The term "throat cancer" describes cancers that arise from any of the structures in the throat, mainly the pharynx, the larynx or voice box and the epiglottis.
The American Cancer Society lists radiotherapy or radiation therapy as one of the three main options of treatment in patients with throat cancer. The other options are surgery and chemotherapy. Radiotherapy involves the use of high energy particle rays to kill cancerous cells or stop them from growing. Several forms and applications of radiation therapy are used to treat throat cancer.
External Beam Radiation Therapy
External beam radiation therapy involves the generation of high energy x-rays, gamma rays or electrons by a machine placed outside the body. The radiation is focused on the areas affected by the cancer. There are usually daily sessions five times a week, repeated over five to seven weeks in the usual schedule, according to the ACS.
Advances in technology have led to the development of more precise modes of delivering the radiation to cancerous areas, sparing normal surrounding tissue. Those mentioned by the Johns Hopkins Head and Neck Cancer Center are Intensity- Modulated Radiation Therapy, IMRT and Image-Guided Radiation Therapy, IGRT. The Cancer Treatment Centers of America also describes the 3-Dimensional Conformal Radiation Therapy, 3D-CRT, and Highly Integrated Adaptive Radiotherapy, HI-ART, in the treatment of hard-to-reach throat cancers.
Internal Radiation Therapy
This type of radiation therapy, also called brachytherapy, involves the use of needles, catheters or wires to deliver sources of radiation very close to or directly into the cancer. According to the ACS, it may be combined with external forms of radiation therapy. There are generally two methods, high dose rate, HDR, and low dose rate, LDR, brachytherapy. Generally, internal radiation is not preferred in throat cancers radiotherapy.
Radiotherapy Applications
Radiation therapy can be used alone as the main treatment in small tumors, especially in people too sick for surgery or as an alternative to removal of the voice box. According to the ACS, in larger tumors, radiation therapy can be combined with chemotherapy for increased effectiveness.
In some cases, radiation therapy is used after surgery to clear any missed cancer cells. Here, it is called adjuvant radiotherapy.
Some large or complicated cancer masses may require radiation prior to surgery to shrink the cancer mass and simplify the surgical removal. This type of radiation is called neoadjuvant radiation therapy.
In terminal cases and metastatic disease, radiation therapy, with or without chemotherapy, is used to reduce pain and discomfort and preserve some function. These measures are geared toward improving the patient's quality of life. Here, it is called palliative radiotherapy.
