Survival comparison of chemotherapy vs. chemotherapy plus surgery for women with ovarian cancer with distant metastatic disease (387)

Objectives: Standard treatment of advanced epithelial ovarian cancer (EOC) is a combination of surgical cytoreduction and chemotherapy. However, the impact of cytoreductive surgery for patients with unresectable metastatic disease, in whom optimal cytoreduction is not feasible, is not well described. Methods: The National Cancer Database (NCDB) was used to identify patients with Stage IV EOC with distant organ metastasis at the time of diagnosis, treated from 2005 to 2016. Distant organ metastasis was defined as metastasis to the brain, lung, liver, bone, or distant lymph node. To represent unresectable distant metastasis, a restricted population with only metastasis to the brain, lung, or bone was also analyzed. All patients received chemotherapy with or without surgery. Overall survival was analyzed using the Kaplan-Meier method, Cox proportional hazards models, and propensity score-weighted analyses. In these analyses, the variables included were surgery, age, year of diagnosis, race, Charlson/Deyo Comorbidity Condition (CDCC) Score, facility type, primary insurance, histology, site of metastasis, urban versus rural residence, education, and median household income. Results: We identified 9025 patients with EOC with distant organ metastasis in the NCDB. Among these patients, 2074 received chemotherapy alone, and 6951 received chemotherapy plus surgery (C+S). Those who received chemotherapy alone were older with higher CDCC scores, lived in areas of lower median household incomes, and had lower high school graduation rates. These individuals had a higher proportion of metastatic disease to the liver, bone, or brain. Race was significantly different between groups, with a higher proportion of those receiving chemotherapy alone being Black (12.7% vs 8.2%). Survival was significantly improved for patients who received C+S (HR: 0.46, p<0.0001). Propensity score-weighted analysis similarly showed improved survival for patients undergoing C+S (HR: 0.49, p<0.0001). Individuals who received single-agent chemotherapy had worse overall survival (HR: 1.35, p<0.0001). When accounting for the impact of single-agent chemotherapy on the survival comparison, the benefit of surgery remained significant (HR: 0.47, p<0.0001). In the group defined as unresectable distant metastasis, we identified 1424 patients, of which 396 received chemotherapy alone and 1028 received C+S. A survival benefit was again shown for patients who received C+S, by Cox model (HR: 0.42, p<0.0001) and propensity score-weighted analysis (HR: 0.44, p<0.0001). Conclusions: Despite the poor prognosis associated with Stage IV EOC, obtaining local control with surgery in addition to chemotherapy may provide an added oncologic benefit. Because of the retrospective nature of this analysis, the absolute benefit of surgery for patients with Stage IVB EOC cannot be established. However, this study may provide added value to patient-centered counseling on the role of surgical resection in the setting of ovarian cancer with distant metastatic disease.