-I'm not sure what you are asking for. Radiotherapy is radiation therapy. You are radiated with X-Rays, or other particles (Protons, Neutrons) that kill tumors to which the beam is aimed at. Problem is that it also kills healthy tissue that the beam passes through either in front of the tumor, or behind the tumor.

Chemotherapy is a chemical that is supposedly somewhat selective to kill tumor cells. It also kills some healthy tissue. It is usually, but not always, given intravenously.

If you are asking about how someone responds to the two, generally, radiation is only given when the tumor is localized. That is restricted to the organ it originated from (Ex. Breast, Kidney, Prostate, etc). Once it has spread beyond the organ, radiation is not the best choice, and that's where chemotherapy comes into play. However, there is a maximum dose of radiation that you are allowed to receive in a lifetime. Once that dose is reached, no more radiation.

-Chemotherapy is the process of using pharmaceutical or chemical combinations to kill cancer cells and dissolve tumors. It is usually administered by intravenous injection into the arm or a permanent catheter implanted into the shoulder normally. Some of the commonly used chemotherapy drugs are 5FU, adriamycin, cisplatin, Taxol, and many others. Some chemotherapy may be taken by mouth in the form of a pill or capsule. The type of chemotherapy you will receive depends on the type of cancer you have and the stage of your cancer. Sometimes chemotherapy is given before surgery to shrink a tumor, and sometimes it is given afterwards to clean up any remaining cancer cells in the body.

Radiotherapy is the process of applying highly irradiated beams directly to an area of tumor growth, or the area in which a tumor may have already been removed by surgery. Radiotherapy usually will clean up any remaining cancer cells left by chemotherapy, but radiotherapy can be used alone without primary chemotherapy.

The amount of chemotherapy and/or radiotherapy is dependent on the type of cancer, the stage of the cancer, the patient's weight, and other factors.