Radiation for Lung Cancer

In this video we review two types of radiation therapy for lung cancer, SBRT and EBRT.  We also review the common side effects of radiation  for peripherally located and centrally located tumors.

Read the full video transcript below:

For some patients with lung cancer, surgery is not the best treatment option. 

The most common reasons to avoid surgery for lung cancer are the disease is too advanced to remove surgically, or the patient is simply too sick and could not withstand a surgery. In these cases, radiation therapy, a noninvasive x-ray treatment, is a good alternative to surgery and can provide curative treatment options for patients who cannot have surgery. 

For patients with a relatively small lung cancer with no lymph nodes involved. A special technique called stereotactic body radiation therapy or SBRT for short is a good option, with a high chance of cure and a low chance of side effects. With SBRT, a very focused radiation beam is applied to the tumor with very little radiation dose going to the surrounding tissues. 

Unlike surgery where the tumor is physically removed, with SBRT, the tumor slowly transforms and dies and basically turns into a scar. SBRT is an outpatient procedure typically delivered over 1 to 5 treatment days. Patients with lung cancers that has spread to lymph nodes in the middle part of the chest require larger field radiation called external beam radiation therapy, or EBRT for short. With this, the radiation beam is directed not just at the primary tumor at the lung, but also at the involved lymph nodes and some of the surrounding tissues that may be at risk for harboring small microscopic amounts of tumor. 

The side effects of radiation therapy for lung cancer are determined by which normal organs are adjacent to the tumor. In the case of SBRT treatment, near the periphery of the lung, the organ most at risk is the lung itself. 

There is some region of surrounding normal lung right around the tumor that will get a relatively high dose of radiation therapy. Sometimes there are adjacent ribs, which will also get a relatively high dose of radiation. Therefore, the main risks of SBRT in this location are lung inflammation and rib injury. 

When radiation therapy is delivered to the middle part of the chest, the risks are very different. In this case, the central part of the lung is at risk for inflammation and long term injury. 

The windpipe or trachea and the large airways called the bronchi are also at risk of injury. 

The esophagus moves food from the mouth down to the stomach and  when it is inside the radiation field that can cause difficulty or pain swallowing. Sometimes the heart is either adjacent to or inside the radiation field, which can increase the risk of a long term cardiac injury. 

The spinal cord sits behind all of the contents of the chest. Great care and attention is paid to the dose to the spinal cord to avoid an injury. So spinal cord injuries from radiation therapy is extremely uncommon with modern treatment. 

This is not medical advice. Talk to your doctor before making any medical decisions.