Sometimes this can be accomplished by surgery, but the tendency of cancers to invade adjacent tissue or to spread to distant sites by microscopic metastasis often limits its effectiveness. The success of chemotherapy is often limited by toxicity to other tissues in the body. Radiation can also cause damage to normal tissue.
Identifying causes of cancer and developing strategies for prevention, diagnosis, treatments and cure of it ,form the major objectives of cancer research. Cancer research ranges from epidemiology, molecular bioscience (bench research) to the performance of clinical trials to guage and correlate applications of the various cancer treatment. These applications include surgery, radiation therapy, chemotherapy and hormone therapy, and combined treatment modalities such as chemo-radiotherapy. The attention in clinical cancer research has shifted towards therapies derived from biotechnology research, such as immunotherapy and gene therapy, since the 1990s.
The effectiveness of the various different cures and treatments for cancer can be analysed individually. According to the American Cancer Society, surgery is the oldest form of cancer treatment. It also has an important role in diagnosing and finding the extent of cancer. Advances in surgical techniques have allowed surgeons to successfully operate on a growing number of patients. Today, less invasive operations often can be done to remove tumors while saving as much normal tissue and function as possible.
Surgery offers the greatest chance for cure for many types of cancer, especially those that have not spread to other parts of the body. Most people with cancer will have some type of surgery. While different types of surgeries are performed in relation to cancer, it is curative surgery that is done to treat cancer primarily. Curative surgery is done when a tumor appears to be confined to one area and it is likely that all of the tumor can be removed. It may be used alone or along with chemotherapy or radiation therapy, which can be given before or after the operation. Sometimes radiation therapy is actually used during an operation. This is called intraoperative radiation therapy.
The medical use of ionizing radiation as part of cancer treatment to control cancer cells is called radiotherapy . Radiotherapy may be used for curative or adjuvant cancer treatment.
Chemotherapy refers to the use of antineoplastic drugs to treat cancer. Tumors with high growth fractions (such as acute myelogenous leukemia and the aggressive lymphomas, including Hodgkin's disease) are more sensitive to chemotherapy as chemotherapy affects cell-division and also as a larger proportion of the targeted cells are undergoing cell division at any time. Malignancies with slower growth rates, such as indolent lymphomas do not respond as well to chemotherapy.
According to Wikipedia,hormonal therapy is one of the major modalities of medical treatment for cancer. Hormonal therapy involves the engineering of the endocrine system