Prolonged survival in adenocarcinoma of unknown primary treated with chemoradiotherapy

Cancer of unknown primary (CUP) represents 3% to 5% of all cancer malignancies in the world.1 Since 2003, CUP has been divided into 2 subsets – favorable (20% of the cases) and unfavorable (80% of the cases) – based on histopathologic and clinical manifestations.2 The impact of locoregional therapies, such as surgery and radiation, in addition to systemic chemotherapy in adenocarcinomas of unknown primary is not well described in the literature. We report here the case of a patient with adenocarcinoma of unknown primary with lymph-node–only metastases who has remained free of tumor progression for 2 years since completion of systemic multiagent chemotherapy followed by consolidation chemoradiotherapy (CRT).