Radiation Therapy for Mesothelioma

Radiation treatment involves exposing a tumor or cancerous area to high levels of ionized energy particles.  These particles are usually electrons that detach from the energized particle.  In the case of cancerous tumors, radiation treatment damages the DNA of the cancer cell, destroying its ability to divide and ultimately destroying the cell itself.

Radiation therapy can cause damage in healthy cells as well, so delivering the treatment to the appropriate tissue mass is as much a science as calculating the medical effect of the treatment on the tumor.

For malignant mesothelioma radiation treatment is almost always used in conjunction with surgery or chemotherapy or both.  The technique may include multiple radiation beams aimed at the target tissue from several angle.  IN this fashion the normal tissue and organs that the beam must pass through receive much lower doses than the area where the beams meet.

Types of Radiation Delivery

• External radiation therapy is delivered by a beam from a machine near the patient.  It may be applied before surgery in an attempt to shrink the tumor.  It may be applied during surgery, in an effort to kill cancerous cells near the tumor site.  And it may also be used after surgery to reduce the possibility of recurrence.  A treatment program for mesothelioma cancer may last three to five weeks, with radiation applied up to five days a week.
  
• Internal radiation involves the placement of a tiny device containing radioactive material near the cancerous tissue or tumor.  It is not used commonly for mesothelioma, because the cancer is not necessarily concentrated in a single area.
  
• Systemic radiation or radioisotope therapy or is delivered orally or intravenously.  Often the radiation source is a form of iodine that has been treated to create the radioactive effect.
  
• In 2002 and 2003 the FDA approved two treatment substances (Zevalin and Bexxar) that join an antibody to a radionuclide, which is an atom with an unstable nucleus.  The antibodies are drawn to cancer cells, which are then destroyed by the radionuclide.  This is radio immunotherapy (RIT), a technique that has proven to minimize the damage to adjoining healthy cells.

Radiation Treatment Side Effects

• Radiation can cause harm to surfaces lined by epithelium, a type of tissue that includes our skin as well as the tissue on the inside of the mouth, the esophagus, the inside of the lungs, the gastro-intestinal tract and parts of the rectum.
  
  Soreness, redness, swelling and ulceration may occur on these surfaces.  Recovery to the external areas is relatively quick once the treatment is over.  Damage to the throat may make swallowing difficult; an affected GI system may result in diarrhea and nausea.
  
• Hair loss is a side effect of radiation treatment as well as with chemotherapy.  In the case of radiation the hair loss is more likely to be permanent, but is also likely to occur mainly in the area being treated.
  
• Dry mouth and dry eyes can be troubling long term side effects.  This dryness can extend to sweat glands in the treated area as well.
  
• Fatigue is a common complaint among radiation therapy patients.  It can continue for a period of weeks or months, depending on the patient's health and the intensity of treatment.
  
• Other side effects may occur only with the treatment of certain areas of the body.  Discuss the potential side effects - both near term and long term - with your physician, so you know what to expect.  The impact of side effects is usually lessened if you know what to expect.