Evaluation of Tobacco Use and Her-2 Receptor Expression in Breast Cancer in an Ethnically Diverse Inner-City Population

Background: Tobacco is linked to most cancers however despite overwhelming biological plausibility and decades of epidemiological studies, no association has been established between tobacco and breast cancer. Although estrogen receptor status has been looked at as a variable there has been no evaluation of the role of Her-2 and smoking in breast cancer. Methods: Review of records from patients treated at the University of Miami/Jackson Memorial Hospital from 1998-2012. The incidence of smoking and Her-2 expression in1255 women was evaluated. Data was analyzed by age, race, ethnic group, menopausal status, tumor stage, and ER/PR/Her-2 receptor status. Results: 1255 charts were analyzed with 1094 having full information. Overall rate of Her-2 expression 18.1%. The rate of Her-2 expression was 21.4% in smokers and 17.0% in non-smokers (p = 0.10). The rate of Her-2 expression was 10.8% in Caucasian smokers and 9.8% in Caucasian non-smokers (p = 0.88); 24.5% in smokers of African descent and 17.3% in non-smokers of African descent (p = 0.24); 22.9% in Latino smokers and 17.4% in Latino non-smokers (p = 0.10). The rate of Her-2/ER expression was 9.4% in smokers and 7.9% in non-smokers (p = 0.42); 5.4% in Caucasian smokers and 4.9% in Caucasian non-smokers (p = 0.916); 12.2% in smokers of African descent and 5.9% in non-smokers of African descent (p = 0.11); 9.5% in Latin smokers and 8.8% in Latin non-smokers (p = 0.77). Conclusions: We found non-statistically significant positive associations in all analyses between Her-2 expression with or without ER expression and tobacco exposure when analyzed by ethnicity.