title: High-volume ovarian cancer care: survival impact and disparities in access for advanced-stage disease.
abstract: OBJECTIVE
  To characterize the impact of hospital and physician ovarian cancer case volume on survival for advanced-stage disease and investigate socio-demographic variables associated with access to high-volume providers.
  
  
  METHODS
  Consecutive patients with stage IIIC/IV epithelial ovarian cancer (1/1/96-12/31/06) were identified from the California Cancer Registry. Disease-specific survival analysis was performed using Cox-proportional hazards model. Multivariate logistic regression analyses were used to evaluate for differences in access to high-volume hospitals (HVH) (≥20 cases/year), high-volume physicians (HVP) (≥10 cases/year), and cross-tabulations of high- or low-volume hospital (LVH) and physician (LVP) according to socio-demographic variables.
  
  
  RESULTS
  A total of 11,865 patients were identified. The median ovarian cancer-specific survival for all patients was 28.2 months, and on multivariate analysis the HVH/HVP provider combination (HR = 1.00) was associated with superior ovarian cancer-specific survival compared to LVH/LVP (HR = 1.31, 95%CI = 1.16-1.49). Overall, 2119 patients (17.9%) were cared for at HVHs, and 1791 patients (15.1%) were treated by HVPs. Only 4.3% of patients received care from HVH/HVP, while 53.1% of patients were treated by LVH/LVP. Both race and socio-demographic characteristics were independently associated with an increased likelihood of being cared for by the LVH/LVP combination and included: Hispanic race (OR = 1.72, 95%CI = 1.22-2.42), Asian/Pacific Islander race (OR = 1.57, 95%CI = 1.07-2.32), Medicaid insurance (OR = 2.51, 95%CI = 1.46-4.30), and low socioeconomic status (OR = 2.84, 95%CI = 1.90-4.23).
  
  
  CONCLUSIONS
  Among patients with advanced-stage ovarian cancer, the provider combination of HVH/HVP is an independent predictor of improved disease-specific survival. Access to high-volume ovarian cancer providers is limited, and barriers are more pronounced for patients with low socioeconomic status, Medicaid insurance, and racial minorities.
authors.affiliation: Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of California, Irvine-Medical Center, Orange, CA, USA. Electronic address: rbristow@uci.edu.
authors.forename: Robert E
authors.initials: RE
authors.lastname: Bristow
authors.affiliation: Department of Epidemiology, University of California, Irvine, CA, USA.
authors.forename: Jenny
authors.initials: J
authors.lastname: Chang
authors.affiliation: Department of Epidemiology, University of California, Irvine, CA, USA.
authors.forename: Argyrios
authors.initials: A
authors.lastname: Ziogas
authors.affiliation: Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of California, Irvine-Medical Center, Orange, CA, USA.
authors.forename: Leslie M
authors.initials: LM
authors.lastname: Randall
authors.affiliation: Department of Epidemiology, University of California, Irvine, CA, USA.
authors.forename: Hoda
authors.initials: H
authors.lastname: Anton-Culver
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002140:California / Q000453:epidemiology; D000077216:Carcinoma, Ovarian Epithelial; D003695:Delivery of Health Care / Q000458:organization & administration / Q000592:standards; D005260:Female; D054625:Healthcare Disparities / Q000706:statistics & numerical data*; D006801:Humans; D008875:Middle Aged; D009375:Neoplasms, Glandular and Epithelial / Q000401:mortality* / Q000473:pathology / Q000628:therapy*; D010051:Ovarian Neoplasms / Q000401:mortality* / Q000473:pathology / Q000628:therapy*; D012189:Retrospective Studies; D012959:Socioeconomic Factors; D016019:Survival Analysis; D055815:Young Adult
keywords: Access to care; Disparities; Ovarian cancer