The effect of combined risk factors on breast cancer-related lymphedema: a study using decision trees

Background The effect of combined risk factors on breast cancer-related lymphedema (BCRL) development has not yet been investigated. This study aimed to determine the combination of risk factors associated with BCRL development in patients who underwent breast cancer resection, including axillary lymph node dissection (ALND). Methods The participants included 129 women who were diagnosed with early-stage breast cancer and underwent breast cancer resection in this retrospective observational study. We performed a decision tree analysis to detect the combination of risk factors associated with BCRL development using age, body mass index (BMI), surgical side, mastectomy, the extent of ALND, and adjuvant therapy (chemotherapy, hormone therapy, and radiation therapy). Results Of the 129 participants, 11 (8.5%) developed BCRL. Postoperative chemotherapy was the optimal variable selected to classify patients who developed BCRL and those who did not. In participants with postoperative chemotherapy, the extent of ALND was selected as the second layer of the decision tree. When ALND was at level 3, BMI was selected as the third layer. We found that BCRL incidence was 44.4% in individuals with a BMI of 23.0 or higher. Conclusions The combination of postoperative chemotherapy, level 3 ALND, and BMI of 23.0 or higher may further increase the risk of developing BCRL. The decision tree model will enable the identification of patients with a high risk of developing BCRL, and thus, preventive intervention, careful monitoring, and early treatment will be possible.