An Aggressive Case of Adrenocortical Carcinoma Complicated by Paraneoplastic Cushing's Syndrome.

Adrenocortical carcinoma (ACC) is a rare endocrine malignancy with a poor prognosis. Surgical resection may be curative if localized disease is identified, although recurrence is common. Research shows that the use of adjuvant therapeutic regimens such as EDP-M (combination of mitotane, etoposide, doxorubicin, and cisplatin) in high-risk patients has survival benefits. A 75-year-old female was incidentally found to have a right adrenal heterogeneous internal enhancement measuring 5.0 x 3.7cm. The workup confirmed autonomous adrenal production of corticosteroids and she was referred to surgery for an adrenalectomy. A T2 ACC with positive margins and lympho-vascular invasion was resected, following which she was started on external beam radiation followed by four cycles of carboplatin and etoposide. Despite initial treatments, she was diagnosed with refractory metastatic disease at subsequent follow-ups. Pembrolizumab immunotherapy was started, but disease progression continued, and she was eventually transitioned to mitotane 1g twice daily. She continued to worsen and was eventually transitioned to hospice care. The management of ACC remains diagnostically challenging, especially because most patients do not present until an advanced stage of disease. Surgery is commonly employed with a curative intent, and opinions regarding adjuvant cytotoxic therapy and/or radiotherapy remain mixed.