Germline (CAG) n repeat length of androgen receptor among metastatic prostate cancer patients after endocrine therapy / 中华泌尿外科杂志

ABSTRACT

Objective To investigate the clinical significance of (CAG)n repeats length of androgen receptor (AR) among the patients with metastatic prostate cancer (TxNxM1),and to analyze their relevance to survival.Methods This study retrospectively investigated fifty-three metastatic prostate cancer patients aged 65 years (range 45-87) who were initially treated with endocrine therapy.The length of the (CAG) n repeats of blood samples was determined by both PCR sequencing and fragment analysis.The clinical significance of (CAG)n repeats and its correlation with biochemical progression free survival (bPFS)and overall survival (OS) were investigated.Results The median length of CAG repeats was 21,ranged from 14 to 32.According to the median (CAG)n repeats length,two groups were divided as (CAG)n ≤ 21and(CAG) n≥ 22.The median follow-up was 36 months.Patients with (CAG)n ≤ 21 had significantly shorter OS and bPFS than those with (CAG)n ≥ 22 (P ＜0.05).Shorter CAG repeats remained significant bPFS (HR 2.820,95％CI 1.466-5.427,P=0.002) and OS (HR 5.245,95％CI 1.293-21.27,P=0.020) predictor in multivariate analysis.Conclusions The efficacy of endocrine therapy for metastatic prostate cancer patients maybe influenced by the AR-CAG repeats length,and short (CAG) n repeats predict bad prognosis.