Clinical features and management of Merkel Cell Carcinoma

Merkel cell carcinoma (MCC) is an aggressive dermal tumour of neuroendocrine origin. MCC is a rare tumour and all information pertaining to its behaviour, therapy and prognosis is based on retrospective reports. The two potentially curative treatment modalities are surgery and radiotherapy. It is a rare, highly malignant primary skin tumour, originally called "trabecular carcinoma" of the skin. MCC poses a challenge to the clinician because of its rarity and poor prognosis. The optimal therapy is customised and tailored for each individual patient with the appropriate use of operative resection and radiation therapy. This review covers reports from several authors regarding the rationale of using postoperative radiotherapy to the primary tumour and regional lymphatics. Although MCC is classified as a type of neuroendocrine carcinoma, it is less likely to be controlled by systemic chemotherapy. Management of primary lesion with clinically localised disease is wide excision with margin of at least 2 cm whenever possible. MCC is a radiosensitive tumour, adjuvant radiotherapy has been advocated in order to control local as well as regional disease Radiation induced toxicity should be considered and discussed with the patient. Adjuvant radiation to the nodal bed after complete lymphadenectomy in patients with metastatic disease is generally not recommended.