Cancer of unknown primary. A retrospective study based on 109 patients.

Cases of 109 patients with metastases from cancer of unknown primary (CUP) were retrospectively analyzed. The highest survival rates were observed in patients with high performance status and metastases limited to the cervical lymph nodes. With other metastatic presentations, the survival was generally very short. Tumor markers did not demonstrate diagnostic value. The primary tumor was revealed by autopsy in 43 of 64 cases. Lungs were the most common primary site, followed by the gastrointestinal tract. Extensive clinical investigations during the initial diagnostic period were, as a rule, fruitless. Patients with CUP require efficacious treatment, but need to be investigated with adequate measures.