<prompt> Radiotherapy is most useful in:SeminomaMelanomaOsteosarcomaPancreatic carcinoma  <response>: Ans. A. SeminomaSeminoma is a highly radiosensitive tumor and hence radiotherapy is commonly used for treatment.Radiosensitive and Radioresistant TumorsHighly radiosensitive tumors are Lymphoma Seminoma Myeloma Ewings sarcoma Wilms tumorHighly radioresistant tumors are Melanoma Osteosarcoma Pancreatic carcinoma Hepatic carcinoma Renal cell carcinoma 