Ultima Vez Modificado: 17 de febrero del 2008
Dear OncoLink "Ask The Experts,"
My husband has lung cancer; it was a tumor in an area of the lung that made surgery impossible. He had radiation treatments about six months ago and the tumor shrunk a lot. He has recently developed terrible problems with breathing. The doctors say it is radiation pneumonitis. He is on Prednisone and uses oxygen at home. He has to sleep in a recliner and has trouble sleeping. Are there any other treatments for this and will it ever go away?
Pinaki R. Dutta, MD, PhD, Resident in the Department of Radiation Oncology at the Hospital of the University of Pennsylvania, responds:
Although it is good to hear that the tumor decreased in size after the treatments, the issues of radiation-induced lung injury, or radiation
pneumonitis, is often a problem in patients like your husband. The symptoms your husband has are compatible with radiation pneumonitis, and it appears that he is on the right treatment.
Unfortunately, the cause is not entirely understood, as even areas of the lung that were not irradiated can also be affected by the process. However, the likelihood of developing the symptoms does increase with increasing amounts of irradiated lung tissue. Although we know that radiation pneumonitis is linked to elevated levels of cytokines ( inflammatory markers in the body), we still do not know how to always predict who will get it, nor how to always prevent it. Some risk factors are known. If your husband has a history of smoking, it would further increase his risk of radiation pneumonitis. Receiving chemotherapy during radiation can also increase the risk of developing this process.
After radiation (days to weeks), an inflammatory reactive process may lead to the development of thick secretions. These secretions may accumulate and be difficult to clear. The inflammation can basically develop into a condition called radiation pneumonitis, and can occur anywhere from 3-12 weeks following radiation. Eventually, there may be a resolution of the secretions and symptoms, or it can result in more long-term scarring, known as pulmonary fibrosis. This scarring may develop as early as 6 months following irradiation and can progress over years.
The symptoms of radiation pneumonitis usually consist of the following:
An early nonproductive cough; trouble with taking a deep breath; a low-grade fever, but can be more pronounced in severe cases; chest pain with breathing; malaise; and weight loss.
Because pneumonia may also have these symptoms, it is important to be evaluated by a physician to make the distinction, as a pneumonia is often treatable with antibiotics or other therapies.
In the treatment of radiation pneumonitis, the mainstay is oral steroid therapy that is titrated over several weeks. Prednisone (at least 60 mg/day) is generally given for two weeks, with a very slow taper over 3 to 12 weeks, or even longer. Pentoxifylline has also been used to prevent or decrease the progression to radiation-induced fibrosis.
Significant improvement in the symptoms that your husband feels may take weeks to months as the steroids are carefully adjusted. Unfortunately, it is hard to predict. Some investigators have reported anywhere from 3 to 18 months after radiation therapy for the symptoms to fully resolve. Some studies demonstrate that after 18 months, any further significant improvement is rare. Proper management with a pulmonologist and radiation oncologist who specializes in lung cancer would be advised.