Results of a new study suggest that breast cancer–related lymphedema is strongly associated with multimodality treatment, including chemotherapy, and not axillary node surgery alone.
A new study suggests that breast cancer–related lymphedema is strongly associated with multimodality treatment, including chemotherapy, and not axillary node surgery alone. Results presented at the 2017 American Society of Breast Surgeons Annual Meeting showed that there may be several risk factors that cumulatively increased the likelihood of lymphedema in women with breast cancer, including chemotherapy, more advanced disease, and above normal body weight.
“We must recognize that today, breast cancer is no longer a disease treated primarily through surgery, and many therapies impact the risk of this chronic condition,” said researcher Judy Boughey, MD, FACS, of the department of surgery at Mayo Clinic, in a press release. “Risk factors appeared to be cumulative, affecting women in a step-like fashion.”
Patient who undergo treatment for breast cancer are known to be at risk for upper extremity lymphedema, Boughey explained. The incidence of lymphedema can vary from 3% to 65% based on treatments undergone, mode of diagnosis of lymphedema, and time of follow-up.
With this study, Boughey and colleagues took a population-based sample of all incident breast cancer cases diagnosed in Olmsted County, Minnesota, from 1990–2010 (n = 1,794). The time to breast cancer–related lymphedema (BCRL) was calculated from time of surgery to date of diagnosis.
The study included patients with stage 0–III disease. The median follow-up was 10 years. Most patients in the study underwent axillary staging surgery: 44% had axillary lymph node dissection and 40% had sentinel lymph node biopsy only. Sixteen percent of patients had no axillary surgery.
There were 209 BCRL events observed during the study period and the majority (78%) occurred within 5 years of the surgery. The cumulative incidence of BCRL was 6.9% at 2 years, 9.1% at 5 years, and 11.4% at 10 years. All patients who developed lymphedema within 5 years had undergone some form of axillary surgery. No lymphedema was diagnosed among the 282 patients who did not undergo axillary surgery.
Looking at the incidence of BCRL lymphedema by surgery type, the study showed no difference in the rate of lymphedema among patients who underwent mastectomy compared with breast conserving surgery.
There was a difference in the incidence of BCRL among patients who underwent sentinel lymph node biopsy compared with axillary lymph node dissection (5.3% vs 15.9%). However, among the 453 patients treated with surgery alone, there was no difference in the rate of BCRL between patients who underwent sentinel vs axillary lymph node dissection (4.1% vs 3.5%).
When looking at patient characteristics, the researchers found that lymphedema was associated with stage II or III disease because patients typically were treated with radiation and/or chemotherapy. Lymphedema risk was also increased with higher body mass index.
“Clearly, for a realistic perspective on lymphedema risk, women should talk not only to their surgeons but also to their oncologists and radiation oncologists and take into account the full multidisciplinary treatment that they are undertaking,” Boughey said.