ESR1 and neoplasm: In multivariate analysis of ER+ patients in the GOBO cohort, lower than median expression of the TSTSS was associated with increased risk of distant metastasis (hazard ratio = 1.85, confidence interval = 1.28 to 2.67; P = 0.001; n = 553 evaluable patients), independent of lymph node status, tumor grade, age at diagnosis and tumor size.