Home > Part V. Tumor Data > V.3 ICD-O Morphology - Histology, Behavior, and Differentiation
California Cancer Reporting System Standards Volume I: Abstracting and Coding Procedures
The morphology code indicates the type of cell that has become neoplastic (histology), its biologic activity (behavior), and the tumor grade or differentiation.
CCR NOTES:
The implementation of the new ICD-O-3 histology codes will not be implemented until 2018. Please continue to use the Histology Code Crosswalk for 2017.
2015 ICD-O-3 histology coding changes: There were histology coding changes being implemented for 2015. Many of the new codes could not be used for 2015 diagnoses because they were not included among the acceptable histologies for the Collaborative Stage algorithms. For the New ICD-O-3 Histology Code Crosswalk for 2015 through 2017, please see Volume I - Attachment A.
The morphology code consists of three parts:
The histology code (first four digits)
The behavior cord (the fifth digit)
And the grade of differentiation code (the sixth digit)
Histology code identifies the specific cell type of the tumor. Specific cell lines come from different tissues and are extremely important information for the diagnosis and treatment of the disease. For cases or tumors diagnosed after January 1, 2007, also refer to the 2007 Multiple Primary and Histology Coding Rules Manual to determine histology.
Examples:
Adenocarcinoma: is typically a cancer that begins in glandular (secretory) cells. Glandular cells are found in tissue that lines certain internal organs and makes and releases substances in the body, such as mucus, digestive juices, or other fluids. Most cancers of the breast, pancreas, lung, prostate, and colon are adenocarcinomas.
Squamous cell carcinoma: Cancer that begins in squamous cells. Squamous cells are thin, flat cells that look like fish scales, and are found in the tissue that forms the surface of the skin, the lining of the hollow organs of the body, and the lining of the respiratory and digestive tracts. Most cancers of the anus, cervix, head and neck, and vagina are squamous cell carcinomas. Also called epidermoid carcinoma.
Melanoma: A form of cancer that begins in melanocytes (cells that make the pigment melanin). It may begin in a mole (skin melanoma), but can also begin in other pigmented tissues, such as in the eye or in the intestines.
Sources for Determining Histology:
For solid tumors diagnosed January 1, 2007 forward, also refer to the 2007 Multiple Primary and Histology Coding Rules Manual to determine histology.
For hematopoietic and lymphoid cases diagnosed January 1, 2010 and forward, please refer to the 2010 Hematopoietic and Lymphoid Neoplasm Case Reportability and Coding Manual and the Hematopoietic Database.
Behavior code indicates whether a tumor is malignant or benign, or uncertain whether benign or malignant.
Grade is a measurement of how closely the tumor cells resemble the parent tissue (organ of origin). For Hematopoietic and Lymphoid Neoplasms, Codes 5, 6, 7, and 8 describe the lineage or phenotype of the cell. Code 9 indicates the cell type was not determined, not stated or not applicable.
The CCR has adopted the ICD-O-3 (International Classification of Diseases for Oncology, Third Edition) as its official morphology code system for all cases diagnosed January 1, 2001 forward.
Note: Although ICD-O-3 is referenced in coding site and histology throughout this document, unless otherwise noted, these statements also apply to ICD-O-2 coding.
Enter the appropriate morphology code