Background: This study compared rates of progression to chronic breast cancer-related lymphedema (defined as ≥ 10% arm volume change from baseline requiring complex decongestive physiotherapy [CDP]) following an intervention for subclinical lymphedema (S-BCRL) triggered by bioimpedance spectroscopy (BIS) or by tape measurement (TM). Methods and Results: This stratified, randomized, international trial enrolled new breast cancer patients undergoing: mastectomy/partial mastectomy, axillary treatment (dissection, sentinel lymph node biopsy [SLNB] >6 nodes or radiation), radiation therapy (chest wall/breast, supraclavicular fossa), or taxane-based chemotherapy. Following postsurgery eligibility reassessment, centralized, 1:1 randomization to prospective surveillance by BIS or TM occurred. S-BCRL detection triggered a 4-week, 12-hour per day, compression sleeve, and gauntlet intervention. The primary outcome (n = 209), rates of postintervention progression to CDP, was assessed over 3 years. Between June 24, 2014 and September 11, 2018, 1200 patients were enrolled, 963 randomized (BIS n = 482; TM n = 481) and 879 analyzed (BIS n = 442; TM n = 437). Median follow-up was 32.9 months (interquartile range = 22, 35). BIS patients triggered an intervention at a lower rate than TM patients (20.1%, n = 89 vs. 27.5%, n = 120, p = 0.011). Median months to trigger were longer with BIS than TM (9.7; 95% confidence interval [CI], 8.2-12.6 vs. 3.9; 95% CI, 2.8-4.5, p = 0.001). Overall, 14.4% (n = 30) progressed post-intervention, with reduced likelihood for BIS patients than TM patients (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 = 0.016). Conclusions: Compared to TM, BIS provides a more precise identification of patients likely to benefit from an early compression intervention. Clinical Trial Registration number: NCT02167659.
Keywords: bioimpedance spectroscopy; breast cancer; lymphedema; prevention; tape measure.