Incidence trend for breast cancer among young women in Goiânia, Brazil

Abstract

CONTEXT AND OBJECTIVE: It has been suggested that there has been a large increase in breast cancer incidence among young women over the last decade. The aim of this study was to describe the incidence of breast cancer among young women up to 39 years of age in Goiânia, between 1988 and 2003, and to compare this with other age groups. DESIGN AND SETTING: Retrospective study using the database of the Population-based Cancer Registry of Goiânia, State of Goiás, Brazil. METHODS: The incidence was calculated according to age groups: up to 39 years, 40 to 59 years and 60 years and over. Average annual percentage changes (AAPCs) were estimated for the different age groups using Poisson regression. RESULTS: Over this period, 3,310 new cases were recorded. The standardized incidence was 2.89/100,000 in 1988 and increased to 6.37/100,000 in 2003 (R² = 0.52) for the group aged up to 39 years (p < 0.003). For the group from 40 to 59 years old, the incidence was 14.39/100,000 in 1988 and 41.70/100,000 in 2003 (R² = 0.85; p < 0.001). For the group aged 60 years and over, it was 17.62/100,000 and 28.49/100,000, respectively (R² = 0.67; p < 0.001). The AAPCs were 5.22%, 5.53% and 4.54% for the age groups up to 39, 40 to 59 and 60 years and over, respectively. CONCLUSIONS: The incidence of breast cancer among young women in Goiânia has been increasing significantly, although this change was similar to the increase in other age groups.