<prompt> Radiotherapy is most useful in which of the following: March 2010ChoriocarcinomaOsteosarcomaSeminomasRenal cell carcinoma  <response>: Ans. C: Seminomas Radiotherapy may be effective alone, or may require the addition of cytotoxic chemotherapy as in the more advanced stages of a Wilms tumour and Hodgkins disease. Radiosensitive tumor includes: Malignant lymphomas Seminomas Medulloblastoma Neuroblastoma Wilms tumour Early cervical carcinoma Vaginal carcinoma Most head and neck tumours Radioresistant tumours are those that do not respond to radiotherapy. This group includes: Osteosarcoma Fibrosarcoma Liposarcoma Myosarcoma Malignant melanoma Large bowel adenocarcinomas Gliomas 