California Cancer Reporting System Standards Volume I: Abstracting and Coding Procedures
A primary neoplasm is the original lesion, as compared to a tumor that has developed as a result of metastasis or extension. A patient might have many lesions that developed from one tumor or different tumors that developed independently.
Refer to the most current Multiple Primary and Histology Coding Rules for coding instructions. This applies to cases diagnosed January 1, 2007 and forward. The following MPH rules:
Replace all previous multiple primary rules except those for hematopoietic neoplasms.
Determine the number of primaries to be abstracted.
Code the primary site to the location of the transplanted organ when a malignancy arises in a transplanted organ. See Terms and Definitions for types of transplants.
Do not use the Multiple Primary and Histology (MPH) Rules to determine reportability, stage or to assign grade.
For hematopoietic and lymphoid cases diagnosed January 1, 2012 and forward, use the 2012 Hematopoietic database and manual to abstract hematopoietic cases.
Kaposi's sarcoma (9140/3) is to be reported only once.