Background: Breast cancer-related lymphedema (BCRL) is a disabling and frequently occurring condition after treatment for breast cancer. Studying lymph anatomy by means of indocyanine green (ICG) lymphography is a promising tool to help better understand BCRL. The aim of this study is to investigate the relation between ICG lymphography characteristics and the risk of developing BCRL. Methods and Results: Patients scheduled for breast surgery with either unilateral axillary lymph node dissection or sentinel lymph node biopsy between November 2017 and May 2019 were included. Patients were assessed at baseline and up to 36 months postsurgery. BCRL was defined as an increase of ≥5% relative arm volume difference compared with the presurgical difference. In total, 128 patients were included. During 36 months of follow-up, 45 patients (35.2%) developed BCRL. The number of lymph vessels before surgery was not a statistically significant risk factor for developing BCRL (p = 0.8485). However, an increase in the number of lymph vessels compared with baseline was a significant protective factor for developing BCRL (odds ratio = 0.8). An increase of one lymph vessel corresponds to a 19% relative risk reduction of developing BCRL. The presence of lymph nodes at baseline and the change in the presence of lymph nodes compared with baseline were no predictors for the development of BCRL (p = 0.0986 and p = 0.8910, respectively). Conclusions: An increase in the number of lymph vessels visualized by ICG lymphography compared with baseline is a protective factor for developing BCRL. Therapies with the ability to increase the number of lymph vessels can thus possibly decrease the risk of developing BCRL.
Keywords: ICG lymphography; breast neoplasms; lymphedema; near-infrared fluorescence imaging.