title: Colorectal cancer mortality in two areas of Tuscany with different screening exposures.
abstract: Several randomized trials have demonstrated the efficacy of colorectal cancer screening by the fecal occult blood test in reducing colorectal cancer mortality, but an evaluation of population-based screening programs is still lacking. We compared the colorectal cancer mortality rates (both adjusted rates and 3-year moving average rates) during 1985-2006 for two geographic areas in the provinces of Florence and Prato in the Tuscany region of Italy that began active population-based screening for colorectal cancer at different times: the Empolese-Mugello district, in the early 1980s, and the rest of the Florence and Prato provinces, in early 2000. A log-linear Poisson model was used to estimate the annual percent change in mortality and to examine whether geographic area modified the effect of calendar year on it. The Empolese-Mugello district had a greater decrease in colorectal cancer mortality than the rest of the Florence and Prato provinces (estimated annual percent change in age-adjusted colorectal cancer mortality rate, 2.7% decrease per year [95% confidence interval {CI} = 1.7% to 3.7%] vs 1.3% decrease per year [95% CI = 0.8% to 1.7%], respectively). The interaction between calendar period and area was statistically significant (P < .001). Our results support the hypothesis that the implementation of colorectal cancer screening in the early 1980s in the Empolese-Mugello district, where approximately 17 500 people were tested each year with the fecal occult blood test, was associated with a larger reduction in colorectal cancer mortality than that observed in the rest of Florence and Prato provinces, where screening started 15-20 years later and where approximately 38 000 people were screened each year beginning in 2000.
authors.affiliation: Environmental and Occupational Epidemiology Unit, ISPO Cancer Prevention and Research Institute, Via di S. Salvi 12, 50135 Florence, Italy. a.seniori@ispo.toscana.it
authors.forename: Adele Seniori
authors.initials: AS
authors.lastname: Costantini
authors.forename: Andrea
authors.initials: A
authors.lastname: Martini
authors.forename: Donella
authors.initials: D
authors.lastname: Puliti
authors.forename: Stefano
authors.initials: S
authors.lastname: Ciatto
authors.forename: Guido
authors.initials: G
authors.lastname: Castiglione
authors.forename: Grazia
authors.initials: G
authors.lastname: Grazzini
authors.forename: Marco
authors.initials: M
authors.lastname: Zappa
mesh_terms: D000328:Adult; D000368:Aged; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000401:mortality* / Q000517:prevention & control*; D015986:Confounding Factors, Epidemiologic; D005260:Female; D006801:Humans; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D009780:Occult Blood; D013997:Time Factors