Patients who underwent surveillance with bioimpedance spectroscopy were less likely to develop chronic breast cancer–related lymphedema compared with patients who were assessed with tape measure.
Bioimpedance spectroscopy (BIS) is a more accurate method of identifying which breast cancer survivors will need compression intervention compared with tape measurement (TM) to prevent chronic lymphedema, according to findings from a study published in Lymphatic Research and Biology.1
Specifically, results from the PREVENT study (NCT02167659) showed that among patients who received compression intervention after early lymphedema detection, only 7.9% of patients who were assessed through BIS developed chronic lymphedema. In comparison, 19.2% of patients who were assessed using TM developed this chronic disease. These statistically significant results (P = .016) may translate into an absolute reduction of 11.3%, as well as a relative reduction of 59% in lymphedema progression at 3 years, according to the study authors.
"This timely knowledge gives clinicians the information they need to begin early intervention on their patients at a stage when it's possible to keep the lymphedema from advancing," principal investigator Sheila H. Ridner, PhD, RN, FAAN, research professor at Vanderbilt University School of Nursing, said in a press release.2 "These findings provide all clinicians addressing lymphedema in breast cancer patients with clear scientific data regarding the optimal measurement and sound evidence to switch from using tape measurements."
Chronic breast cancer–related lymphedema (C-BCRL) has become more prominent as the rate of breast cancer survivorship has continued to rise. As such, the number of patients affected by pain, infections, limited arm function, reduced quality of life, and very expensive therapies because of C-BCRL has also grown in recent years.
Currently, 5% of patients who undergo breast conserving surgery with SLNB alone experience C-BCRL, as well as more than than 50% of patients who undergo axillary lymph node dissection (ALND), regional node irradiation (RNI), and/or taxane-based chemotherapy. These statistics underscore the value of proper BCRL identification in breast cancer survivors, the authors explained. However, early-stage C-BCRL identification can be challenging.
Although subclinical disease and extracellular fluid occurs before changes becomes visible, C-BCRL diagnoses do not typically occur until a visible change or symptom has become apparent. Researchers therefore decided to use bioimpedance spectroscopy (BIS) to identify early-stage C-BCRL (defined as ≥10% arm volume change from baseline requiring CDP) in survivors, as this diagnostic tool can recognize extracellular fluid change and has been found to improve patient outcomes when combined with short-course compression therapy.
The stratified, randomized, international trial included patients with recent breast cancer diagnoses who were undergoing either mastectomy/partial mastectomy, axillary treatment (dissection, sentinel lymph node biopsy [SLNB] >6 nodes or radiation), radiation therapy, or taxane-based therapy. Exclusion criteria included history of breast cancer; neoadjuvant chemotherapy; and previous radiation on the breast, chest wall, or axilla.
Participants were randomized 1:1 following a post-surgery eligibility reassessment and underwent prospective surveillance via either BIS or TM. If surveillance detected S-BCRL, patients were to wear a class 2 (23-32 mmHg, medi flat knit custom or Harmony® circular knit) compression sleeve and gauntlet for 12 hours/day for 4 weeks.
Patients were assessed between June 24, 2014, and September 11, 2018. In total, 442 evaluable patients were enrolled in the BIS cohort and 437 evaluable patients were enrolled in the TM cohort. The median follow-up was 32.9 months.
Presurgical measurements were collected at baseline for both the BIS or TM cohorts and collected again at 3, 6, 12, 18, 24, and 36 months and again following compression intervention. Some sites also conducted a 15- and 21-month follow-up as well.
The BIS evaluation was conducted via L-Dex®U400 and TM evaluation was conflicted using Gulick II tape. The patients’ arms were measure twice at 10-cm increments starting at the wrist and continuing up to 50 cm above the wrist. A truncated cone formula was used to automatically calculate arm volume.
Ultimately, the number patients whose disease progressed following compression intervention was lower in the BIS group than the TM group (7.9%, n = 7 vs 19.2%; n = 23, relative risk, 0.41; 95% CI, 0.13-0.81; absolute reduction 11.3%; 95% CI, 2.3-20.3; P = .016).
"The results of this study provide clarity for patients and clinicians regarding breast cancer–related lymphedema (BCRL) screening and early intervention," co-investigator Chirag Shah, MD, director of Breast Radiation Oncology and director of Clinical Research in the Department of Radiation Oncology at Cleveland Clinic, said.
"The primary outcome demonstrated the benefit of prospective monitoring with L-Dex coupled with early intervention in reducing rates of chronic lymphedema, which is important clinically due to the impact of chronic BCRL on patients' quality of life,” he added. “One of the most significant components of the results was the risk-adjusted analysis. When looking at key risk factors for BCRL, including body weight, stage of cancer, type of cancer surgery, lymph node dissection, chemotherapy, and radiation, the benefit of using L-Dex monitoring was consistent and showed the utility of L-Dex across a large group of [patients with breast cancer].”