Management of patients with cancer of unknown primary site

Cancer of unknown primary site represents approximately 3% to 5% of all new cancer diagnoses. Adenocarcinomas account for 60% of all unknown primary cancers and poorly, differentiated carcinomas or adenocarcinomas, for 30%, Historically, the prognosis for most patients with unknown primary tumors has been poor, with survival often less than 6 months from diagnosis. Recent advances in diagnostic techniques, including immunocytochemical and molecular genetic methods, have increased the probability of identifying a likely underlying tumor type. Based on clinical and pathologic features, approximately, 40% of patients can be categorized within subsets for which specific treatment has been defined. Empiric therapy is an option for the remaining 60% of patients, In these patients,favorable prognostic factors for treatment response include tumor location in lymph nodes,fewer sites of metastases, younger age, and poorly differentiated carcinoma histology, Although experience remains limited, the incorporation of a taxane into empiric regimens appears to improve response rates and survival A recent study of paclitaxel (Taxol), carboplatin (Paraplatin), and etoposide in 55 patients with cancer of unknown primary site reported an overall response rate of 47% and a median overall survival of 13.4 months. Investigations continue to explore new diagnostic techniques and novel therapeutic approaches.