ESR1 and breast carcinoma: As per 2018 statistics, every year around 1.2 million new cases of breast cancer were diagnosed.5 The GLOBACON report of 2018 concluded breast cancer as the most frequently identified cancer type and leading cause of cancer related death in majority of the countries.6 Major part of breast related cancer are linked with the expression of estrogen receptor and their treatment is related with the disease prognosis.5