based data support can provide you cases counts and age-adjusted incidence rates by county on a variety of cancers. Please go to:  http://www.ccrcal.org/Data_and_Statistics/index.shtml .

Cancer data is available from SEER for California | SEER website: http://seer.cancer.gov/data/

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III. Patient Information: FAQs

 

Subsection 1

WHAT DATA DOES THE CCR COLLECT AND WHAT ARE THE DATA USED FOR?

The CCR collects demographic, diagnostic, and treatment information on individual cancer cases directly from cancer patient’s medical records.  The CCR does not interview patients.

This data is used to:

  • Monitor the number of new cancer cases and cancer deaths over time.
  • Examine disparities in cancer risk, treatment, and survival.
  • Examine treatment choices and other predictors of survival.
  • Measure the success of cancer screening programs.
  • Respond to public concerns and questions about cancer.
  • Conduct research to find the causes and cures of cancer.

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WHAT HAPPENS TO THE DATA?

The CCR and regional registries use the data to write summary reports that inform the public, local health workers, educators, and legislators about the status of cancer.

These summary reports do NOT contain any information on individual cancer cases.  The data in these reports are combined into groups for analysis.

Researchers may examine these data to identify areas that have high cancer rates, and areas where people might benefit from cancer screening and education programs.

Researchers can also use these data to look at trends in cancer diagnoses.

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Subsection 2

ARE CANCER PATIENTS ASKED TO PARTICIPATE IN RESEARCH STUDIES?

Some studies require that researchers obtain additional information from individual cancer patients.

The CCR and regional registries are permitted to release patient contact information to qualified researchers.  These researchers may contact patients to find out if they want to participate in a research study.

The same state law that mandates that all cancers diagnosed in California be reported to the California Department of Public Health, which operates the CCR, also requires that cancer registry data only be released for research into the causes and cures for cancer. The law mandates that patient identity be kept confidential, but also that confidential information may be released for such research.

The physician and/or hospital where a cancer patient was diagnosed should have provided a pamphlet or other document for their review regarding the cancer reporting law and notifying them that researchers may contact them.

The CCR takes the protection of a patient’s confidential health information very seriously. 

The CCR will only release information to qualified researchers under tightly controlled circumstances where the research has first been approved by the California Committee for the Protection of Human Subjects (CPHS).

Patients have the right to refuse to participate in any research study without jeopardizing their current or future medical care.

Patient rights are monitored and protected by a federally approved Institutional Review Board (IRB) at the researcher’s institution.  Patients are encouraged to report any concerns or complaints to the IRB.  Information about how to contact the IRB should be included in the initial contact letter from the researcher.

Cancer patients may request that their contact information be withheld from researchers by contacting the CCR at the number at the bottom of this webpage.

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WHY PARTICIPATE IN CANCER RESEARCH?

  • It offers an opportunity to join the fight against cancer.
  • Thanks to the participation of many cancer patients, their families, and people without cancer, hundreds of research studies have been conducted using CCR data.
  • This research has contributed to the discovery of major risk factors for cancer, improved treatment, and better survival for cancer patients in California and across the United States.

Researchers have used the CCR data to:

  • Analyze geographic, racial/ethnic, and occupational differences in cancer risk;
  • Evaluate the quality of medical care received by cancer patients; and
  • Examine patient survival with respect to cancer type, extent of the disease, demographic characteristics, and other important factors.

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Subsection 3

HOW DO I GET A COPY OF MY CANCER REGISTRY FILE/INFORMATION

California Cancer Registry (CCR) records can only be released to those who are legally authorized to obtain a patient’s confidential information (i.e., self, surviving spouse, conservator, etc.)  The CCR requires all patient record requests be made in writing.  The application and check list are available on the CCR website:

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CAN YOU REMOVE MY NAME AND PERSONAL INFORMATION FROM THE CALIFORNIA CANCER REGISTRY?

The state mandates that all cancers diagnosed in California be reported to the California Department of Public Health for the California Cancer Registry (CCR).  The CCR does not provide for removal of cancer patient information from the registry. To fulfill its purpose of providing information to find the causes and cures for cancer, it is vital for the CCR records to be complete.

The law mandates that CCR data only be released for research into the causes and cures for cancer.   The law mandates that patient identity be kept confidential, but also that confidential information may be released for such research.

However, patients can refuse to participate in any particular research study or all research studies.  Cancer patients may request that their contact information be withheld from researchers by contacting the CCR at the number at the bottom of this webpage.

