[Breast cancer in México: a 10-year trend analysis on incidence and age at diagnosis].

ABSTRACT

INTRODUCTION: Breast cancer is an important public health problem. Some countries have achieved a downward trend while in others, continues ascending. In México, information on incidence and age at diagnosis is isolated in time, and knowledge on trend analysis is lacking. OBJECTIVE: To examine the 2003-2012 trend of the incidence rate and age at diagnosis of breast cancer in the northeast of México. We also analyze the trend of positivity to nodes, hormone receptors and HER2; and its association with age at diagnosis. MATERIAL AND METHODS: This is an epidemiological study of breast cancer patients in a tertiary care hospital in Monterrey, México (n = 3,488). Only new cases with a histology report were included; if this was not available, the cytology result was considered. Trend analysis was performed using the JoinPoint regression program Version 3.5. RESULTS: The breast cancer incidence rate increased from 26.7 to 49.8 per 100,000 between 2003 and 2011 (p < 0.05). The adjusted rate showed an annual percentage rate of change of +6.2% (95%CI 4.2, 8.2). The mean age was 55.7 ± 13.7 years and remained stable over time. Nodes, hormone receptors and HER2 positivity rate also remained stable over time. Age < 50 years increased twice the risk for positivity to nodes (OR 2.0, 95%CI 1.4, 2.7), ER-PR- (OR 1.8, 95% CI 1.4, 2.4) and ER-PR-HER2- (OR 1.9, 95%CI 1.5, 2.5). CONCLUSIONS: The 10-year analysis showed a significant upward trend. This study represents a first effort in our country, for determining patterns on incidence and age at diagnosis of breast cancer, as well as that of biomarkers.