By Marilynn Larkin
Source: Reuters - 25/7/2019
Increasing body mass index and longer neoadjuvant chemotherapy (NAC) are associated with a higher risk of lymphedema in women who undergo axillary lymph node dissection, researchers say.
"All cancer survivors who have lymph node removal or radiation should be followed in surveillance for early signs of lymphedema and those with higher BMI undergoing both axillary lymph node dissection and a longer course of neoadjuvant warrant enhanced surveillance by the oncology team," Dr. Jane Armer of the University of Missouri in Columbia told Reuters Health by email.
"Benefits to the survivors of nutritionally-sound weight management include not only lymphedema risk reduction," she said, "but also potential secondary outcomes, including positive impact on breast cancer recurrence, self-care, and overall health."
Dr. Armer and colleagues analyzed data on women with cT0-T4N1-2M0 breast cancer with axillary nodal metastasis at diagnosis who were enrolled in the American College of Surgeons Oncology Group Z1071 (Alliance for Clinical Trials in Oncology) trial.
All participants in that trial received NAC, breast surgery, and axillary lymph node dissection. In the trial's lymphedema substudy, 486 patients (mean age, 50) underwent arm measurements and symptom assessment after NAC completion and at six-month intervals for up to three years postoperatively.
Factors associated with lymphedema were defined as self-reported arm heaviness or swelling (lymphedema symptoms) or an arm volume increase of 10% or more (V10) or 20% or more (V20). As reported online July 17 in JAMA Surgery, at three years, the cumulative lymphedema incidence was 37.8% for lymphedema symptoms, 58.4% for V10, and 36.9% for V20.
Increasing body mass index (hazard ratio, 1.04) and NAC for 144 days or longer (HR, 1.48) were associated with lymphedema symptoms. Further, the V20 incidence was higher among patients who received NAC for 144 days or longer (HR, 1.79).
The V10 incidence was highest in patients who had at least 30 nodes removed (HR, 1.70) and increased with number of positive nodes (HR, 1.03).
On multivariable analysis, obesity was significantly associated with lymphedema symptoms (HR, 1.03), and NAC length was significantly associated with V20 (HR, 1.74).
Dr. John Vetto of Oregon Health and Science University in Portland, author of a related editorial, commented by email, "Lymphedema after breast cancer treatment is multifactorial and everyone has a role in reducing it."
"Medical oncologists can be aware that certain chemo regimens and schedules may cause more lymphedema than others," he told Reuters Health. "Radiation oncologists may be able to modify radiation techniques to reduce the risk."
"Surgeons can use reverse mapping techniques and knowledge of nodal anatomy to reduce removal of nodes that mostly drain the arm," he noted. "They should also be aware of ongoing clinical trials that give neoadjuvant chemo patients the option of sentinel node biopsy only."
"Patients should be told openly and honestly - without blame or judgment - that achieving and maintaining a healthy weight can reduce the risk," Dr. Vetto concluded.
JAMA Surg 2019.