Risk factors and prediction model for persistent breast-cancer-related lymphedema: a 5-year cohort study

Breast-cancer-related lymphedema (BCRL) can be a transient or persistent condition. The aims of this study were to (1) identify and weigh the risk factors for persistent lymphedema (PLE) among all patients with BCRL and (2) establish a prediction model for the occurrence of PLE.

A cohort of 342 patients with BCRL with a median follow-up of 5 years after the onset of swelling was analyzed. PLE was defined as a hardening of the subcutaneous tissue, the persistence of the circumferential difference (CD) between arms, or a flare-up of swelling during follow-up. Multiple logistic regression was used to identify risk factors for PLE, including tumors, treatments, and patient-related factors. The prediction accuracy of the model was assessed using the area under the receiver operating characteristic curve (AUC).

Of the 342 patients with BCRL, 229 (67%) had PLE. Multiple logistic regression analysis revealed that the number of lymph node metastases (p = 0.012), the maximal CD between arms at the first occurrence of swelling (p < 0.001), and the largest difference during follow-up (p < 0.001) were significant predictors for PLE. The corresponding AUC was 0.908. Although inclusion of body weight gains (p = 0.008) and maximal CD at the latest follow-up (p = 0.002) increased the analytical accuracy (AUC = 0.920), the resulting AUC values (p = 0.113) were not significantly different.

BCRL is persistent in two thirds of patients. Patients with more lymph node metastases, weight gain, and larger CD since the onset of swelling and during follow-up have an increased likelihood of developing PLE.