REPORT OF A CASE
An 88-year-old white man presented with a 1-month history of an asymptomatic, rapidly enlarging nodule on his right cheek.The physical examination revealed a 2-cm firm, pink-to-red, lobulated tumor with a slightly yellow center on the right cheek (Figs 1 and 2). Palpable cervical lymphadenopathy was present on the right side. The remainder of the physical examination was unremarkable.A biopsy specimen was obtained for routine light microscopy (Figs 3 and 4). In addition, special immunocytochemical staining techniques were performed.What is your diagnosis?
DIAGNOSIS:
Merkel cell carcinoma, with presumed metastasis to regional lymph nodes.
HISTOPATHOLOGIC FINDINGS AND CLINICAL COURSE
Routine hematoxylin-eosin-stained sections showed the neoplasm to be nodular and focally pseudocystic. It was composed of small and large round cells arranged diffusely, in trabeculae and pseudoglandular structures (Fig