How Is Carcinoma of Unknown Primary Classified?
If your doctor still cannot find the primary site of the cancer after doing a number of different tests, you may be officially diagnosed with carcinoma of unknown primary origin (CUP). A pathologist will review the biopsy samples and classify the cancer as one of these five types:
The pathologist's classification of the cells from the biopsy will help your doctor to determine a treatment plan, even if the original site of the cancer remains unknown.
You may need some of these additional exams:
Doctors will repeat a careful physical exam and maybe some of the prior tests. They will have a second pathologist look at the biopsy samples. Sometimes, as time passes, a small hidden primary tumor may become large enough to be found. This may help the doctors reclassify the CUP.