A "tumour trifecta:" myelolipomata arising within an adrenocortical adenoma ipsilateral to a synchronous clear cell renal cell carcinoma

ABSTRACT

We present an intriguing case of adrenal myelolipomata occurring within an adrenocortical adenoma in concert with an ipsilateral clear cell renal cell carcinoma. A 50-year-old female presented with dull right flank pain and hematuria. Computed tomography indicated a 2.5 cm right renal mass as well as a 5 cm right adrenal mass. Both masses were surgically resected concurrently. Histology of the renal mass was consistent with conventional clear cell renal cell carcinoma, Fuhrman grade III. There was no extra-renal extension or lymphovascular invasion. The adrenal mass was a cortical adenoma with solid and nested patterns, with discrete zones consisting of erythroid, myeloid and megakaryocytic cells intermixed with mature adipocytes. Mitoses were inconspicuous. The solid tumour component was strongly positive for vimentin, inhibin and CD56, focally positive for low-molecular-weight cytokeratin (Cam 5.2), calretinin and CD10 (chiefly in the myelolipomatous zones), and negative for chromogranin, S100, HMB-45, melan-A (A103), Mart-1, synaptophysin, SMA, CK7, CK20, ER, PR, TTF-1, CD99 and GCDFP (BRST-2). Ki67 (MIB1) staining indicated a low tumour proliferation index. Although well-described individually, a search of the English language literature suggests that this is the first such documented case of synchrony of these three lesions. We also present a relevant review of the literature pertaining to adrenal lesions. In particular, we emphasize the epidemiological, histological and immunohistochemical features that are helpful in determining the origin and malignant potential of adrenal lesions.