PT - JOURNAL ARTICLE AU - L Benoit AU - J Zerbib AU - M Koual AU - HT Nguyen Xuan AU - N Delanoy AU - MA Le Frere Belda AU - E Bentivegna AU - L Fournier AU - AS Bats AU - H Azaïs TI - 236 What can we learn from the 10 mm lymph node size cut-off on the CT in advanced ovarian cancer at the time of interval debulking surgery? AID - 10.1136/ijgc-2021-ESGO.363 DP - 2021 Oct 01 TA - International Journal of Gynecologic Cancer PG - A211--A212 VI - 31 IP - Suppl 3 4099 - http://ijgc.bmj.com/content/31/Suppl_3/A211.2.short 4100 - http://ijgc.bmj.com/content/31/Suppl_3/A211.2.full SO - Int J Gynecol Cancer2021 Oct 01; 31 AB - Introduction/Background*The benefit of a systematic lymphadenectomy is still debated in patients undergoing neo-adjuvant chemotherapy (NACT) followed by interval debulking surgery (IDS) in ovarian cancer (OC). The objective of this study was to evaluate the predictive value of the pre-NACT and post-NACT CT in predicting definitive histological lymph node involvement. The prognostic value of a positive node on the CT was also assessed.Methodology A retrospective, unicentric cohort study was performed including all patients with ovarian cancer who underwent NACT and IDS with a lymphadenectomy between 2005-2018. CT were analyzed blinded to pathology, and nodes with small axis ≥ 10 mm on CT were considered positive. Sensitivity (Se), specificity (Sp), and negative (NPV) and positive predictive values (PPV) and their CI95% were calculated. The 2-year recurrence free survival (RFS) and 5-year overall survival (OS) was compared.Result(s)*158 patients were included, among which 92 (58%) had histologically positive lymph nodes. CT had a Se, Sp, NPV and PPV of 35%, 82%, 47% and 73% before NACT and 20%, 97%, 47% and 91% after NACT, respectively. Patients with nodes considered positive had a non-significant lower 2-year RFS and 5-year OS on the pre-NACT and post-NACT CT. Patients at ‘high risk’ (nodes stayed positive on the CT or became positive after NACT) also had a non-significant lower 2-year RFS and 5-year OS.Abstract 236 Figure 1 Patients with a stage IIB-IV epithelial ovarian cancer who underwent neo-adjuvant chemotherapy (NACT) followed by interval debulking surgery with a systematic lymphadenectomyA. and B. Overall survival (OS, A) and recurrence free survival (RFS, figure B) of patients who had nodes considered positive (≥10mm) versus negative on the pre-NACT CT (computed tomography)C. and D. Overall survival (OS, C) and recurrence free survival (RFS, figure D) of patients who had nodes considered positive (≥10mm) versus negative on the post-NACT CTView this table:Abstract 236 Table 1 Diagnostic value of CT (pre- or post-NACT) in predicting histological involvement of lymph nodes in patients who underwent NACT followed by interval debulking surgery with lymphadenectomy for ovarianView this table:Abstract 236 Table 2 Conclusion*Presence of enlarged lymph nodes on CT is a weak indicator of lymph node involvement in patients with advanced ovarian cancer undergoing NACT. However, it could be used to assess prognosis.