Oncocytic Adrenocortical Neoplasm with Concomitant Papillary Thyroid Cancer.

Adrenal oncocytoma (AO) is an extremely rare adrenocortical neoplasm and little is known about its malignant potential, secretory properties, and hereditary origin. We present the case of a benign AO with concomitant incidentally found papillary thyroid cancer (PTC) and review similar cases in the literature. Immunohistochemistry and next-generation sequencing (NGS) were performed. A 66-year-old women was incidentally found to have a large, androgen-secreting right adrenal mass. F-18-Fluorodeoxyglucose positron emission tomography showed intense uptake (SUVmax 88.7) of this mass and found a hypermetabolic right thyroid mass. Open adrenalectomy was performed for this highly suspicious adrenal mass. Histopathology revealed benign AO that was BRAF(V600E) negative, with low Ki-67, and no somatic mutation found on NGS. Thyroidectomy revealed invasive, BRAF(V600E)-positive PTC. At 6 months follow-up, androgen levels returned to normal, and no recurrence was seen on imaging. To our knowledge, this is the first report of an androgen-secreting AO with concomitant PTC. Possibly the simultaneous discovery of two independent neoplasms was observed. In conclusion, this case highlights that care should be given to exclude concomitant neoplasms. Long-term and regular imaging with biochemical follow-up is warranted, since the outcome and clinical behavior of AO remains uncertain.