California Cancer Reporting System Standards Volume I: Abstracting and Coding Procedures for Hospitals
Certain types of neoplasms arise only or usually in certain organs, such as hepatoma (the liver), nephroblastoma (the kidney), retinoblastoma (the retina).
If the diagnosis in the medical record refers only to the histologic type, look it up in the ICD-O-3 index. In instances of site-specific morphology, the index refers to a topographic code. Enter that code if no site is specified in the diagnosis, or if only the metastatic site is given.
The code C22.0 (liver) is given after listings in the ICD-O-3 index for hepatoma, NOS; hepatoma, benign; hepatoma, embryonal; and hepatoma, malignant.
If the site designated by a physician is different from the site referred to in the ICD-O-3 index, report the site specified by the physician.