Cytomorphologic spectrum in aspirates of extra-adrenal paraganglioma

Paraganglioma is a rare tumor arising from clusters of neuroendocrine cells in association with sympathetic and parasympathetic nervous system. It poses a diagnostic challenge because of its widespread anatomic distribution, subtle clinical manifestations, and a variety of morphologic patterns.

The aim of this study is to have an insight into the diverse morphologic spectrum of extra-adrenal paraganglioma (EAP).

A retrospective analysis of seven cytologically diagnosed cases of EAP over a period of 10 years was performed. There were five superficial swellings and two deep seated retroperitoneal masses. The superficial swellings were aspirated directly, and the retroperitoneal masses were aspirated under ultrasound guidance using 22-gauge lumbar puncture needle fitted to a 10 mL syringe. Smears were reviewed for cellularity, pattern, cell shape, cytoplasm, nuclear features, and background.

The age of patients ranged from 25 to 75 years; four patients were males and three were females. Sites involved were carotid body region (four cases), para-pharyngeal space (one case) and para-aortic region (two cases). All the cases yielded hemorrhagic material on fine-needle aspiration. Smears showed scattered and clusters of cells and loosely cohesive acini of tumor cells. Cells were round to polygonal with pleomorphic nuclei, granular chromatin, inconspicuous nucleoli, and moderate to abundant cytoplasm containing fine pink granules and vacuolations. The cases were confirmed on radiology and histopathology.

The cytologic features in EAP along with pertinent clinicoradiologic findings help in making an accurate preoperative diagnosis of an otherwise rare tumor.