November 2018 — Hematopathology

A 59-year-old man with a history of HIV presented with a 6 cm mass involving the left palatine tonsil. Biopsy of the mass showed the histologic findings seen below. Initial immunohistochemical stains including pankeratin, p63, and S100 were negative.

Additional immunohistochemical stains revealed the following immunophenotype:

This quiz is no longer available.
Rosalind Sharain, M.D.
Fellow, Cytopathology
Mayo Clinic
Linda Dao, M.D.
Consultant, Anatomic Pathology
Mayo Clinic
Assistant Professor of Laboratory Medicine and Pathology
Mayo Clinic College of Medicine
MCL Education (@mmledu)

MCL Education

This post was developed by our Education and Technical Publications Team.