A 54-year-old man presents with an enlarged supraclavicular lymph node on the left side. On palpation, the node is painless and stony hard. The node biopsy reveals anaplastic cells that are keratin positive. Which of the following is the most likely origin of the cells detected on the biopsy?

Question

Quizplus · Accepted Answer

Eductional Objective: Keratins are a type of intermediate filament found in epithelial cells. Pathologists use immunohistochemistry stains with keratin markers to identify poorly differentiated tumors or tumors with an unknown site of origin. Carcinomas, mesotheliomas, thymomas, various sarcomas, trophoblastic tumors, and desmoplastic small round cell tumors all stain positive for keratin.

A 54-Year-Old Man Presents with an Enlarged Supraclavicular Lymph Node