Metastatic malignant disease of unknown origin

The charts of 106 patients with metastasis from an unknown primary cancer were reviewed to formulate a more appropriate investigative strategy than is presently employed. The spinal column was the most common site for initial presentation of metastasic disease (26.5 percent). The primary tumor was identified before death in 31.3 percent of patients and after death in 6.6 percent. Lung cancer was found in 40 percent of patients with identified primary tumors. Diagnostic studies directed at specific symptoms had a significantly greater yield. Electroencephalograms, gallium scans, thyroid scans, and mammograms were not useful as screening studies. Conversely, bone scans were positive in 46.5 percent of asymptomatic patients and in 88 percent of symptomatic patients. Chest roentgenograms were suggestive of malignant tumors in 43.6 percent of patients. Results of liver scans were predictable on the basis of changes in the alkaline phosphatase level and clinical liver examination. History and physical examination should clearly document the stage of disease, evaluate possible primary sites, and rule out impending acute complications. Chest roentgenograms and bone scans should be obtained early and open biopsy of accessible lesions scheduled promptly. Efforts should be directed at ruling out the more treatable malignant tumors. Further work-up is then indicated only by the development of specific symptomatology. Since median patient survival after initial presentation is only 6.6 months, prolonged hospitalization for numerous nonproductive diagnostic tests seems inappropriate.