Clinical remission rates in patients with epithelial ovarian cancer in the pandemic versus the pre-pandemic period.

Abstract

e17541 Background: The COVID-19 pandemic presented challenges for patients with ovarian cancer (OC). The objectives of this study were to compare patient remission outcomes following first-line treatment before and after the onset of the pandemic, and to evaluate potential racial/ethnic disparities in remission outcomes during the pandemic. Methods: This retrospective cohort study was conducted at Kaiser Permanente Southern California (KPSC), a large, integrated healthcare delivery system. Patients diagnosed with Stage I-IV epithelial ovarian cancer 01/01/2017-06/30/2021 were included. Pre and post pandemic periods were designated using 03/04/2020 as the cut-off. Data on cancer characteristics and treatment were obtained from KPSC’s electronic medical records. Chart review was conducted to collect data on complete and clinical remission (complete + partial remission) after first course of treatment. Imaging showing no evidence of disease and normal CA 125 values were used to define complete remission. Partial remission was defined as an incomplete response to therapy documented by the treating physician. Other variables included age and stage at diagnosis, race/ethnicity, Charlson’s comorbidity index, neighborhood deprivation index and prior membership. Modified Poisson regression with robust error variance was used to evaluate the association for the pandemic period and race/ethnicity with the remission outcomes. Results: Of 728 patients included, 531 and 197 patients were diagnosed in the pre-pandemic and pandemic periods, respectively. The distributions of the patients’ age, race, and stage were similar between the pre-pandemic and pandemic period. The cohort was racially/ethnically diverse: 46.0% White, 33.5% Hispanic, 7.4% Black, and 13.1% Asian. Complete remission was observed in 406 (76.5%) patients in the pre-pandemic period compared to 149 (75.6%) patients in the pandemic period (p=0.82). Clinical remission was observed in 473 (89.1%) patients in per-pandemic and 176 (89.34%) patients in pandemic period (p=0.92). No statistically significant associations were found between the remission outcomes and the pandemic in the adjusted models. Black patients had lower complete remission rates (but not lower clinical remission rates) compared to White patients in the pandemic period (p=0.06). Of note, Black patients had 67.6% complete remission rate in the pre-pandemic period whereas only 35.3% achieved complete remission in the pandemic period (p=0.01). However, the number of Black patients in the pandemic period was small (N=17). Conclusions: Overall, patients diagnosed with ovarian cancer achieved similar complete and clinical remission rates between the pre-pandemic and pandemic period. Complete remission varies across subgroups of patients. This finding needs to be further investigated with a larger sample.