The use of bioimpedance spectroscopy to monitor response to treatment interventions with breast cancer-related lymphedema.

Abstract

138 Background: Currently, limited tools are available to assess response to therapy in patients with breast cancer related lymphedema (BCRL). The purpose of this study was to perform an exploratory analysis to determine if, in clinical settings, bioimpedance spectroscopy (BIS) can detect changes in extracellular fluid volume in response to treatment of BCRL. Methods: Three centers that had experience with BIS (L-Dex U400, ImpediMed Limited, Brisbane, Australia) provided retrospective data on 50 patients with breast cancer who were evaluated with BIS at baseline and following loco-regional procedures. Patients had a pre-surgical L-Dex measurement as well as at least 2 post-surgical measurements (before and after BCRL intervention). Decisions regarding intervention were made by physicians with no L-Dex score cut-off utilized. An analysis was performed comparing changes in L-Dex scores for those patients undergoing treatment for BCRL (n=13) versus those not undergoing intervention (n=37). A second analysis was also performed on all patients with elevated L-Dex scores compared to baseline prior to intervention (n=32). Results: The mean age was 54 years old. Fifty four percent of patients underwent SLN biopsy with a mean of 7.9 nodes removed. The mean change in L-Dex score from baseline (pre-treatment) to the first post-surgical L-Dex score measurement was 3.3 +/- 6.8. When comparing the cohort treated for BCRL to those not treated, L-Dex scores were significantly reduced (-4.3 v. 0.1, p=0.005) following intervention. For the subset of patients with elevated L-Dex scores post-surgery, the change in L-Dex score following BCRL intervention was significantly reduced (-5.8 v. 0.1, p=0.001) compared with those observed. Conclusions: These results confirm that BIS can detect increases in L-Dex scores following breast surgery and can also detect reductions in L-Dex scores following intervention for early onset lymphedema. These results demonstrate that BIS has significant clinical utility as it can be used to monitor patients with early BCRL who undergo intervention and to follow these patients (through serial measurements) to document their short and long-term response to these treatments.