ASSOCIATION BETWEEN CLINICAL STAGING AND MOLECULAR SUBTYPES OF BREAST CANCER ACCORDING TO AGE

Karen de Souza Abrahao, Anke Bergmann, Suzana Sales de Aguiar, Eduardo Camargo Millen, Marcelo Aldeodato Bello, Luiz Claudio Santos Thuler,

Institution: INCA

“Objetives: The current study has the goal to identify the frequency of the molecular subtypes according to the age group, and to estimate its association with the clinical staging of the breast cancer. Methods: A cross-sectional study was performed in women with breast cancer, diagnosed and treated between 2008 and 2009, at the age of 18 or over and with information about Immunohistochemical Markers. A descriptive analysis was performed. The chi-square test was used to compare the clinical and demographic characteristics according to the age group. The association between independent variables and the outcome was performed by using Odds Ratio (OR). The data considered clinically and statistically relevant (p <0.20) in the univariate analysis were included in the logistic regression analysis by the stepwise forward method. For all the analysis, p<0.05 was considered statistically significant. Results: 1869 patients were analyzed. Among the young women, there was a greater risk of diagnosis at an advanced stage (≥IIB) in the cases classified as triple negative (OR=5.4; CI95%=1.88-15.84), having the luminal subtype as a reference. Among the non-young women, the risk was increased in the triple negatives cases (OR=2.3; CI95%=1.63-3.26), HER2 (OR=1.8; IC95%=1.24-2.73) and luminal B (OR=1.5; CI95%=1.05-2.14). Conclusion: A greater frequency of triple negative tumors with advanced clinical staging was observed among the young women.

KEYWORDS: Breast cancer, molecular subtypes, clinical staging, age, Brazil”