Background:The -subunit of human chorionic gonadotropin (hCG) is encoded by four genes, of which expression of the hCG-3, -5, and -8 genes could have prognostic value in breast cancer. Methods: Applying a new, modified Molecular Beacon reverse transcription-PCR assay, we investigated the prognostic value of the hCG-3, -5, and -8 gene transcripts in 129 sporadic unilateral breast cancer samples from patients with a median follow-up of 62.3 months. Results: Expression of hCG-3, -5, -8 was significantly (P ؍ 0.020) associated with relapse-free survival (RFS). In multivariate survival analysis, hCG-3, -5, and -8 maintained prognostic value for RFS, with high expression predicting shorter RFS (P ؍ 0.015; hazard ratio, 2.25; 95% confidence interval, 1.17-4.34). Only 1 of 24 (4%) node-negative patients with low hCG-3, -5, -8 expression relapsed, in contrast to 7 of 26 (27%) patients with high expression (P ؍ 0.046). Conclusions: Expression of hCG-3, -5, -8, which differ by only one nucleotide from other hCG genes, can be assessed by our modified Molecular Beacon assay in breast cancer tissues. Expression of hCG-3, -5, -8 has independent, prognostic value for RFS in breast cancer and may help identify node-negative patients with poor prognosis.