Different disease progression patterns based on RECIST and CA-125 criteria and the impact on prognosis in patients with ovarian cancer treated with PARP inhibitors.

Abstract

e17536 Background: We aimed to assess the clinical features of disease progression (PD) based on Response Evaluation Criteria in Solid Tumors (RECIST) and CA-125 criteria, and analyse the impact on prognosis in ovarian cancer patients treated with poly (ADP-ribose) polymerase (PARP) inhibitors. Methods: All epithelial ovarian cancer patients included in this retrospective analysis were admitted to the Department of Obstetrics and Gynecology, Qilu Hospital of Shandong University between January 2011 and July 2021. All enrolled patients were treated with PARP inhibitor monotherapy or combination therapy with antiangiogenic agents and regularly assessed with RECIST and CA-125 criteria until disease progression confirmed by RECIST criteria. Patients were divided to RECIST PD group and CA-125 PD group based on regular assessment: RECIST PD group comprised patients who were first confirmed with RECIST-assessed PD and did not achieve PD according to CA-125 criteria during the subsequent 28 days; CA-125 PD group comprised as follows: (i) patients who were first diagnosed with RECIST-assessed PD and defined as consistent if CA-125 PD occurred within the following 28 days; (ii) patients who had doubled CA-125 levels for the first time, confirmed after at least 1 week, and defined as consistent if subsequent RECIST progression occurred within 28 days of the initial doubling of CA-125; (iii) patients in whom the first occurrence of CA-125 was doubled and confirmed after at least 1 week, defined as priority PD of CA-125 provided there was no progression in RECIST assessment during the subsequent 28 days. Results: A total of 124 patients were included, with 64 (51.6%) in RECIST PD group and 60 (48.4%) in CA-125 PD group. Forty-three patients (34.7%) had disease progression consistent with RECIST and CA-125 criteria, 64 patients (51.6%) had priority PD with RECIST criteria, and 17 patients (13.7%) had priority PD with CA-125 criteria. The median interval between disease progression as determined by priority CA-125 criteria and subsequent RECIST criteria was 55 days (range 29–192 days). Patients in CA-125 PD group had a higher proportion of lymph node progression (40.0% vs. 17.2%, p = 0.005), multi-site disease progression (41.7% vs. 21.9%, p=0.018), and a worse prognosis with a median overall survival (OS) of 70.5 vs. 87.2 months (hazard ratio (HR)=2.01, p=0.015). In multivariate analysis, residual lesions after primary surgery (no vs. yes, HR=0.493, p=0.015), duration of PARP inhibitor treatment (≤ 6 vs. > 6 months, HR=2.262, p=0.006), priority criteria for PD (RECIST vs. CA-125, HR=0.441, p=0.006), and BRCA1/2 mutation status (wild-type vs. mutation, HR=2.150, p=0.028) were significantly associated with OS. Conclusions: Priority disease progression based on CA-125 criteria in ovarian cancer patients treated with PARP inhibitors might suggest a poor prognosis.