Identifying the Primary Site in Metastatic Cancer of Unknown Origin

Abstract

Two hundred sixty-six patients with metastatic nonsquamous carcinoma of unknown origin underwent upper and lower gastrointestinal series, intravenous pyelograms, and chest roentgenograms (CR) for location of a primary cancer site. Of 129 identified primary cancer sites, only 22 were verified antemortem, whereas necropsy disclosed 25 cases with falsepositive examination results. The CR patterns thought typical for lung cancer (eg, single mass lesion and hilar or mediastinal adenopathy) were often shown (43%) to represent metastatic lesions. Because contrast roentgenographic studies are costly, uncomfortable, of low yield, and often misleading, they should be limited to cases with specific organ dysfunction. (JAMA241:381-383, 1979)