Cytomorphologic and immunocytochemical diagnosis of primary hepatic angiosarcoma in a young adult: Challenging diagnosis of a rare, aggressive malignancy.

Primary hepatic angiosarcoma (PHA) is a rare, rapidly growing, highly aggressive hepatic malignancy, primarily seen in elderly males. Establishing an accurate clinical diagnosis is challenging owing to its rarity and nonspecific presentation. Rendering a cytologic diagnosis of PHA is extremely difficult, and immunocytochemistry(ICC) on cell block(CB) sections is essential to confirm the diagnosis. The characteristic cytomorphologic features of PHA have rarely been documented, further augmenting the diagnostic challenge. A 32-year-old male presented with abdominal pain, abdominal distension, and significant weight loss over the past 9 months. On examination, the abdomen was distended, with multiple spider angiomas and a large mass in the right hypochondrium. His renal function tests, liver function tests, and serum tumor markers were within normal limits. An abdominal triphasic computerized tomography revealed a large lobulated mass in the right lobe with central necrosis. An ultrasound-guided FNA was performed from the liver lesion. The cytologic smears showed singly scattered large, markedly pleomorphic, epithelioid-elongated tumor cells having oval-elongated nuclei, irregular nuclear contours, coarse chromatin, prominent macronucleoli, and abundant finely vacuolated cytoplasm in a background of blood. ICC on the CB demonstrated diffuse positivity for vimentin, CD31, and nuclear positivity for FLI-1, confirming a vascular origin. Hence, a final cytologic diagnosis of primary hepatic angiosarcoma was rendered. The index report describes the characteristic cytomorphologic and immunocytochemical features of a rare hepatic malignancy in a young male and reiterates the usefulness of FNAC coupled with CB-ICC in the quick and precise diagnosis of such challenging cases.