Gogia A, et al. - Researchers looked at the rates of discordance in biomarker (estrogen receptor [ER], progesterone receptor [PR], and human epidermal growth factor receptor 2 [HER2/neu]) expression in patients with metastatic breast cancer in developing countries, such as India. In patients with stage I, II, and III breast cancer (as per American Joint Committee on Cancer, 7th edition) who developed metastasis at recurrence (N=103 patients), they reviewed paired biomarker status. They found the rates of discordance were 21.3% for ER, 29.1% for PR, and 15.5% for HER2/neu receptor. In the studied cohort, positive to negative ER was seen in 7.8% and negative to positive in 13.6%. Positive to negative PR was noted in 21.4% and negative to positive PR in 7.8%. About 6.8% had positive to negative HER2/neu receptor and 8.7% negative to positive. Change in tumor biology accompanies metastatic disease evolution and results in discordance in receptor status. It is justifiable to repeat biomarker studies at metastatic recurrence, particularly when treatment plans include hormone and targeted therapy.