For the treatment of lung cancer, radiation therapy can be used as either a local treatment aiming to cure the cancer or a treatment to alleviate the symptoms.
Lung cancers are divided into two main groups as follows:
- Non-small cell lung cancers,
- Small cell lung cancers.
The primary standard treatment for a local, non-small cell lung cancer is surgery, which is supplemented by radiation therapy if necessary. However, some patients with early stage lung cancer are not eligible for surgical treatment due to other diseases. For these patients, the alternative treatment is radiation therapy targeted with precise definition (the so-called stereotactic radiation therapy). The treatment is generally given in a few large single doses to the tumor area.
Around one-third of all non-small cell lung cancers are diagnosed as locally advanced malignancies and ineligible for surgery. For this patient group, the treatment currently regarded as the standard is radiation therapy and adjunct treatment with two cytostatics, given simultaneously over a period of six weeks.
Local, small cell lung cancer is treated with a combination of chemotherapy and radiation therapy.
In the treatment of advanced lung cancer, radiation therapy can often alleviate the symptoms regardless of the type of lung cancer at stake.
Radiation therapy for the lung area is often planned by means of high-quality computed tomography. This imaging is often enhanced by a radiocontrast agent. Alternatively, respiratory-gated computed tomography (4DCT) is performed to help define the motion of the treatment site and consider this when planning the radiation therapy.
With the current dose planning systems, the radiation doses to healthy tissues can be determined precisely. Thus, the drawbacks to healthy tissues and organs can be minimized.
Radiation Therapy Benefits and Drawbacks
Combination therapy (simultaneous chemotherapy and radiation therapy) for locally advanced non-small cell and small cell lung cancer has been found to be more effective than mere radiation therapy or therapies given alternately.
Generally, the immediate adverse effects of radiation therapy given for locally advanced lung cancer include fatigue and esophageal irritation. Any symptomatic lung inflammation, appearing two to three months after radiation therapy on average, is treated with cortisone and, if necessary, an antibiotic.
Fibrosis (i.e. fibrous connective tissue) may develop in the treatment area as a long-term adverse effect of radiation therapy given for lung cancer.
Duration of Radiation Therapy
Due to its short duration (generally three to five sessions), stereotactic therapy is comparatively easy on the patient. As for radiation therapy for locally advanced lung cancer, this generally takes around six weeks.
Palliative radiation therapy can be given either as a single treatment session or as a treatment period lasting one to two weeks, depending on the extent and location of the target area of the radiation therapy and the patient’s overall condition.