Purpose: Estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptors (HER) are well-characterized and widely studied breast cancer predictive and prognostic markers that provide important and critical information. The objectives of the current study were to (1) evaluate the trends of ER, PR, and HER tumor markers in breast cancer patients, (2) demonstrate the relationship of ER, PR, and HER status with the age, menopausal status and the site of tumor, (3) evaluate the percentage of HER2 positive patients detected with the Fluorescent in situ hybridization (FISH) technique, and (4) stratify cases according to different molecular subtype classification of breast cancers (ER+PR+HER-, ER+PR-HER1+, ER+PR+HER2+, ER+PR+HER3+, ER-PR+HER1+, ER-PR+HER1+, ER- PR+HER2+ and ER-PR+HER3+).
Methods: The breast cancer subtypes were based on standard Gallen consensus Recommendation (2011). Association between various categorical data was analyzed using Chi-square test followed by Fischer’s exact test. Differences between continuous data were analyzed using student-t test.
Results: A p-value ≤ 0.05 was considered statistically significant. Our study suggests that the incidences of breast cancer were less in the age groups ≤ 40 years (20.6%) and >60 years (18.1%) compared to age groups 41-60 years (56.8%) (p<0.001). We found that younger age group (70 years in western population reported in the literature. While number of ER+ patients in our patient population was 50.0%, number of triple positive patients was15.3%. A high (6.7%) pure PR cases was observed.
Conclusion: In summary, regardless of the hormone status whether it’s single hormone receptor or triple hormone receptor, only age is a variable factor and demonstrates significant difference between HER positive (all the HER2+ cases which are confirmed positive by FISH and HER3+ cases) and negative population. The other two variable factors (menopause and lymph node positivity) are independent of the hormone status.
Breast cancer subtypes; Age; Menopause; Lymph nodes; Overall survival; Hormone receptors
Among all female cancer types, breast cancer is prevailing worldwide and represents at least 25% of all cancer types . Considering different causal factors of breast cancer, age contributes more to that of other factors. Although age-standardized incidence rates in India are lower than in the United Kingdom (UK) (25.8 versus 95 per 100,000), mortality rates are nearly as high (12.7 versus 17.1 per 100,000, respectively) as those of the UK . Worldwide, the mortality rates have exponentially decreased in women since 1990 . Since the incidence of breast cancer is stable (at least from 2004 until 2008), and the treatment plans and diagnosis methods have improved considerably with time, we believe that it has significantly impacted in lowering mortality rate over time. The TNM coding system of staging for breast cancer was initially conceived in 1959 by the American Joint Committee for Cancer (AJCC). The evidence in the literature then available could not support the addition of biomarkers to the TNM staging classification (7th edition). Thus, the TNM staging system was modified (8th edition) for a better understanding of biologic markers, such as estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), and their respective impact on prognosis, selection of therapy, and response .