Treatment of lung cancer

BY: DR. JAYALAKSHMI PUBLISHED ON JANUARY 1, 2018

78 year old Mr. A was taken aback when a small spot in the right lung on chest X ray turned out to be a denocar cinoma (a type of cancer) after the biopsy. He had a number of associated health problems – COPD, diabetes, heart disease for which he had undergone bypass surgery 8 year back. He was considered very high anesthetic risk. He was advised surgery for the cancer, however due to the high anesthetic risk, he was not a suitable candidate and surgery was ruled out. He then heard about Cyber Knife treatment for lung cancer and opted for it. He underwent 3 sessions of treatment and his PET CT scan 3 months later is showing that the tumor has reduced by about 75%.

Who is the main culprit?

The primary risk factor for lung cancer is smoking tobacco, which accounts for most lung cancer related deaths. Cigarette smoke contains many cancer producing chemicals like nitrosamines and benzopyrenes. The risk for lung cancer increases with the number of packs of cigarettes smoked per day, and with the number of years spent smoking. Exposed non smokers also have an increased relative risk of developing lung cancer from second hand smoke. Stopping smoking brings down the risk of developing lung cancer. The decline is overall risk following stopping of smoking (called cessation) starts within 2-5 years of stopping smoking especially in people below 50 years of age.

What are the treatment options?

Surgery remains the gold standard of treatment in early stage lung cancers. However, there has been a search for nonsurgical, but curative treatment, more so in patients who are medically inoperable (that means the cancer as such is operable, however the patient cannot undergo surgery due to anesthetic risk), and in patients with a small tumors which has recurred (come back) after prior treatment. These are patients who earlier hit the dead end – now, Cyberknife treatment (called SBRT or SABR in lung) is an easy, non invasive therapy available with proven and equal efficacy in these patients. The effectiveness of Cyberknife treatment has made it a treatment option in early stage node negative non small cell lung cancers that are medically inoperable and has been incorporated into NCCN protocols.

Why M6 Cyber knife is preferred?

The Cyber knife system is a method of delivering radiotherapy, with the intention of targeting treatment more accurately than standard radiotherapy. It consists of two main components: Linac, which produces the radiation, and a robotic arm which allows the energy to be directed at any part of the body from any direction.

CyberKnife radiation surgery is the most advanced, non invasive radiation therapy tool available to treat cancerous as well as non cancerous diseases with the help of precise beams of high-dose radiation. It is a no pain and a no risk day-care treatment wherein patients are discharged as soon as the session gets over and therefore, no hospitalisation is required. The treatment uses a sophisticated image guidance system to beam high doses of radiation directly to your tumor.

The CyberKnife radiation therapy works the best for tumors that are upto 3cm in size. Cyberknife radio surgery is a very powerful and precise radiation technique, for patients with early stage primary, medically inoperable lung cancer. The treatment is safe to administer and also offers a new option in patients with recurrent disease or a single metastatic disease in the lung.

The Cyberknife-M6 device is uniquely designed to deliver an accurate and exact radiation dose to a moving cancer target in the chest, while preserving the maximum possible adjacent tissue, making it an ideal device to treat lung cancer patients. The CyberKnife-M6 device is the only radio surgery or radiotherapy device that tracks and treats a moving cancer throughout the entire breathing cycle. This enables an even smaller margin of normal tissue around the cancer to be treated, increasing the safety of treatment.

(The writer is senior consultant radiation oncology)