Merkel cell carcinoma of the thigh: case report and review of the literature

BACKGROUND: Merkel cell carcinoma (MCC) is a kind of cutaneous neuroendocrine cancer with a poor prognosis. It is characterized by a high rate of recurrence and metastases, including distant metastases and regional nodal metastases. Clinically, MCC often manifests as obvious single painless hard nodules visible in sun irradiation of diameter <2 cm and not uncommonly >2 cm, with rapid growth and metastases, especially lymph node metastases. Due to the aspecific nature of MCC, it is often confused with other skin cancers. Exploring different treatments of MCC is necessary. CASE PRESENTATION: The current study describes the case of an 86-year-old retired man, who presented with a 2.5×2.0×1.2 cm red nodule on the right thigh, which was initially diagnosed as subcutaneous small cell cancer. Upon histological and immunohistochemical analysis, the tumor was consistent with a diagnosis of MCC. RESULTS: Antiangiogenic therapy combining endostar and apatinib was administered and a partial response achieved after 2.0 months of treatment, and 6.5 months of progression-free survival was achieved. Overall survival was 13.0 months. CONCLUSION: We believe that antiangiogenic therapy is an extremely effective treatment for MCC, especially for patients who cannot tolerate chemotherapy and radiotherapy.