June 15, 2022
Dr. Kinjal Jani, Director and Head of Department of Radiation Oncology, HCG Cancer Centre, Ahmedabad.
The common cancer treatments are Surgery, Radiotherapy or Chemotherapy. The treatment option depends on the organ affected and the stage of the disease. Some cancers require only one of the treatments, while some may require a combination of treatments. There has been a lot of advancement in technology leading to early diagnosis, better cure rates and reduced complications. The newer techniques of Radiotherapy include IMRT, IGRT, SBRT, Tomotherapy, CyberKnife therapy and Proton therapy.
Treating Cancer with Radiation Therapy
The majority of the early cancer cases require treatment with surgery either alone or along with other therapies, such as radiation therapy and chemotherapy. However, people do not know that many cancers do not require surgery and can be treated with radiation therapy alone or radiation therapy with chemotherapy. Some of these cancers include:
Larynx (Vocal Cord) Cancer
When the technology was not much developed, doctors performed the surgery and removed the vocal cords to manage this cancer type and prevent its progression. However, radiation therapy can help in avoiding surgery in stages I, II and III of larynx cancer. The radiation therapy also saves loss of structure and function of vocal cords. So the patient does not have to lose their voice.
Radiation therapy has a 90-95% success rate in stage I, 85-90 % success rate in stage II, and 75-80% success rate in stage III. After radiation therapy, the patient is advised to visit the doctor for follow-up every three months. The oncologist may also suggest an endoscopy to monitor the effectiveness of treatment and if there is any recurrence of cancer. In some cases, the healthcare professional asks the patient for a full-body scan to rule out the spread of cancer.
Nasopharyngeal cancer affects the nasopharynx. It is present behind the nose and above the throat. The main treatment for nasopharyngeal cancer is radiation therapy along with chemotherapy. Surgery is quite difficult in patients with this cancer due to the location of the tumour.
There are different techniques of radiation therapy used in the management of nasopharyngeal cancers, and they include IMRT, IGRT or Proton Therapy. For some recurrent cases, we can use SBRT or Brachytherapy also. All stages of nasopharyngeal cancer can be treated with chemoradiation with a high success rate.
Anal Canal Cancer
Anal canal cancer comprises approximately 10% of the total cancers in the anorectal region. Radiation therapy in anal canal cancer is considered an organ-preserving treatment. It is because the conventional treatment for anal canal cancer comprises abdominoperineal resection (APR Surgery). In this method, the surgeon removes the lower part of the colon, the anus and the rectum. After the abdominoperineal resection, the doctor performs a colostomy. During this procedure, the surgeon brings the lower part of the colon outside the body through the abdominal skin. The quality of life is significantly reduced after a colostomy.
With the advancements in radiation and chemotherapy, the anal canal tumour can be treated successfully, while sparing patients from permanent colostomy. In some cases, where primary tumours < 4 cm, radiation alone may also have a good success rate in managing the tumours of the anal canal. Chemoradiation is effective in managing all stages of anal canal cancer. The quality of life is significantly improved as there is no abdominoperineal resection and colostomy.
Lung cancer tops the list of causes of cancer deaths globally. Radiation therapy is used to manage stage I lung cancer by a technique called Stereotactic Body Radiotherapy (SBRT). Administering radiation therapy in combination with chemotherapy (chemoradiation) helps manage stage II and III lung cancer with a high success rate. Further, it is not only effective in managing early-stage lung cancer but also delays the progression of advanced lung cancer.
Advanced radiotherapy techniques prevent damage to surrounding normal tissues, and patients have a better quality of life. Further, stereotactic body radiation therapy and stereotactic ablative radiation therapy also effectively kill cancer cells when the tumour is small.
Radiation therapy is also effective in managing tonsil tumours. Treating tonsil tumours through surgery in adults is challenging, and may have several complications. Radiation therapy is effective in treating early-stage tumours, wherein the cancer cells have not spread beyond the tonsils. Further, the doctor may also combine chemotherapy with radiation therapy to improve effectiveness in locally advanced tumours. It is because chemotherapy makes the cancer cells more vulnerable to radiotherapy.
Side Effects of Radiation Therapy
Radiation therapy may have some side effects; however, most of them are temporary. These side effects are limited to the area treated and are managed through medications. These are:
- Diarrhoea and local irritation while passing stool and urine when treating anal cancer or other cancers of the pelvic region
- Mouth ulcers, difficulty in swallowing, cough, skin irritation etc., when H & N radiotherapy is given
- Patients may experience fatigue and tiredness because of a lack of appetite.
- Thinning of hair or hair loss occurs in the area that is treated with radiation therapy
Preventing Cancer Recurrences through Radiation Therapy
Radiation therapy not only treats cancer primarily but also reduces the chances of recurrences. Sometimes, doctors prefer radiation therapy either before (neoadjuvant) or after (adjuvant) the surgery. Before the surgery, it helps shrink the size of the tumour, while after surgery, it removes the cancer cells left that were not eliminated during surgery. It has an essential role in preventing the recurrence of breast cancers and head and neck cancers.
Radiation therapy is a mainstay treatment for early-stage cancers as well as advanced cancers. However, it is important that the patients should identify the early signs of cancer and consult a doctor nearby for early diagnosis and better cure. Radiation therapy has localised and temporary complications, which are easily manageable with medications. It helps in preserving the functional status of the organs, unlike surgery. The majority of the cancers are treated by radiotherapy either alone or in combination with surgery or chemotherapy.
– By Dr. Kinjal Jani, Director and Head of Department of Radiation Oncology, HCG Cancer Centre, Ahmedabad.