Cancer therapies are various modes of treatment, such as surgery, radiation therapy, and chemotherapy that are administered to cancer patients.

However, cancer treatments can pose several challenges, as therapies used to kill cancer cells are generally also toxic to normal cells. Moreover, cancer cells mutate rapidly and can develop resistance to chemical agents or radiation therapy. Besides, all types of cancer cells may not respond to the same therapy. Some cancer cells respond to one therapy, while some respond to another, reflecting different kinds of mutations present in different cancer cells. The type of treatment to be administered to a patient depends on the type of cancer and its stage of advancement. Therefore, while some patients can be treated with only one type of treatment, most cases need a combination of various therapies that can be either implemented together or over a period of time.

The combination of different treatment methods has many benefits over the use of a single treatment method:

1. One treatment method may be more effective at a certain stage of cancer, while another may be more beneficial at another stage. Therefore, using different therapies at different times during cancer treatment increases the likelihood of curing more than a single therapy.
2. Using different therapies at the same time can increase the overall effectiveness due to a synergistic effect and is, therefore, a competent strategy for treatment.
3. The use of a single therapy on tumor cells may need higher doses that can affect the healthy tissues and vital organs of the body. Administration of two therapy methods at once reduces the dosage and hence, causes lesser damage to the body.

For example, osteosarcoma or cancer of the bones was conventionally treated with limb amputation to prevent the spread of cancer cells to the rest of the body. However, the use of radiation therapy along with chemotherapy has been an effective treatment regime that can get rid of all cancer cells at once without the need for amputation.

Additionally, recent advances in cancer research have also led to the development of personalized medicine where treatment can be tailored according to the genetic changes in the patient during the course of cancer progression.