Is it normal to have no blood marker for MCC cancer diagnosis?

Your oncologist is correct that MCC typically doesn't have reliable blood markers for monitoring, making PET scans a standard and effective way to track treatment response. Many cancer types rely on imaging rather than blood tests for monitoring, so this approach aligns with current medical practice for MCC. It's encouraging that you're receiving immunotherapy, which has shown promising results for this cancer type, and your medical team seems to be following established protocols for tracking your progress.

Getting ct scan on 4 mar 2026. Blood test

My brother was diagnosed Dec5 with MCC; saw cancer surgeon Jan. 26; first immunotherapy Feb 17. No shrinkage of tumor yet. Next infusion is March 19. Surgery is scheduled March 24. Praying for shrinkage and successful surgery. Everything just takes so long to get done.

The time between treatment and tests does seem so long. Our oncologist schedules PET scans after three immunology infusions; about every 10 weeks. It appears the immunotherapy is working, no evidence of MCC at last PET scan! Should mention that there were 33 radiation treatments before immunotherapy began.