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Subsection 4

If you have any questions or concerns about these patient-related topics, please feel free to contact the CCR at 916-779-0300 or email us at webmaster@ccr.ca.gov.  

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IV. General Cancer Overview: FAQs

HOW COMMON IS CANCER?

In California, more than 140,000 people will be diagnosed this year with some form of cancer, not including the common skin cancers.  This is equivalent to more than 16 new cases every hour of every day. Despite the fact that cancer incidence and mortality rates are declining, it is estimated that nearly one out of every two Californians born today will develop cancer at some point in their lives, and it is likely that one in five will die of the disease.

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WHICH TYPES OF CANCER ARE MOST COMMON?

There are many different kinds of cancer depending on where in the body the cancer starts and the type of cell involved. The most common types for males are prostate, lung, colorectal, urinary bladder and melanoma cancers. The most common types for females are breast, lung, colorectal, uterus and thyroid cancers. 

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WHO GETS CANCER?

Unfortunately, cancer can strike at any age, even among children and young adults. However, over 50 percent of the cancers diagnosed in California are among people 65 and older, who make up only about 11 percent of the population. Surprisingly, there are large differences among people of different ethnic origin. African-American men have the highest cancer risk, and non-Hispanic whites have substantially higher cancer rates than persons of Latino or Asian origin. Children have few differences in their cancer rates regardless of their ethnic origin.  Many cancers can be cured if detected and treated promptly, and many others can be prevented by lifestyle changes, including avoidance of tobacco, consuming a healthy diet and being physically active.

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HOW MANY PEOPLE CURRENTLY HAVE CANCER?

The current estimate in the recent California Cancer Facts and Figures is that more than 1,277,200 Californians who are alive today have a history of cancer, not including basal or squamous cell carcinomas of the skin or certain non- invasive cancerous conditions of the uterine cervix. Many of these individuals have no further evidence of the disease, and have the same life expectancy as people who have never been diagnosed with cancer.

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HOW CAN I FIND OUT MORE ABOUT A PARTICULAR CANCER?

The National Cancer Institute's Cancer Information Service at 1-800-4-CANCER ( 1-800-422-6237), and voluntary organizations such as the American Cancer Society (1-800-ACS-2345) (or the ACS office in your area) provide information on cancers. The Centers for Disease Control and Prevention is also an excellent resource for information on cancer (http://www.cdc.gov/cancer/). 

The California Department of Public Health has a number of programs that focus on cancer prevention, control, screening and/or treatment including the California Obesity Prevention Program, The Network for a Healthy California, the California Tobacco Control Program, Every Woman Counts Program (breast and cervical cancer screening and diagnostic services), the Prostate Cancer Treatment Program, the California Colon Cancer Control Program, and the Comprehensive Cancer Control Program (www.cdph.ca.gov). 

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HOW DOES CANCER COMPARE TO OTHER CAUSES OF DEATH IN CALIFORNIA SUCH AS HEART DISEASE?

Cancer is the second leading cause of death in California and the United States. In 2009, 24 percent of all California deaths were due to cancer, compared to 25 percent due to heart disease, the leading cause of death, and 6 percent due to stroke, the third leading cause of death. However, cancer has surpassed heart disease as the leading cause of death for Americans under the age of 85.

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HOW CAN I ENROLL IN A CLINICAL TRIAL FOR CANCER PREVENTION OR TREATMENT?

Information on clinical trials is available from the National Cancer Institute's Cancer Information Service at 1-800-4-CANCER (1-800-422-6237), and from their web site: http://www.cancer.gov/clinicaltrials.

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Community Cancer Concerns: FAQs

SEVERAL PEOPLE IN MY NEIGHBORHOOD HAVE BEEN DIAGNOSED WITH CANCER.  IS THIS UNUSUAL?

