Prolongation of Postoperative Drainage Time in Indocyanine Green Lymphography as a Potential Marker for Lymphedema Development—A Prospective Pilot Study

Objectives: Lymphedema (LE) is a debilitating complication in breast cancer patients, typically identified through clinical symptoms and volume-based diagnostics. As early diagnosis is crucial for favorable outcomes of microsurgical procedures, a more sensitive tool for LE assessment is required. The primary aim of this study was to evaluate whether a prolongation in postoperative indocyanine (ICG) lymphography drainage time, relative to preoperative baseline values, serves as a predictor of future LE development. Methods: A total of 41 women undergoing axillary lymph node dissection received ICG lymphography preoperatively and four weeks postoperatively. Drainage time (the duration for ICG to reach the axilla) was recorded. Clinical LE was defined as a >10% limb volume difference 12 months post-surgery, while subjective LE (sLE) was assessed via the Lymphedema Life Impact Score. Results: LE developed in 19.5% of patients. Patients who developed LE exhibited significantly higher mean drainage prolongation compared to those who did not (335 s vs. 40 s; p = 0.004). ROC analysis identified an optimal threshold of 119 s for predicting LE, yielding 100% sensitivity and 84.85% specificity (AUC = 0.96). sLE was reported by 48.8% of patients. Their drainage prolongation was significantly greater than in the sLE group (188 s vs. 13 s; p = 0.03). Conclusions: Preliminary findings suggest postoperative prolongation of ICG drainage time may serve as a potential predictor of future LE. In our cohort, a 119 s delay at four weeks post-operation was associated with LE at 12 months. While these results are promising, further research in larger, more diverse populations is required to validate these thresholds for clinical utility.