Supplementary Material for: Efficacy of biomedical materials for the prevention of lymphocele after lymph node dissection for gynecological malignancies: A systematic review and meta-analysis of randomized controlled trials

Introduction:
Lymphocele is one of the complications after lymphadenectomy for female pelvic malignancies. In recent years, some studies indicated that the use of biomedical materials during surgery for gynecological malignancies may help to reduce the occurrence of lymphatic cysts, but results were inconsistent. The aim of the present study was to evaluate the correlation between the use of biomedical materials intraoperatively and formation of lymphocele after lymph node dissection in patients with gynecological malignancies.

Methods:
A systematic search of 4 electronic databases for articles published up to April 14, 2025 was performed. All randomized controlled clinical trials (RCTs) which reported lymphocele outcomes after application of biomedical materials for patients who underwent lymphadenectomy for gynecological malignancies, were finally included in the present meta-analysis. Statistical meta-analysis was performed using the RevMan 5.3 software.

Results:
Ten randomized controlled studies were finally included in the present study. A total of 879 patients (from 10 studies) with gynecological cancer who underwent pelvic lymph node dissection and/or para-aortic lymph node dissection were included in the meta-analysis. Pelvic lymphoceles were diagnosed in 249 patients (28.3%). The symptomatic lymphocele incidence proportion was 6.4% (47/731). The lymphocele incidence of biomedical material group was significant lower compared with control group (432 vs 447 cases, OR 0.68, 95% CI 0.50-0.93, p = 0.02, data derived from 10 studies), while symptomatic lymphocele incidence was not significantly different between the two groups (358 vs 373 cases, OR 0.66, 95% CI 0.39-1.10, p = 0.11, data derived from 9 studies). In the subgroup analysis, the incidence difference of lymphoceles between the biomedical material group and control group showed significant association with extension of nodes dissection (p＝0.02) and diagnosis time after surgery (p＝0.02).

Conclusions
The present meta-analysis supports that the use of biomedical materials is effective in reducing the incidence of lymphocele after lymphadenectomy due to gynecologic cancer, and subgroup analysis found the reduction was more significant in the group without para-aortic lymph node dissection, and in the short term after surgery. Further well-designed clinical studies are required to confirm our conclusions.