2019 Volume 33 Issue 3 Pages 260-264
Merkel cell carcinoma (MCC) is a highly malignant tumor that frequently occurs on the face of elderly patients. Many cases have been reported to be associated with other skin tumors. We experienced a case of MCC with Bowen's disease on a burn scar in which the neoplastic cells were negative for both CK20 and CK7. Summarizing the cases of MCC with Bowen's disease, the rate of CK20 positivity tends to be low. When diagnosing MCC, immunostaining for chromogranin A, synaptophysin, and CD56, is necessary. In addition, some reports indicate that cases of MCC associated with other epithelial tumors or those without expression of CK20 in neoplastic cells tend to be negative for Merkel cell polyomavirus. In these cases, sun exposure, immunosuppression, irradiation, and burns such as in this case may be involved as factors triggering onset.[Skin Cancer (Japan) 2018 ; 33 : 260-264]
