Radiotherapy is the important modality of treatment of cancers using high energy radiation such as X- Rays and Ƴ Rays. This treatment can be administered from outside the body (external beam radiotherapy) or internally (brachytherapy). External beam Radiotherapy is administered on specialised machines known as Linear accelerators. Most commonly, radiotherapy is delivered over 2 to 7 weeks, 5 days every week as per the clinical needs. The radiation is delivered to the cancer cells without affecting much normal body cells. It is a safe, non-invasive, less painful and effective method of cancer treatment. It does not involve exposure to any heat or any electrical instruments. It is similar to taking a diagnostic X ray which is given as treatment in radiotherapy with advanced machines. Strict guidelines and protocols are followed to prevent unwanted radiation exposure.
External radiotherapy is delivered by following techniques depending on the diagnosis and cancer site of the treatment.
Patient and the attendant are adequately explained and counselled about the radiotherapy planning and treatment. All necessary instructions and anticipated side effects as well as their management are discussed in details with patient. Some patients also receive chemotherapy alongwith radiotherapy.
Higher radiation dose can be given to cancer cells with least radiation to normal cells. The treatment duration is few days and is completed in shorter treatment time.
Depending on site of cancer and treatment, patients can have following toxicities. The common side effects seen in all site malignancies is
All above side effects are manageable with medications and can be reduced with proper counselling, treatment planning and instructions followed by patient as given by the doctor.
After the counselling, a body mask with a deformable sheet is made of the region of interest for the cancer directed treatment. This body mask is to hold the patient stable in treatment position.
The mask making is followed by a planning CT scan of the region of interest with or without contrast injection, after this the patient is sent home and is called upon the day of radiotherapy starting which is usually within 2 – 3 days. Meanwhile, the doctor marks the cancer and its possible spread areas slice by slice on the CT scan after which the physicist makes a treatment plan on the advance planning softwares, giving adequate treatment to target region and least minimum radiation to the normal tissues. The doctor evaluates the plans and approves the best one. A quality assurance test is done to confirm the planned treatment and then the patient is called upon for radiotherapy treatment.
Patient and attendant are again counselled and explained the treatment procedure. The advise on care and precautions to be taken during radiation treatment is given. Premedications, Dietary and chemotherapy instructions as per the diagnosis and need is explained. The patient is reviewed throughout the process for accuracy of treatment as well as any side effects are managed accordingly. Most of the side effects are manageable on opd basis, very rarely a patient may require hospital admission. At treatment conclusion a discharge summary is given to the patient that includes the treatment details of radiotherapy and follow up advice.
Brachytherapy includes delivering a high dose of radiation in and very close to the cancer cells. This is done with the help of placing specialized applicators through which a radiation source delivers the radiation. The applicators are inserted into the body cavities depending upon the site of malignancy.
Patient is counselled and explained the entire procedure. The applicators insertion is done under general anaesthesia, hence the patient is admitted prior to the procedure. After the application is done, a planning CT scan is taken for the brachytherapy treatment. Adequate analgesics are given to the patient till the treatment is delivered with applicators in position.