No, this situation occurs more often than you might expect. People often wonder if there are "too many cancers" in their neighborhoods, but most of the time it turns out that the number is about what we would predict. Here are some reasons why there may be quite a few people living in your neighborhood that have been diagnosed with a cancer:

  1. Cancers are very common. In California, about 51% of all men and 45% of all women will develop a cancer sometime during their lives*. Therefore, you will find people who have been diagnosed with a cancer in just about every neighborhood in the state. Cancers are most common in neighborhoods with lots of older residents because cancer risk increases with age.
  2. All cancers are not the same. There are many types of cancers. While all cancers involve out-of-control growth of cells, each type of cancer has different risk factors, causes, treatments and outcomes. So for example, if your neighborhood has three people with three different cancers (such as lung cancer, breast cancer, and liver cancer), those three people actually have three very different and distinct conditions - even though they all are called "cancer". These three types of cancer have very different causes, so there would be no reason to think that one common factor in the neighborhood would be to blame.
  3. Cancer rates often vary from year to year and from place to place by chance. The number of cancer cases will never be exactly the same in each neighborhood. In some places the number will be higher than average and some places it will be lower than average for no reason other than chance. Your neighborhood could just happen to have a higher than average number of people with new cancers just by chance.
  4.  People diagnosed with cancer are living longer. Currently, over half of all persons diagnosed with a cancer will be alive for five years or more after their diagnosis. Therefore, the chances are better than ever that there are a number of cancer survivors living in your neighborhood.

* Reference: California Cancer Registry, Annual Statistical Tables by Site (1988-2009)

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WHAT IS A TRUE CANCER "CLUSTER"?

A true cancer "cluster" is a situation in which there are more cancer cases in a group of people, in a location, or in a time period than would be expected based upon usual patterns. A true cancer "cluster" usually refers to a statistically significant excess of one particular type of cancer. A grouping of several different types of cancers is not usually considered to be a "cluster".

Public health officials and researchers who respond to questions about clusters from the public (also referred to as community cancer concerns) think of "clusters" in two distinct ways. The first is a suspected cluster (a concern has been reported but not yet evaluated). The second is a confirmed or true cluster (where officials have confirmed that the number of cases is in fact higher than expected). Public health officials nationwide receive hundreds of inquiries every year about suspected clusters. However, after an evaluation, only a small fraction of these suspected clusters are actually confirmed as true cancer “clusters”

Many people assume that if a “cluster” is statistically confirmed it means there is something wrong with the neighborhood environment (such as pollution of the air, water or soil). This is not necessarily the case. Usually the reasons cancers "cluster" in residential neighborhoods have little to do with the physical environment. In most cases, cancers "cluster" in neighborhoods because residents have similar cancer risk factors (such as smoking or being older), or by chance.

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WHAT ARE SOME COMMON MISCONCEPTIONS ABOUT TRUE CANCER CLUSTERS?

1: Most cancers and cancer "clusters" in residential neighborhoods are caused by environmental contamination.
False: The majority of known cancer risk factors are related to individual characteristics (such as age, race/ethnicity or genetic susceptibility) and behaviors (such as smoking, diet, physical inactivity, unsafe sex, and sun exposure). The relationship between cancers and environmental contamination in neighborhoods is much less established than most people realize. Nearly every investigation of a residential cancer "cluster" has failed to find a definite environmental cause.
2: A confirmed statistical excess of cancer cases in a neighborhood proves there is contamination.
False: Statistics can only tell us whether or not the cancer rate in your neighborhood is truly unusual compared to other times and places. They cannot tell us the reason why rates are unusual. Other information about your neighborhood and its residents would be needed to make sense of the situation. Even unusual rates often turn out to be due to coincidence.
3: Neighborhood cancer concerns are investigated by testing the air, water and soil for any synthetic chemicals.
False: Cancer concerns are investigated by determining whether or not there is actually an excess of cancer cases. In most cases, it turns out that there is not. If a statistically significant excess is found, the state and/or local health departments review the situation to determine if any further action is needed.
4: Causes of cancers are well understood by scientists and doctors.
False: Although scientists have learned a great deal about the complex nature of cancers, much remains unknown. In populations, we know every year about how many cases of cancers we can expect, and can predict that cancer rates will be higher or lower in different groups of people. In individuals, however, no one can say for certain what exactly caused a cancer to develop.

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WHY ARE CANCER RATES HIGHER IN SOME AREAS THAN OTHERS?

Whether a community cancer concern turns out to be a true cancer “cluster” or not, there are three general reasons why cancer rates may be higher in one area than another:

  1. Common risk factors: If a place has many older residents, for example, cancer rates will be higher than in a place with many younger residents. Some kinds of cancers are more common among people of one race or ethnicity than another. For example, breast cancer rates are generally higher among white women than among women of other races. Therefore, we would expect breast cancer rates to be higher in areas where the population is mostly white.
  2. Coincidence: Cancer rates may be higher or lower in an area compared to the rest of the state just by chance.
  3. The environment: Cancer rates could be higher in one area than another because of something in the physical environment. However, most scientists believe that environmental factors play a much smaller role than life- style related factors (such as smoking and diet) or personal risk factors (such as age, family history or race) in the development of most cancers.

