Metastatic Adrenocortical Carcinoma to the Skin: A Case Report and Review of This Unusual Neoplasm

Adrenocortical carcinoma is a very rare oncologic condition with poor prognosis that usually metastasizes to the lungs, liver, local lymph nodes, and peritoneum at initial presentation. However, skin metastasis is very uncommon and has rarely been reported even in advanced stages of the disease. We present a case of a 41-year-old man with a known history of adrenocortical carcinoma of the right adrenal gland that presented with an arm mass. The histopathologic sections showed a multinodular necrotic malignant neoplasm in dermis and subcutaneous fat composed of atypical epithelioid cells with ample granular cytoplasm and pleomorphic vesicular nuclei with frequent intranuclear inclusions and atypical mitoses. The immunohistochemical stains showed tumor cells that were strongly positive for synaptophysin and inhibin, only focally positive for Melan-A, and negative for AE1/AE3. The histopathologic features and the immunohistochemical profile confirmed the diagnosis of metastatic carcinoma consistent with adrenal cortical origin. The diagnosis can be difficult (especially when no clinical data are provided), and an immunohistochemical battery is often useful in distinguishing this tumor from other tumors with similar cytomorphological features.