Melanoma of the gallbladder.

Melanoma is a highly malignant neoplasm with the most typical primary locations in the skin and eyeball and rarely reported in the other organs, including the gallbladder. More commonly metastases of melanoma of various primary sites to the gallbladder are observed. However, generally melanoma of the gallbladder is a rare entity with only 217 cases reported in the literature up to date. The paper summarizes knowledge on epidemiology, symptoms, laboratory and imaging findings, morphology, treatment options, and outcome of patients with both primary and metastatic melanoma to the gallbladder.