Author: Richard Cantley, MD. Cytopathology Fellow, McGaw Medical Center, Northwestern University, Chicago, USA
Reviewer: Ajit Singh Paintal, MD. Assistant Professor of Pathology, Northwestern University, Feinberg School of Medicine, Chicago, USA.
A 55 year old woman with no significant past medical history presents with a large left renal mass. An ultrasound-guided fine needle aspiration of the mass was performed.
What is your diagnosis?