The use of bioelectrical impedance spectroscopy (BIS) to detect subclinical changes potentially associated with the development of breast cancer-related lymphedema.

Abstract

89 Background: The purpose of the 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 locoregional therapy for patients with breast cancer. Methods: A total of 125 patients from 4 clinical practices, with newly diagnosed breast cancer were evaluated at baseline and following locoregional procedures that could potentially affect fluid accumulation in the arm and signal the possible development of early lymphedema. In order to assess the ability of BIS to detect sub-clinical changes by treatment modality, the change in L-Dex score from baseline to measurements taken within 180 days following surgery were calculated. Results: Fifty-one patients (40.8%) underwent lumpectomy and 74 (59.2%) mastectomy; 68 patients (54.4%) underwent sentinel lymph node (SLN) sampling. Sixty-five patients underwent radiation therapy (RT) with RT patients being more likely to have undergone lumpectomy (66.2% v. 3.2%, p<0.001) and axillary dissection (41.5% v. 19.4%, p=0.04) compared with patients not receiving RT. However, no difference in the mean number of nodes sampled (7.7 v. 5.4, p=0.14) was noted for patients receiving RT compared with those not receiving 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 suggest that BIS can be used to monitor patients for the early onset of edema as differences emerged within 180 days of surgery.