On the basis of gene expression profiling of breast cancer, the concept of ‘molecular subtypes’ has gained popularity over the last 15 years. Breast cancer is predominantly a disease of aging, with only 5–7% of patients diagnosed with the disease in individuals younger than 40 years. However, the disease in young women is thought to be biologically unique.Aim
The aim of this study was to estimate the frequency of different molecular subtypes of breast carcinoma among young Egyptian patients compared with that in older ones.Materials and methods
The current retrospective study included 60 patients younger than 40 years and 60 patients older than 40 years who had undergone tumor resection in the period January 2012 through October 2016. Immunohistochemical analysis of sections from archival paraffin blocks of breast carcinoma tumor samples was conducted to delineate estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2, Ki-67, and CK5/6 expression with further statistical analysis.Results
Younger patients had significantly higher tumor grade (P=0.001) and more basal-like molecular subtype (P=0.031) compared with older patients who had a significantly more luminal A subtype (P=0.01).Conclusion
Molecular subtypes of breast cancer vary with age with more luminal subtypes seen in elderly patients and more triple-negative basal-like carcinomas encountered in younger patients.