A 10-unit increase in HSD17B2 expression corresponded with a decrease in the estimated rate of recurrence among ER+/TAM + patients (HR = 0.85, 95% SI 0.69, 1.05), but not among ER-/TAM - patients (HR = 1.07, 95% SI 0.82, 1.42).<h4>Conclusions</h4>HSD17B1 may be a prognostic marker for recurrence and HSD17B2 may be predictive of response to tamoxifen therapy in breast cancer. The gene discussed is ESR1; the disease is breast cancer.