Predictors of Successful Neoadjuvant Chemotherapy and Interval Cytoreductive Surgery in Management of Ovarian Cancer

PURPOSE In patients with ovarian cancer undergoing neoadjuvant chemotherapy (NACT) with the goal of achieving complete interval cytoreductive surgery (ICS), tools are needed to accurately assess NACT efficacy and predict the feasibility of complete ICS after 3-4 cycles. The GINECO group (France) and Gemelli Hospital (Italy) analyzed two independent data sets to evaluate the predictive values of three tools available in routine. METHODS Data from CHIVA randomized phase II trial (ClinicalTrials.gov identifier: NCT01583322 ) and Policlinico Gemelli real-world registry (ID5936-ProtN45) were used to construct the French (N = 185) and Italian data sets (N = 357). Logistic regression models were used to identify the significant predictors—among modeled CA-125 Elimination Rate Constant K (KELIM); radiologic response; and BRCA /homologous recombination deficiency (HRD) status—of the following key indicators of successful ICS after NACT: (1) a low peritoneal carcinomatosis burden (Peritoneal Carcinomatosis Index PCI/Predictive Index Value PIV); (2) a complete CC0-R0 ICS); and (3) a pathologic Chemotherapy Response Score of 3 (CRS3). RESULTS In both French and Italian data sets, a favorable KELIM score ≥1.0 was reproducibly a predictor of higher probability of low PCI/PIV (odds ratios OR, 2.92-4.19); CC0-R0 ICS (OR, 3.66-4.24); and pathologic CRS3 (OR, 2.36-21.44). An objective radiologic response was inconsistently associated with a lower PCI/PIV (OR, 1.78-3.69) and a CC0-R0 ICS (OR, 1.78-5.20). The BRCA /HRD status was not predictive of NACT efficacy. The proportion of patients achieving a CRS3 response was similar regardless of BRCA /HRD status. CONCLUSION In two data sets, the tumor chemosensitivity assessed by the KELIM (online calculator) 29 was a consistent significant predictor of three critical outcomes associated with successful ICS after NACT. The radiologic response was inconsistently associated with lower disease bulk. The BRCA /HRD status was not predictive of NACT efficacy. These outcomes may inform decisions and future chemosensitizing innovative strategies.