SENSITIVITY AND FALSE NEGATIVITY OF SLN FROZEN SECTIONHISTOLOGICAL EVALUATION IN THE SENTIX TRIAL (CEEGOG-CX01; ENGOT-CX2; NCT02494063)

Introduction/Background* SENTIX is a prospective cohort multicentric international study on sentinel lymph node (SLN) biopsy without pelvic lymph node dissection (PLND) in patients with early-stage cervical cancer. SLN frozen section (FS) and pathological ultrastaging were mandatory by the protocol. Samples from SLN were reviewed centrally for pathological assessment quality control. Only sites experienced in SLN biopsy technique could join the trial. Methodology In total, 47 sites from 18 countries participated in the trial. Patients with FIGO 2009 stages T1A1/LVSI+ – T1B1 ( Result(s)* Altogether 733 patients were registered until Sentix enrolment closure in October 2020, 83 patients were excluded (table 1) and 650 patients was analysed. Patients` characteristics are shown in table 1. Bilateral SLN detection rate reached 95%. FS detected macrometastases (MAC) in 44 cases and micrometastasis (MIC) in 4 cases. SLN ultrastaging found additional 9 cases with MAC, 26 with micrometastases (MIC) and all 19 cases with isolated tumor cells (ITC). Sensitivity of FS was 83.0% for the detection of MAC, 57.8% for pN1 status (MAC or MIC) and 47.1% for any type of SLN involvement (MAC, MIC, ITC). Table 2. Conclusion* High bilateral detection rate of 95% was achieved in Sentix sites experienced in the SLN biopsy technique. Intraoperative pathological assessment of SLN failed to detect majority of MIC (86.7%), all cases with ITC and 42.2% with pN1 (MIC or MAC).