Predictive factors of sentinel lymph node failed mapping in endometrial carcinoma patients: a systematic review and meta-analysis

Objective: In endometrial carcinoma patients, sentinel lymph node bilateral mapping fails in 20-25% of cases, with several factors affecting the likelihood of detection. However, pooled data about predictive factors of failure are lacking. The aim of this systematic review and meta-analysis was to assess the predictive factors of sentinel lymph node failed mapping in endometrial cancer patients undergoing sentinel lymph node biopsy. Methods: A systematic review and a meta-analysis was performed searching all studies assessing predictive factors of sentinel lymph node failed mapping in apparent uterine-confined endometrial cancer patients undergoing sentinel lymph node biopsy through the cervical injection of indocyanine green. The associations between sentinel lymph node failed mapping and predictive factors of failure were assessed, calculating the odds ratio (OR) with 95% confidence intervals. Results: Six studies with a total of 1345 patients were included. Compared with patients with sentinel lymph node bilateral successful mapping, patients with sentinel lymph node failed mapping showed: OR 1.39 (p=0.41) for body mass index >30 kg/m2; OR 1.72 (p=0.24) for menopausal status; OR 1.19 (p=0.74) for adenomyosis; OR 0.86 (p=0.55) for prior pelvic surgery; OR 2.38 (p=0.26) for prior cervical surgery; OR 0.96 (p=0.89) for prior Cesarean section; OR 1.39 (p=0.70) for lysis of adhesions during surgery before sentinel lymph node biopsy; OR 1.77 (p=0.02) for indocyanine green dose <3 mL; OR 1.28 (p=0.31) for deep myometrial invasion; OR 1.21 (p=0.42) for International Federation of Gynecology and Obstetrics (FIGO) grade 3; OR 1.89 (p=0.01) for FIGO stages III-IV; OR 1.62 (p=0.07) for non-endometrioid histotype; OR 1.29 (p=0.25) for lymph-vascular space invasion; OR 4.11 (p<0.0001) for enlarged lymph nodes; and OR 1.71 (p=0.022) for lymph node involvement. Conclusion: Indocyanine green dose <3 mL, FIGO stage III-IV, enlarged lymph nodes, and lymph node involvement are predictive factors of sentinel lymph node failed mapping in endometrial cancer patients.