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WHAT DOES IT MEAN WHEN THERE IS A "STATISTICALLY SIGNIFICANT" ELEVATION OF CANCERS IN AN AREA?

This means that researchers believe that the number of cancer cases in a place or time is greater than would be expected due to normal fluctuations alone and thus would be referred to as a true cancer “cluster.” Researchers use statistics to help them decide if a cancer rate is really unusual. For cancer concerns, researchers commonly agree that an excess of cancer cases is "statistically significant" when it is so different from average that you would expect it only 1 out of 100 times by chance alone.

The term "statistical significance" is tricky for many people to understand. "Statistical significance" only means that the number of cases that has occurred is unusual. It does not explain why the number of cases is high. Furthermore, it does not rule out chance as a cause.

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HOW DO INDIVIDUAL CHARACTERISTICS AND BEHAVIORS AFFECT CANCER RATES IN MY NEIGHBORHOOD?

By choice or by circumstance, people tend to live in neighborhoods where they have things in common with other residents, such as race or ethnicity, education, income, occupation or lifestyle. These types of characteristics are important elements of cancer risk. Some examples include:

Cancer risk increases with age. Therefore, we would expect to find higher cancer rates in areas with lots of older residents.

Prostate cancer rates are higher among African-American men than among men of other races or ethnicities. Therefore, we would expect to find higher prostate cancer rates in a largely African-American neighborhood than in a largely Hispanic or Asian neighborhood.

Breast cancer rates are higher among white women than among women of other races. They also tend to be higher among women with higher socioeconomic status. Therefore, we would expect to find higher breast cancer rates in communities with many affluent white women than in other communities with a different racial and socioeconomic mix. (One reason for this difference is that women of higher socioeconomic levels more often delay child bearing and have fewer children, which in turn increases breast cancer risk.)

Residents of some communities may have similar lifestyle habits that increase risk, such as smoking, lack of physical activity or unhealthy diet. Therefore, we would expect to find higher rates of smoking-related cancers (such as lung cancers) in neighborhoods where a high proportion of residents are smokers than in neighborhoods with few smokers.

When researchers try to explain differences in cancer rates between neighborhoods, they take age, sex, and race into account.

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HOW CAN SO MANY CANCER CASES IN MY NEIGHBORHOOD BE DUE TO CHANCE?

Chance is an explanation for true cancer "clusters" more often than most people realize. Most people accept the laws of chance when it comes to games like the state lottery. It's harder for most people to accept that these same laws of chance can apply to a serious disease like cancer.

A single neighborhood has a low probability of having high cancer rates just due to bad luck (in other words, chance). However, if you look at the entire state, you would see that lots and lots of people get cancers and there are lots and lots of neighborhoods. Therefore, there is a very good probability that some neighborhoods will have this kind of bad luck. If it happens to be your neighborhood, you naturally want to know why this has happened. Most people understandably find that "bad luck" is not a very satisfying explanation and want something --or someone --to be held responsible.

Nonetheless, most experts on cancers and cancer "clusters" believe that chance is the explanation for neighborhood cancer "clusters" far more often than most people would think. "Chance" in this situation means that there is no common reason why cancers have occurred in a particular neighborhood. Given the same set of genetic and lifestyle factors, the same people probably would have gotten cancer no matter where they lived. But sometimes several people who develop cancer just happen to live in the same area -- by chance. An investigation into the cause of a chance "cluster" will never result in an answer because none exists.

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DOES THE ENVIRONMENT CAUSE CANCER?

Yes it can, but it plays less of a role than many people believe.

One reason for confusion about this is that the term "environment" means something different to researchers than it does to most members of the public. For researchers, the "environment" usually means any factor that is not hereditary. This may include things like cigarette smoking, diet, sunlight and infections in addition to factors in the air, soil and water. If we use this broad definition, we would say that the "environment" is a big factor in cancer risk.

However, when most members of the public think of cancer and the "environment" they are thinking of contaminants in the air, water, or soil that might cause cancers (called carcinogens). We all live in environments that contain carcinogens, and we are all exposed to a greater or lesser degree every day. The relationship between these carcinogens and cancer development is subtler, more complex and less established than most people think.

Much of what we know about these carcinogens has been learned from studies of exposures in the workplace. In the workplace, unlike in neighborhoods, chemical exposures are more often known, and occur at high levels for prolonged periods of time.

