Introduction/Background Surgical Peritoneal Cancer Index (sPCI) has been validated as a prognostic marker in cases of primary advanced epithelial ovarian carcinoma (PAEOC) in upfront setting i.e. primary cytoreductive surgery (PCS). However, sPCI has yet not been validated in patients undergoing interval cytoreductive surgery with an intent of hyperthermic intraperitoneal chemotherapy (ICS-HIPEC) after neo-adjuvant chemotherapy (NACT).

Methodology Patients of ovarian cancer undergoing interval cytoreductive surgery (ICS) after NACT with an intent of hyperthermic intraperitoneal chemotherapy (HIPEC) i.e. ICS-HIPEC were included in the study. Other inclusion criteria were high grade serous carcinoma (HGSC) and stage IIIC or IVA on imaging at presentation. sPCI score and CC score were prospectively calculated and documented for each patient. Effect of sPCI on overall survival (OS), progression free survival (PFS) and completeness of cytoreduction score (CC score) was evaluated.

Results 138 patients underwent ICS-HIPEC with an average sPCI of 7.9. A clinically relevant cut-off of 9 was determined using ROC and the cohort was divided into Low (0–9) & High (>10) sPCI groups. 74.6% achieved complete cytoreduction and 80.4% underwent HIPEC. Complete cytoreduction had a 3-year OS rate of 79.3%, while incomplete cytoreduction had a OS rate of 41.6%. Low sPCI had a 3-year PFS & 3-year OS rate of 77.8% & 89.6%, whereas high sPCI had a PFS & OS rate of 17.9% & 35.9% respectively. sPCI was independently predictive of OS, as shown by multivariate analysis.

Conclusion The sPCI score during ICS-HIPEC can serve as a prognostic indicator in patients with PAEOC. Additionally, a higher sPCI score is associated with a higher probability of incomplete cytoreduction.

Disclosures The authors have no disclosures to make.