Melanoma of unknown primary origin presenting as a rapidly enlarging adrenal mass

Metastasis to the adrenal can be seen in the context of metastatic melanoma, but primary adrenal melanoma is very uncommon. We present a case of a rapidly enlarging adrenal mass that mimicked non-functioning primary adrenal malignancies but later proved to be part of a widely metastatic melanoma of unknown primary origin. Careful physical examination of the patient led to the discovery of a subcutaneous metastatic focus that was not seen on [(18)F]-fluorodeoxyglucose positron emission tomography/CT imaging. The presence of subcutaneous metastases raised the suspicion for metastatic melanoma; however, pathological confirmation remained the ultimate tool to reach the final diagnosis.