June 19, 2023
Tumor Tip of the Week- 06-16-2023 Prostate cM1a cM1b or cM1c
06-16-2023 Prostate cM1a cM1b or cM1c
Scenario 2023:
Patient diagnosed with Prostate Adenocarcinoma was found to have mets to distant lymph nodes and bones on Scans.
Question: How would you assign the cM category?
- M1a Nonregional lymph node(s)
- M1b Bone(s)
- M1c Other site(s) with or without bone disease
Answer: M1b Bone(s)
Rationale:
AJCC Cancer Staging Manual, Eighth Edition Chapter 58 Prostate
In my opinion, I personally found the instructions and note in the AJCC Cancer Staging Manual a little bit confusing, so I consulted the CAnswer forum for an explanation to help me understand whether to code a cM1b or cM1c.
After researching, this is the rationale behind the choice. The patient had distant lymph node mets which would be a cM1a, then they also had distant bone mets so that would be a cM1b. So, that is the most advanced category used, we would stop there and assign a cM1b. The category cM1c would be used for mets to sites other than non-regional nodes or bones, like lung or liver.
CAnswer Forum post
