Pheochromocytoma - Cytologic findings on intraoperative scrape smears in five cases

BACKGROUND: There have been few studies describing the cytology of adrenal pheochromocytoma (PC). Although needle aspiration (FNA) for a preoperative diagnosis of PC is generally considered a contraindication, this tumor can be an unsuspected finding in adrenal FNA performed for other reasons. STUDY DESIGN: Scrape cytology smears prepared in five cases of PC were exam ined for different cytomorphologic features. The results were correlated wi th the corresponding permanent histologic sections. RESULTS: Previously described features, like cellular smears showing cells with abundant, poorly defined fragile cytoplasm, bare nuclei, anisonucleosi s, "salt and pepper" chromatin, variable nucleoli and few ganglion cell-lik e cells, were noted. In addition, several previously unreported cytologic f eatures were observed: (1) loosely cohesive PC cells along a ramifying, del icate central core; (2) intracytoplasmic microvesicular (not hyaline/homoge neous) globules; and (3) different arrangements of capillary-stroma and PC cells (Zellballen pattern; empty capillary rings; stroma with adherent, int act PC cells or fragments of disrupted PC cell cytoplasm). CONCLUSION: The cytologic appearance of PC may resemble that of other neuro endocrine tumors; however, it can be diagnostic when combined with proper c linical data and ancillary tests.