Cervical injection as an alternative to the utero-ovarian ligament for mapping pelvic sentinel lymph node in early-stage ovarian cancer

PurposeIn early-stage ovarian cancer, sentinel lymph node (SLN) mapping using double injection into the utero-ovarian and infundibulo-pelvic ligaments has been postulated. Cervical injection, commonly used in other gynaecologic tumors, may provide a simpler alternative to utero-ovarian injection for pelvic-SLN detection. This study aims to demonstrate whether cervical and utero-ovarian injections drain to the same pelvic SLN using different tracers for each injection site: technetium-99m (99mTc) at cervix and indocyanine green into the utero-ovarian ligament.MethodsThis prospective trial enrolled endometrial cancer patients scheduled for SLN biopsy from July 2023 to May 2024. Each hemipelvis was considered a case. 99mTc was injected at the cervix preoperatively. If 99mTc migration occurred, indocyanine green was injected into the utero-ovarian ligament intraoperatively. Concordance of migration was determined in those hemipelvis with both 99mTc-cervical and indocyanine green utero-ovarian migration.ResultsSeventeen patients (34 hemipelvis) were included. Migration from both injection sites occurred in 17 hemipelvis, identifying the same pelvic-SLN in all cases, being the concordance rate of 100%. Migration of 99mTc or indocyanine green from cervical injection was detected in 91.2% (95% CI 81.6-100%), whereas migration of indocyanine green injection from the utero-ovarian ligament was detected in 73.9% (95% CI 56-91.9%); these detection rates were not significantly different (p = 0.077).ConclusionsLymphatic migration from the cervix to the pelvis seems to be comparable to the migration from the utero-ovarian ligament to the pelvis, with both pathways converging at the same SLN.