This study aims to develop a well-tolerated chemo-radiotherapy treatment for patients with Merkel Cell Carcinoma (MCC) of the skin, which achieves high rates of cancer control. The researchers will be looking at patients' quality of life in those receiving chemotherapy via a questionnaire that will be completed periodically throughout treatment and the follow-up after. The researches will also be looking at the value of using Positron Emission Tomography (PET – a type of imaging procedure that allows us to see anatomical structure and function that cannot usually be seen on a CT scan) to assist in tailoring the Radiation Therapy (RT) treatment plan to the extent of each participants disease.