Know about Intensity Modulated Radiotherapy(IMRT)

Cancer of the mouth and throat are the most common cancers in Indian males, because of the high incidence of smoking and chewing tobacco and the widespread use of pan masala. In fact, the diasporic Indian population has even led to an increase of cancer of the mouth in the Western world!

Cancer of the mouth usually presents as an ulcer on the cheek, gums or tongue and any blister / ulcer in these areas persisting for more than three weeks, warrants a visit to a doctor. The symptoms of throat cancer are a foreign body sensation in the throat, change in voice, painful swallowing persisting for three weeks. Both mouth and throat cancer may also manifest simply as a lump in the throat.

Radiotherapy is the treatment of cancers using x rays or other forms of electromagnetic rays that have the ability to destroy tissue by damaging the DNA of cells.

Radiotherapy is an integral part of the treatment of head neck cancer, having the ability to destroy cancer in this site, thus curing cancer of the mouth and throat. The probability of cure is excellent, with more than 90 % early vocal cord cancer patients getting cured and up to 70 % stage III and IV A patients getting cured.

Modern radiation techniques have led to a dramatic improvement in the quality of life of cancer patients undergoing radiotherapy. A technique called Intensity Modulated Radiotherapy, in use for a little more than a decade, has resulted in this dramatic change. This technique allows the radiation oncologist to target the cancer accurately and yet reduce the radiation dose to normal structures adjacent to the cancer.

Patients treated for head neck cancer without using IMRT have to change their diet to a liquid or porridge like diet, often also losing the ability to taste food forever. They also develop a permanently dry wood like mouth, being troubled by oral blisters and bad teeth.

Dr. Sapna Nangia, Cancer specialist at the Indraprastha Apollo Hospital, New Delhi, who has been working in the field of IMRT in mouth and throat cancer for more than a decade says that in contrast, patients treated with IMRT quickly regain normal taste and salivary function and have a good quality of life. They are also less likely to have dental problems following radiotherapy. Since dose to all normal structures is reduced with this treatment, there are fewer blisters during treatment, and less chance of scarring or damage to the jaw bone.

Dr. Nangia  strongly feels that in the interest of patients suffering from mouth and throat cancer , radiotherapy , whether being used alone or in combination with surgery or chemotherapy, should always be in the form of Intensity Modulated Radiotherapy. She feels that primary physicians, dental surgeon and ENT surgeons, who are often the people who first diagnose cancer of the mouth and throat, need to be aware of this advanced form of radiotherapy, so that they can guide their patients correctly. The general public , too, should be aware of the latest advances in the field of cancer treatment, a field in which rapid advances are taking place and which are available in India at the same time as they are in the western hemisphere.

What is IMRT?

Radiation oncologist’s expert uses this latest therapy, intensity-modulated radiation therapy (IMRT), to treat cancer. This advanced type of radiotherapy uses a computer-controlled device, called a linear accelerator, to deliver precise doses of radiation to tumors or specific areas within the tumors. IMRT, stops cancer cells from dividing and growing, thus slowing or stopping tumor growth. In many cases, radiation therapy is capable of killing all of the cancer cells. Using 3-D computed tomography (CT) images of the patient along with computerized dose calculations, IMRT allows for the radiation dose to conform more precisely to the three-dimensional shape of the tumor by controlling — or modulating — the intensity of the radiation beam. The therapy allows higher radiation doses to be delivered to regions within the tumor while minimizing the dose to the surrounding area.

The Advantage to Patients
· Higher and more effective radiation doses can safely be delivered to tumors with fewer side effects

· Reduced treatment toxicity.

Radiotherapy exactly targets the tumor and avoid healthy tissue, increasing effectiveness and reducing side effects.

Type of Cancer Treated with IMRT- Bone cancer, Brain tumors, Breast cancer, Gastrointestinal cancer, Gynecologiccancer, Head and neck cancer, Lung cancer, Prostate cancer, Spinal cord cancer.