California Cancer Reporting System Standards Volume I: Abstracting and Coding Procedures for Hospitals
Enter the code for neoplasm (8000) for unspecific terms such as "malignant tumor," "malignant neoplasm", and "cancer". Do not use the code for a clinically malignant tumor that has not been microscopically confirmed (9990).
Use code 8001 (malignant cells, NOS), if a diagnosis is based only on a cytology report stating "malignant cells".
See also Section IV.2.