Authors' recommendations: Cancer of unknown primary (CUP) is the presence of a metastatic tumor for which the primary carcinoma cannot be identified. There is no single definition of what examinations and tests are needed before a diagnosis of CUP is appropriate. The definition of CUP used by the National Cancer Institute (NCI) is a metastatic tumor for which the primary has not been identified following a biopsy of the tumor; complete physical examinations of the head and neck, rectal, pelvic, and breast regions; chest x-rays; a complete blood count; urinalysis; and analysis for occult blood in the stool. In the United States, 30,000 to 80,000 new diagnoses of CUP are estimated to be made every year, and the median age of diagnosis of CUP is 60 years. CUP occurs equally in both men and women, although the prognosis for men is generally worse than for women. The prognosis of patients with CUP is generally poor, with the median survival after diagnosis only 3 to 4 months even with treatment. Approximately 25% of patients will have the primary cancer site identified between diagnosis and death. Autopsy studies lead to identification of the primary site in 50% to 75% of patients who have succumbed to CUP, but a primary tumor is never identified in 20% to 50% of patients. Immunohistochemistry (IHC) analysis of CUP tumors is often used to histologically characterize the tumors and, if possible, define the cell type. However, IHC analysis has not been shown to improve health outcomes of patients with CUP. Treatment of CUP is often empiric; although some types of CUP may respond to specific treatment regimens, there is little evidence of the clinical benefit of these specific regimens. Treatment regimens for cancer are often specific to the cell type of the primary tumor. Consequently, it has been hypothesized, but not yet proven, that identification of the cell type of the primary tumor in patients with CUP may lead to improved patient outcomes through the use of treatments targeted to the primary tissue type. Several gene expression tests have been designed to identify the primary tumor cell type by analysis of RNA to derive the expression of genes in the CUP tumor.

Project Status: Completed

Year Published: 2012

URL for published report: The report may be purchased from:http://www.hayesinc.com/hayes/crd/?crd=14362

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: United States

Organisation Name: HAYES, Inc.

Contact Address: 157 S. Broad Street, Suite 200, Lansdale, PA 19446, USA. Tel: 215 855 0615; Fax: 215 855 5218

Contact Name: saleinfo@hayesinc.com

Contact Email: saleinfo@hayesinc.com

Copyright: 2012 Winifred S. Hayes, Inc