RESUMO
We describe one case of Merkel cell tumor (MCT) of the eyelid diagnosed by fine-needle aspiration (FNA). The main cytologic features were: isolated cells, loose cohesive sheets, and rosette-like structures in a hematic background. The cells were round to ovoid and very uniform. Chromatin was finely granular and frequent mitotic figures were observed. Under close scrutiny small faintly stained juxtanuclear "caps" were seen. A strong dot-like positivity for CK22 and NFP was observed in the position corresponding to the "caps." NSE positivity was diffuse, although a weak dot-like positivity was seen in some cells. S-100 was negative. Both the cytologic features and the immunocytologic profile of Merkel cell tumor are very characteristic. FNA enables an early and confident diagnosis of this aggressive tumor and an early planning of surgery.
