Merkel Cell Carcinoma (MCC) of the skin is a rare, aggressive skin cancer of neuroendocrine origin which occurs in sun exposed areas of the skin, predominately in the older population. It has the propensity for dermal lymphatic spread as well as nodal and haematogenous spread. Merkel cell polyoma virus has been implicated as a viral cause although there remains some uncertainty as to exact role. MCC exhibits intrinsic sensitivity to ionizing radiation and chemotherapy.

Optimal treatment outcomes can be achieved with early diagnosis and an integrated approach with surgery, radiation +/- chemotherapy. The 5 year disease specific survival and loco-regional control for all patients in Queensland from 2000-2005 was 68% with 73% respectively. Approximately 80% of patients will have the disease excised and radiotherapy is most commonly delivered for microscopic disease. There are some data indicating that radiotherapy alone may sterilise gross macroscopic disease with an infield control rate of 75%. Adjuvant radiotherapy has been shown in the large SEER data base to improve the median survival of MCC from 45 months to 63 months and should be adopted as part of the standard of care for Stage I and III MCC. The nodal basin requires assessment with imaging and careful clinical evaluation. The role of PET imaging is currently being evaluated as MCC has high levels of avidity for 18-FDG. The primary site should be included in the radiation volume if the primary site has not been widely cleared and the nodal basin should be included unless sentinel node biopsy was negative. The role of chemotherapy for locally advanced disease remains uncertain but may be used to palliate metastatic disease.

In conclusion, an integrated multidisciplinary is required in the management of MCC in order to achieve the optimal balance in tumour control, function and cosmesis.