A Prospective Validation Study of Bioimpedance with Volume Displacement in Early-Stage Breast Cancer Patients at Risk for Lymphedema

Abstract

BACKGROUND Although volume displacement (VD) is considered the gold standard for diagnosing breast cancer (BC)-related lymphedema, it is inconvenient. We compared bioimpedance (L-Dex) and VD measurements in a prospective cohort of BC patients at risk for lymphedema. METHODS Between 2010–2014, 223 BC patients were enrolled. Following exclusions (n=37), 186 received baseline VD and L-Dex; follow-up measurements were performed at 3–6 month intervals for 3 years. At each visit, patients fit into one of three categories: normal (normal VD and L-Dex); abnormal L-Dex (L-Dex>10 or increase in 10 from baseline and normal VD); or lymphedema (relative arm volume difference of >10% by VD +/− abnormal L-Dex). Change in L-Dex was plotted against change in VD; correlation was assessed using Pearson correlation. RESULTS At a median follow-up of 18.2mos, 152 patients were normal; 25 had an abnormal L-Dex; and 9 developed lymphedema without a prior L-Dex abnormality. Of 25 abnormal L-Dex patients, 4 progressed to lymphedema for a total of 13 patients with lymphedema. Evaluating all time points, 186 patients had 829 follow-up measurements. Sensitivity and specificity of L-Dex compared to VD were 75% and 93%, respectively. There was no correlation between change in VD and change in L-Dex at 3mos (R=0.31) or 6mos (R=0.21). CONCLUSIONS VD and bioimpedance demonstrated poor correlation with inconsistent overlap of measurements considered abnormal. Of patients with an abnormal L-Dex, few progressed to lymphedema; most with lymphedema did not have a prior L-Dex abnormality. Further studies are needed to understand the clinical significance of bioimpedance.

Body Composition with Dual‐Energy X‐Ray Absorptiometry and Bioelectrical Impedance Analysis in Breast Cancer Survivors

“…BCS have a 2‐fold to 3‐fold higher prevalence of obesity than survivors of other cancers (ie, kidney, pancreas, and thyroid cancer), and it is estimated that obesity will cause >500,000 additional cases of cancer in the United States by 2030 . Body composition in BCS has been measured by a variety of methods, including dual‐energy x‐ray absorptiometry (DXA), computed tomography, bioelectrical impedance analysis (BIA), skinfolds, and magnetic resonance imaging to describe and lower excessive body components (ie, central adiposity, body fat mass) known to be related to increased risk of cancer mortality and recurrence in BCS. Each procedure has distinct advantages and disadvantages, namely, accuracy, feasibility, cost, and availability; however, some procedures may be limited for research investigations with BCS due to availability and cost, and may contribute to unreliable results of clinical studies.…”

A comprehensive review of bioimpedance spectroscopy as a diagnostic tool for the detection and measurement of breast cancer-related lymphedema

“…Several methods have been used in the past to screen for lymphedema. The current “gold standard” is water displacement . A study comparing bioimpedance to volume displacement cited a >1% error rate for the water displacement technique.…”

“…The cylinder is filled with water up to a determined mark on the participants arm some distance from the olecranon process. The volume is then recorded before and after the arm is removed and the difference is calculated . The generally accepted diagnostic cutoff for defining lymphedema by volume displacement is a relative volume increase of ≥10% or ≥200 ml when compared to either the contralateral arm or a baseline measurement for the affected arm .…”

Efficacy of Ultrasound and Shear Wave Elastography for the Diagnosis of Breast Cancer–Related Lymphedema

“…First, the latent lymphedema was diagnosed by BIS, and the manufacturer's cutoff value of +10 or –10 was used for a positive examination result. The use of the documented sensitivity and specificity rates for BIS at the various cutoff points may have led to underestimation or overestimation of the latent cases . Second, the study participants, who were all patients with a history of breast cancer, were at risk for developing lymphedema.…”

“…The use of the documented sensitivity and specificity rates for BIS at the various cutoff points may have led to underestimation or overestimation of the latent cases. 30,31 Second, the study participants, who were all patients with a history of breast cancer, were at risk for developing lymphedema. Finally, no preoperative measurements of these patients were available for comparison.…”