Learning more about environmental carcinogens and their role in cancer development is very important. Because their effects are complex and difficult to detect, studies of environmental carcinogens and cancer must be carefully designed and include large numbers of people. A neighborhood with a cancer "cluster" is not a very good place to study the effects of environmental carcinogens because usually the number of cases is too small, and the number of possible carcinogens is too large to be able to make a connection.

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WHY HAVE INVESTIGATIONS OF TRUE CANCER CLUSTERS NOT BEEN USEFUL IN IDENTIFYING ENVIRONMENTAL CAUSES OF CANCERS?

Over the years, nearly every neighborhood cancer "cluster" investigation has failed to identify any environmental cause. This is not for lack of trying, but because cancers are very complex diseases. Methods that work well to identify the cause of an infectious disease outbreak do not work well with neighborhood cancer clusters. The reasons include:

  1. Cancers take a long time to develop. For most cancers, the period between exposure to a carcinogen and the development of cancer may be ten to twenty years or more. By the time cancer rates have increased in an area, the carcinogen may no longer be measurable in the environment.
  2. People change residences. In many cases, by the time a person is diagnosed with a cancer, he or she no longer lives in the area where an exposure may have occurred. Cancer registries have no way to track where people lived before or after developing a cancer.
  3. Residential cancer clusters contain few cases. Even if the cancer rate in an area is found to be "statistically significant" there usually are too few cases and too many possible exposures to allow scientists to work backward to find the cause. Carcinogens that may be found in a neighborhood with several cancer cases are also likely to be found in areas without many cases.
  4. It is not currently possible to determine the cause of cancer in an individual. When a person gets a cancer, doctors may suspect that certain risk factors are largely to blame. However, doctors do not have any reliable way to determine the exact cause or combination of causes for the cancer. Therefore, in a neighborhood "cluster" situation, doctors cannot be certain about what caused a cancer in any individual resident.

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IF THERE ARE A LOT OF PETS IN MY NEIGHBORHOOD WITH CANCER DOES IT MEAN THERE IS A PROBLEM WITH THE ENVIRONMENT?

The state does not track cancers in animals. Therefore, there really is no way to tell if the number of animal cancers in any particular neighborhood is truly unusual. However, we know that cancers are common especially among older animals. This is because cancer risk increases with age, just as it does in people.

Humans and animals have different cancer risks. Cancers that are uncommon in humans may be very common among dogs, for example, and vice-versa. Cancer risks also vary between different animals, and even within breeds of the same species. There is no reason to suspect that groupings of different types of animals with different types of cancers have a common underlying cause.

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Subsection 2

WHO SHOULD I CONTACT WITH MY QUESTIONS OR CONCERNS ABOUT CANCERS IN MY COMMUNITY?

You may call either your county or local health department or the regional registry that covers the county in which the community is located.

In most counties, the county health department should be contacted first. These departments will usually be familiar with local issues, and you may find that officials are already aware of the area you are concerned about. County health departments may respond to community cancer concerns themselves or refer callers to the regional registry depending upon the resources available in each county.

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Subsection 3

HOW ARE CANCER CONCERNS INVESTIGATED?

The first step is to determine whether or not you are asking about a pattern of cancers that is really unusual. People often report cancer concerns that include lots of different types of cancers, or sometimes diseases that aren't actually cancers at all. In most cases, the epidemiologist is able to address the questions of the caller by providing current information about cancers, and to explain why the concern may not represent a real cancer excess.

Sometimes, further evaluation is necessary. The epidemiologist first works to identify the number of all observed cases of the cancer in the area and time period of concern. Then this observed number is compared to the number that would be expected based upon rates in other areas or other time periods, after adjusting for differences in the age, sex and race/ethnicity make-up of the populations. A statistical test is used to judge whether or not the difference between the number of cases observed and the number expected is likely to be due to normal random variation. If an excess number of cancer cases is confirmed, the situation is reviewed further by the health department to determine if any further investigation is needed.

Although this brief description may make this procedure sound simple, in fact it may require a considerable amount of registry staff time and resources, and may take several weeks to complete.

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RESOURCES FOR THE PUBLIC

County Health Department/Regional Registry Contacts:

California:

National:

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Other Questions?

If you would like any additional information regarding the California Cancer Registry please contact the Webmaster at webmaster@ccr.ca.gov or call the California Cancer Registry in Sacramento at (916) 731-2500.