XXXX of unknown primary site.

@entity5 @entity1 @entity900 @entity420
BACKGROUND: @entity5 of unknown primary site occupies 0.5-10% of all diagnosed @entity5 @entity1 and includes @entity5 with diverse responses to systemic chemotherapy. @entity420 of unknown primary site (ACUPS), the most common subtype, has no standard treatment, rarely responds to conventional treatment and has a poor survival rate. METHODS: The retrospective study was performed to investigate the clinical characteristics and the treatment outcomes of ACUPS. RESULTS: Eighty-one @entity1 with ACUPS diagnosed at Samsung Medical Center from May 1995 to July 1999 were included. The median age was 58 years (range, 29-77). The common sites of metastases were the lymph node, liver, lung and bone in order. In 49 of 81 @entity1 (60.5%), the dominant @entity5 location was below the diaphragm. The majority of @entity1 (76 of 81) were initially treated with systemic chemotherapy including @entity900 . Responses were evaluable in 70 of 76. Eighteen of 70 @entity1 (25.7%) responded to chemotherapy and complete remission was observed in 6 @entity1 . The overall median survival of 81 @entity1 was 5.6 months. The median survival of the responding @entity1 was 18.3 months but the median survival of the nonresponding @entity1 was 4.6 months (p < 0.01). In univariate and multivariate analysis, age, performance status and response to initial chemotherapy were significant prognostic factors for overall survival. CONCLUSION: We observed poor response to the treatment and survival rate in ACUPS, but complete remission and long-term survival were observed in a small number of @entity1 .
