What is the prognosis for adenocarcinoma of an unknown primary?

The prognosis for adenocarcinoma of an unknown primary (CUP) is generally poor, with a 5-year survival rate of around 5-10%. This is because CUP is often diagnosed at an advanced stage, when the cancer has already spread to other parts of the body. The prognosis for CUP can vary depending on the specific type of adenocarcinoma and the stage of the disease at diagnosis. Some types of adenocarcinoma are more aggressive than others, and the earlier the disease is diagnosed and treated, the better the prognosis.