With the expression of the ERβ-responsive gene set, tumor samples were clustered (average linkage) into two major groups with statistically significant association with 10-year relapse (Fisher exact p = 0.0015), death (Fisher exact p = 0.0401), and tumor grade (Fisher exact p = 0.0128) as compared to the distribution of the parameters tested in the study population. The gene discussed is ESR2; the disease is neoplasm.