Multi-institutional analysis of bioimpedance spectroscopy in the early detection of breast cancer related lymphedema

Background: The purpose of this study was to evaluate bioelectrical impedance spectroscopy's (BIS) ability to detect and monitor extracellular fluid accumulation of the upper limb as it relates to the extent of loco-regional therapy. Methods: A total of 125 patients with breast cancer from 4 clinical practices were evaluated with BIS at baseline and following loco-regional procedures. In order to assess the ability of BIS to detect subclinical changes by treatment modality, the change in L-Dex score from baseline to measurements taken within 180 days following surgery were calculated. Results: Mean age was 55 years with 68 patients (54.4%) undergoing sentinel lymph node (SLN) sampling while 57 (45.6%) underwent an axillary dissection (ALND). Sixty-five patients (52%) underwent radiation therapy (RT). Patients receiving RT had a significantly increased change in L-Dex score (0.8 v.-2.5, p=0.03) compared with those patients not receiving RT. For all patients, ALND was associated with a significantly increased change in L-Dex score (5.0 v. 0.3, p=0.003) compared with SLN. When stratifying by the number of nodes removed, a statistically significant increase in the change in L-Dex score was noted (0.4 v. 0.4 v. 4.3 v. 6.4, p=0.04) for 0-3, 4-6, 7-10 and greater than 10 lymph nodes removed. Conclusions: In this limited analysis, L-Dex scores paralleled the extent of axillary sampling and the addition of radiation therapy; these results demonstrate that BIS can be used to monitor patients for the early onset of edema as differences emerged within 180 days of surgery.