Q&A: TNM and SEER Summary Staging


Marketing Manager

Q: What is the SEER Summary stage for a patient diagnosed with metastatic disease to the bone and brain but a primary site is not identified (C80.9) – Unknown Primary Site.

A: Code 9 – Unknown. Per the Seer Summary Stage manual, page 281, the stage would be unknown as the primary site is unknown/not stated therefore the summary stage cannot be determined.


Q: In the AJCC 7th Edition, can you code a pathologic (pM0) if you have a negative biopsy of a suspected metastatic site?

A: No, Pathologic (pM0) is NOT a valid category and may not be assigned. Stage as cM0 per AJCC 7th edition page 11 under M classification rules.


Q: What is the clinical and pathologic stage grouping for carcinoma insitu of the breast?

A: Clinical and Pathologic Stage 0. Per AJCC 7th edition page 12 carcinoma insitu, stage pTis, cN0, cM0 as both clinical and pathologic stage 0.