Merkel cell carcinoma - neuroendocrine carcinoma of the skin, treatment

Abstract

Merkel cell carcinoma (MCC) is a very rare form of the skin cancer with an aggressive biological behavior. The annual incidence is estimated to be 0.23 per 100,000 white population. Most cases occur in elderly people, with the average age of presentation being 69 years. MCC occurs most commonly in areas of the body that are exposed to the sun, with 50% occurring in the head and neck region and about 40% occurring in the extremities. MCC typically appears as a red nodule with a shiny surface, often with overlying telangiectasia. Regional nodes are involved in about 50% of the patients. Secondary sites of involvement include the skin (28%), liver (13%), lung (10%), bone (10%), and brain (6%). Wide surgical excision of tumor and regional lymph nodes with chemotherapy and radiotherapy is the treatment of choice and is according to stage of disease. The following are recommendation based on early stage of disease, stage IA and IB should be treated with surgical excision, in localization of head and neck with radiotherapy. Stage II disease, requires excision followed by postoperative radiation to the primary site and for the nodal mass. The treatment intent in stage III disease is purely palliative and most often requires systemic chemotherapy. Radiation can be used to palliate bony, brain secondary tumours, and to offer palliation with advanced cutaneous deposits that are bleeding.