Metastatic melanoma of the gallbladder: a case report and review of the literature.

A single case of symptomatic metastatic melanoma to the gallbladder, with roentgenographic findings of gallbladder disease, is presented. Review of the 12 previously reported cases of symptomatic metastatic biliary melanoma and of those reports of "primary" melanoma of the gallbladder reveals marked similarity between the two groups, with regard to relative size, pathologic description, number, and location of lesions. This, together with the finding of "junctional activity" in our case, leads us to believe that most if not all melanomas present in the gallbladder are metastatic deposits from a known, undetected, or regressed primary locus elsewhere. Surgical removal, even in the presence of disseminated disease, is a worthwhile palliative procedure.