A population-level retrospective cohort study was conducted to determine the influence of cervical screening history on the survival from cervical cancer in women 50 years or older.
The study included women diagnosed with invasive cervical cancer in Ontario, Canada, between 2005 and 2012, who were followed for at least 4 years. Screening history was observed for the 5 years before diagnosis. Health care administrative databases were linked to determine demographic, affiliation with primary care physicians, stage (available 2010–2012), treatment, and survival data. Kaplan-Meier and multivariate analyses were carried out to evaluate the impact of cervical screening on overall survival (OS).
There were eligible 1,422 women diagnosed with invasive cervical cancer between 2005 and 2012 of whom 566 had been screened within the 5 years before diagnosis. There were 856 women who did not undergo screening within the 5 years before diagnosis. Unscreened women were more likely to present with locally advanced disease (69.3%) compared with the screened women (42.9%). Four-year OS was significantly greater in the screened group (79.9% vs 58.2%). In our univariate analysis, screening was significantly related to survival (hazard ratio = 2.1, p < .01). In our multivariate analysis after adjusting for age, treatment, affiliation with a primary care physician, and income, screening was still significantly associated with improved survival (hazard ratio = 1.5, p < .01).
Our results demonstrate a survival benefit to screening in women 50 years or older who are diagnosed with cervical cancer. Screening participation must be encouraged in women older than 50 years as rates decline in this age group.