[Cancer incidence in Italian natives and in first-generation immigrants to Italy].

Objective: The aim of this study was to evaluate differences in cancer incidence in populations born in different countries in the area covered by the Tuscan Cancer Registry.

Setting: We selected cancer cases diagnosed during the period 1998-2005 in the population resident in the provinces of Firenze and Prato. Each case was classified according to the place of birth: a) born in Italy, b) born in countries with high migration (PFPM), born in other highly developed countries (PSA).To compute incidence rates we used as denominator the health regional registry.

Main Outcome Measures: We used the European standard population in computing standardized incidence rates (restricted to the age group 20-59 years) and the standardized rate ratio (SRR) in order to compare subjects born in different countries.

Results: During the period 1998-2005, 14 791 invasive cancers were diagnosed (non-melanoma skin excluded) in subjects aged 20-59 years old, 4.2% in subjects born in countries outside Italy (1.2% in other PSA e 3.0% in PFPM). Incidence in subjects born in PSA did not differ significantly from incidence in subjects born in Italy. Incidence rates among subjects born in PFPM were statistically lower, both in men (151.2 per 100 000) and women (199.3 per 100 000), than in subjects born in Italy (243.5 men e 337.5 women). On the contrary, liver and cervix uteri cancer incidence showed higher rates among subjects born in PFPM (liver: SRR=2.13, p=0.007; cervix uteri: SRR=1.88, p=0.0095).

Conclusion: Subjects born in countries with high migration showed a level of incidence lower than subjects born in Italy (healthy migration effect). Incidence was higher among subjects born in PFPM only for liver and cervix uteri, cancers with a virological aetiology. The migration phenomena open new study prospectives, but also methodological questions (definition of immigrants and of reference populations).