According to the American Cancer Society, radiation therapy has been used to treat breast cancer for almost a century. It is now used to treat all stages of breast cancer, ranging from early stage invasive disease and ducal carcinom in situ (DCIS) to late-stage cancers that require mastectomies. Radiation therapy for breast cancer has several long-term adverse effects, but their incidence is generally low.
Arm Edema
According to the book "Cancer of the Breast," moderate to severe arm edema (swelling) can occur in 3 to 10 percent cases of breast radiation therapy alone. If radiation therapy is also used to treat affected regional lymph nodes, then the risk of developing arm edema is increased to 25 to 30 percent.
Rib Fracture
According to BreastCancer.Org, radiation therapy might weaken the ribs of the side that received treatment and increase the risk of rib fracture. This is a rare event, and occurs at a median of one year after radiation.
Heart and Lung Damages
Radiation of left-sided breast cancer might sometimes include portions of the heart. This potentially increases the risk of having heart attack, according to "Cancer of the Breast."
Radiation therapy for breast cancer also causes lung inflammation (pneumonitis). This occurs in fewer than 2 percent of patients who received treatment, according to "Cancer of the Breast." The symptoms of penumonitis often begins two to three months after completion of treatment.
Other Cancers
Patients undergoing radiation therapy for breast cancer are at higher risk of developing other cancers, according to the Amercan Cancer Society. Most of these secondary cancers occur five to 10 years after the initial treatment.
References
- American Cancer Society: Breast Cancer Radiation Therapy
- BreastCancer.org
- "Cancer of the Breast;" Donegan, W., Spratt, J.; 2002
