Figure 1. Hematoxylin-eosin staining of the tumor. Note that the tumor cells are non-cohesive and invade in a predominantly single file fashion. There is a marked desmoplastic response to the invasive tumor cells. Cytologically, the tumor cells are pleomorphic with eccentrically placed nuclei and homogeneous eosinophilic cytoplasm. The nuclei are irregular with clumped chromatin and irregular prominent nucleoli.