Rare pediatric adrenocortical carcinoma with oncocytic change: a cytologic dilemma.

Pediatric adrenocortical carcinoma is extremely rare with a prevalence of 0.3 per million. Adrenocortical neoplasms in children usually present with one of the endocrine abnormalities. Adrenocortical neoplasms cannot be easily diagnosed on cytopathology; hence, the cytomorphological features posing diagnostic dilemmas are discussed in a pediatric patient presenting with palpable abdominal mass and virilization. Fine-needle aspiration smears were cellular showing cells in cohesive clusters adhering to central core of capillaries exhibiting an endocrine vascular pattern along with single cells and stripped nuclei. Cells were polygonal in shape and had abundant cytoplasm with well-defined borders and round eccentric nuclei with prominent nucleoli. Marked anisonucleosis was also noted. Few cells showed abundant granular cytoplasm resembling oncocytes. Many bizarre and multinucleated cells, few mitotic figures, and necrosis were also seen. Hematoxylin and eosin-stained sections of tumor biopsy suggested possibility of adrenocortical neoplasm. A panel of immunohistochemical markers were used to exclude possibility of renal cell carcinoma (RCC) and pheochromocytoma that showed vimentin (+), cytokeratin (-), inhibin-α (+), neuron-specific enolase (focally +), and chromogranin (-). The Ki67 index was 15%, and P53 was strongly positive. It is difficult to distinguish adrenocortical neoplasm, RCC, and pheochromocytoma on cytology because of overlapping features; hence, important cytological features which help in distinguishing between the three are discussed.