Case 34

Author: Dr. Manon Auger, Dept of Pathology, McGill University, Montreal, Canada

Reviewer: Ritu Nayar, MD., Northwestern University, Feinberg School of Medicine, Chicago, IL, USA

G. Malignant: Squamous cell carcinoma (this is a poorly differentiated squamous cell carcinoma)

A 79 year old man presented with a 2cm nodule in the lingula; no other significant past medical history. 

Which of the following is the most likely diagnosis?