Impact of retrograde anastomosis during supermicrosurgical lymphaticovenous anastomosis for cancer-related lower limb lymphedema: A retrospective cohort propensity-score-matched outcome analysis

In addition to antegrade anastomosis, retrograde anastomosis has been thought to offer further improvements after lymphaticovenous anastomosis (LVA) by bypassing the retrograde lymphatic flow. However, this concept has yet to be validated. The aim of this study was to determine the impacts on outcomes of performing both retrograde and antegrade anastomosis, as compared to antegrade-only anastomosis for treating lower limb lymphedema.This was a retrospective cohort propensity score-matched study. Eighty-seven patients with gynecologic cancer-related lower limb lymphedema were enrolled, including 58 patients who had received both antegrade and retrograde anastomoses (Group I) and 29 patients who had received antegrade-only anastomoses (Group II) as the control group. LVA was the primary treatment. Patients who had previous LVA, liposuction, or excisional therapy were excluded. Patient characteristics, intraoperative findings, and functional parameters including the ratio of indocyanine green-enhanced and flow-positive lymphatic vessels were recorded. Magnetic resonance volumetry was used for outcome assessments. The primary endpoint was the volume change at 6 months after LVA.After matching, a total of 26 patients have remained in each group. All parameters were matched except that Group I still had significantly more median LVA performed compared to Group II (8 [IQR: 5.3-10.0] vs. 5.5 [4.3-6.0], p = 0.001, respectively). Group II showed more post-LVA improvements at six-month and one-year follow-up compared to Group I but without statistically significant differences.The use of supplementary retrograde anastomoses is discouraged since it may lead to inferior post-LVA outcome compared to antegrade-only anastomoses.