March 2022 — Vol 142 No 3

Addressing the Origin of Virus-Negative Merkel Cell Carcinoma

Merkel cell carcinomas (keratin 20 (K20) and chromogranin (CHGA) positive, TTF1 weakly positive) are associated with squamous cell carcinomas (keratin 5/6 (K5/6) positive) relatively frequently. Kervarrec and co-workers carried out whole-exome sequencing of dissected tumor fragments and determined that Merkel cell polyoma virus-negative MCC share many mutations with adjacent SCC. The authors conclude that MCC and SCC can share a common keratinocyte ancestor. See pages 516-527 for more details