Background Adrenocortical carcinoma (ACC) is a rare malignancy that is challenging to diagnose and has important implications for surgeons who approach this disease. Despite its rarity, it must always be in the differential diagnosis when investigating and treating large adrenal masses. We aim to demonstrate the complexities of this disease through a review of five recent patients at a single tertiary care center. Methods A series of five patients are described, each of whom presented to a single institution as referrals for "large adrenal mass" in the past sixteen months. Their pre-operative diagnosis, radiographic findings, the operative approach and the pathology results were examined. Results The first patient had a 12 cm high grade adrenocortical carcinoma. The second patient had pathology consistent with a 9 cm, high grade ACC. The third had a liposarcoma. The fourth patient had a myelolipoma. The fifth was diagnosed with a benign process. Conclusion Although adrenocortical carcinoma is an uncommon cancer, it has significant implications for the patient's prognosis and ultimately, their treatment algorithm. Therefore, when evaluating large adrenal masses, surgeons must remain vigilant of the possibility of adrenocortical carcinoma.