Disseminated Carcinoma of Unknown Primary Site: Detection with F-Fluorodeoxyglucose-Positron Emission Tomography

Abstract

Carcinomas of unknown primary site (CUP) are defined by the development of an epithelial metastatic disease (epidermoid carcinomas, well or poorly differentiated adenocarcinomas, poorly differentiated or undifferentiated carcinomas) in cases where the clinical, biological, and radiological examinations fail to identify the origin at the time of the therapeutic decision (Abbruzzese et al. 1994, 1995). In a general medical oncology service, metastatic carcinomas from an unknown primary site (CUP) constitute as many as 3-5% of referred patients with solid tumors (Seve 2008; Pavlidis et al. 2003). However, this incidence varies depending on the definition of CUP, the extent of the investigations that are performed, and the details of the patient population (Seve 2008). CUPs represent clinical problems that necessitate significant interactions between pathologists, oncologists, and primary physicians. The prognosis for these forms of cancer is regarded as very poor, with <10% of survival at 5 years (Abbruzzese et al. 1994).