Carcinoma of Unknown Primary When cancer is found in one or more metastatic sites but the primary site is not known, it is called a cancer of unknown primary (CUP) or an occult primary cancer. find my drugs cancer All About Cancer of Unknown Primary Cancer of unknown primary (CUP) is a metastatic cancer that has been diagnosed by a biopsy but the primary location, or the place where the cancer started, cannot be identified. Support
All About Cancer of Unknown Primary Cancer of unknown primary (CUP) is a metastatic cancer that has been diagnosed by a biopsy but the primary location, or the place where the cancer started, cannot be identified.