title: Cervical cancer incidence in ontario women: differing sociodemographic gradients by morphologic type (adenocarcinoma versus squamous cell).
abstract: OBJECTIVE
  Identify patterns in cervical cancer incidence in Ontario according to neighborhood sociodemographic characteristics over time and by morphologic type.
  
  
  METHODS
  Incident cases of cervical cancer diagnosed from 1991 to 2009 were obtained from the Ontario Cancer Registry. Population data and data on neighborhood sociodemographic characteristics were obtained from the Canadian Census. Age-standardized incidence rates (ASIR) and rate ratios (RRs) with 95% confidence intervals (CIs) were calculated for each sociodemographic characteristic, stratified by morphologic type (squamous cell carcinoma and adenocarcinoma) and time period of diagnosis.
  
  
  RESULTS
  Incidence was 51% higher in the poorest neighborhoods compared with the richest (RR, 1.51; 95% CI, 1.42-1.61) and 7% higher in rural areas compared with urban (RR, 1.07; 95% CI, 1.01-1.13). Incidence of squamous cell carcinoma was significantly higher in the poorest neighborhoods compared with the richest (RR, 1.74; 95% CI, 1.61-1.88), a trend observed for all time periods, and in rural areas compared with urban (RR, 1.10; 95% CI, 1.02-1.18). For adenocarcinoma, ASIRs in the earlier time period (1991-1998) were higher in the poorest neighborhoods compared with richest (RR, 1.26; 95% CI, 1.01-1.57), whereas for the more recent time period (1999-2009), ASIRs were lower for women living in the poorest neighborhoods compared with the richest (RR, 0.82; 95% CI, 0.68-0.99).
  
  
  CONCLUSIONS
  This study identified significantly higher incidence of cervical cancer in low-income neighborhoods in Ontario. The association was especially pronounced for squamous cell carcinoma and varied by time period for adenocarcinoma. Improvements to screening and prevention efforts against oncogenic human papillomavirus strains would increase the detection of cervical cancer, adenocarcinoma especially, and may further reduce cervical cancer incidence.
authors: *Cancer Care Ontario, Toronto; †Division of Gynecologic Oncology, Juravinski Cancer Center, Hamilton; and ‡Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada.
authors: Maegan V
authors: MV
authors: Prummel
authors: Stephanie W
authors: SW
authors: Young
authors: Elisa
authors: E
authors: Candido
authors: Diane
authors: D
authors: Nishri
authors: Laurie
authors: L
authors: Elit
authors: Loraine D
authors: LD
authors: Marrett
mesh_terms: D000230:Adenocarcinoma / Q000453:epidemiology* / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology* / Q000473:pathology; D005260:Female; D006801:Humans; D015994:Incidence; D009864:Ontario / Q000453:epidemiology; D012042:Registries; D012424:Rural Population / Q000706:statistics & numerical data; D012959:Socioeconomic Factors; D014505:Urban Population / Q000706:statistics & numerical data; D002583:Uterine Cervical Neoplasms / Q000453:epidemiology* / Q000473:pathology