Painful swelling of the arm or shoulder area following treatment for breast cancer - a condition called lymphedema - is more common in women who are overweight or obese than in women of normal weight, researchers have found.

Lymphedema is a common, chronic condition that often develops after breast surgery involving the removal or damage to the lymph nodes in the armpit. Radiation therapy, post-operative infection and age have also been implicated. The condition occurs when excess fluid accumulates, leading to swelling, rash, redness and blistering that causes tenderness, numbness, or aching in the arm, chest wall and breast.

In their study of 193 breast cancer survivors, Dr. Jane M. Armer and colleagues at the University of Missouri-Columbia found that the risk of lymphedema was 40 to 60 percent higher in women who are overweight or obese compared to normal-weight women.

The risk of lymphedema is especially high in overweight or obese women who have cancer treatment to the dominant side or experience post-operation swelling, the researchers report. Post-operative swelling significantly increased the risk of lymphedema regardless of a woman’s body weight.

Based on their analysis, roughly two thirds of breast cancer survivors are at risk of developing lymphedema within 30 months after surgery, Armer and colleagues report in the current issue of the Journal of Lymphoedema.

“Diagnosing post-breast cancer lymphedema can be difficult,” Armer noted. She recommends increased health education for both breast cancer survivors and health care providers.

“Lymphedema has a profound impact on health and well-being, but often goes undiagnosed and untreated by physicians and patients,” she said.

In a previous study, Armer and colleagues found that many women who experience lymphedema after breast cancer treatment suffer in silence. Others don’t follow the treatment advice of their doctor or use “alternative” treatments, which they may not discuss with their doctors.

SOURCE: Journal of Lymphoedema, 2008.