Risk Factors for the Development of Clinical and Subclinical Lymphedema Detected by Bioimpedance Spectroscopy

Breast cancer-related lymphedema can significantly compromise quality of life. Bioimpedance spectroscopy (BIS) measures extracellular fluid in lymphedema. The purpose of this study was to determine the incidence of BIS-detected lymphedema using the L-Dex and identify risk factors associated with a positive score. We performed a retrospective review of our institutional database to identify patients who underwent L-Dex U400 measurements. Patients with a score of > 10 L-Dex units or with an increase of > 10 units from baseline had a positive score. Clinical lymphedema was determined by documentation in the chart at the time of positive measurement. Otherwise, patients were considered to have subclinical lymphedema. Fifty-three patients met study criteria. Thirty patients (56.6%) underwent mastectomy, 22 (41.5%) axillary lymph node dissection (ALND), and 33 (62.3%) received radiation (RT). Twelve patients (22.6%) had a positive score. There were no differences in age, race, laterality, breast surgery, T stage, N stage, chemotherapy, or RT fields (none, breast only, breast with LNs) in patients with a positive score. ALND was more common (66.7% vs. 34.2%, P= .04). BMI > 30 approached significance (58.3% vs. 29.3%, P= .06). Seven patients had subclinical lymphedema. No differences were identified comparing patients with subclinical lymphedema to those with negative scores. All 5 patients with clinical lymphedema underwent ALND and received nodal RT. The combination of ALND and regional nodal RT is strongly associated with development of clinical lymphedema. It is difficult to identify patients at risk for subclinical BIS-detected lymphedema. The treatment of breast cancer can cause lymphedema, which greatly impact patients’ quality of life. Earlier treatment of lymphedema is more effective, but preclinical lymphedema is difficult to detect. We used a new tool, bioimpedance spectroscopy, to detect preclinical lymphedema. This tool may allow physicians to intervene on lymphedema early, before patients develop irreversible symptoms.