Fig. 2
From: Metastatic squamous cell carcinoma of colon from esophageal cancer
Microscopic finding of the colon tumor. Biopsy by colonoscopy showed poorly differentiated squamous cell carcinoma with dense cytoplasm, irregular nuclear contours, moderate pleomorphism and prominent nucleoli (hematoxylin and eosin stain, ×40). Additional immunohistochemical study and comparison to prior tumor histology indicated metastatic rather than a primary colorectal carcinoma