Cancer of unknown primary site

Although the term cancer of unknown primary site (CUPS) is sometimes used interchangeably with carcinoma (cancers of epithelial differentiation) of unknown primary site, not all cancers of unknown primary site are epithelial in origin. This chapter will review the triage and evaluation of all types of cancers, but the main focus will remain on the carcinomas, which form the predominant category (—90% to 95% cases) of CUPS. " ... 

Yakushiji S, Ando M, Yonemori K, et al. Cancer of unknown primary site review of consecutive cases at the National Cancer Center Hospital of Japan. Int J Clin Oncol. 2006 11 421-425. 

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