Although metastatic melanoma is most frequently found in liver, lungs, and brain, most metastases found in the gallbladder are from melanoma. Here, we present a case of isolated metastatic melanoma found during cholecystectomy.
74-year-old male with a personal history of hypertension, diabetes mellitus, obesity, and arrhythmia. A skin lesion was found on the right malar region. An excisional biopsy was performed and histopathological examination showed an ulcerated nodular-type malignant melanoma, Breslow 7.6 mm, Clark IV. Surgical excision with margins of 2 cm and sentinel lymph-node biopsy was carried and were negative. Abdominal sonography at 6 months showed an 18 mm solid mass adhered to the wall of the gallbladder that was suggestive of a polyp. Thorax-abdomen-pelvis CT showed no abnormalities. The gallbladder lesion had increased in volume on the following sonography and therefore, cholecystectomy was performed. Histopathological study revealed melanoma infiltrating the mucosa and muscular layer. Written informed consent was previously obtained, and Institutional Review Board approval was not needed.
Isolated metastatic melanoma in the gallbladder is uncommon. Follow-up controls with images are important in the diagnosis. As most metastatic melanoma to the gallbladder are asymptomatic, surgeons should have high level of suspicion. Cholecystectomy could prolong survival in these patients.
Isolated gallbladder metastasis of melanoma is an uncommon presentation of this disease. Laparoscopic cholecystectomy is an adequate procedure in this particular situation and may improve patient survival. The presentation of this case may help surgeons to maintain a high level of suspicion regarding the condition.

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