09/30/2026
Can you identify the diagnosis?
A 34-year-old female presented with an enlarged left cervical lymph node.
Review the images and make your call. Answer at the bottom of this post.
This case was submitted by Jason L. Hornick, MD, PhD, faculty for Inside Thyroid Pathology in Three Days: All You Need to Know and Discover from the New Bethesda System to the WHO 5th Edition, November 16–18 at USCAP’s Interactive Center.
Learn more: https://buff.ly/jmpX0rn
Answer: Follicular dendritic cell sarcoma
Follicular dendritic cell sarcoma may arise in lymph nodes or at extranodal sites, with cervical lymph nodes representing the most common location. At this site, this rare tumor may be mistaken for metastatic carcinoma, including anaplastic thyroid carcinoma, undifferentiated nasopharyngeal carcinoma, or HPV-associated squamous cell carcinoma.
Expression of EMA can add to the diagnostic challenge, although keratins are consistently negative. Helpful diagnostic markers include CD21, CD23, and CD35.
