Prognostic factors of biochemical relapse in patients with early stage prostate cancer after brachytherapy / 中华泌尿外科杂志

ABSTRACT

Objective To investigate the prognostic factors of biochemical relapse in patients with early stage prostate cancer after brachytherapy.Methods From December 2003 to December 2007,117 patients (age 51-84 years,median 73 years) with early stage prostate cancer underwent brachytherapy at our hospital.The PSA ranged from 0.4 to 47.6 μg/L (median,14.7 g/L),in which 75 cases with PSA＜ 20.0 μg/L and 42 cases with PSA≥20.0 μg/L.Clinical stage ranged from T1b to T2c.The prostate volume ranged from 13 to 69 ml (average,31 ml),and the percentage of positive biopsy cores was 8％ to 100％ (average,45％),in which 69 cases with a positivity＜50％ and 48 cases with a positivity≥50％.The D90 ranged from 106 to 170 Gy (average,142 Gy).And 6 patients were treated with external beam radiation in combination.The biochemical no evidence of disease (bNED) rate was recorded.And possible prognostic factors,including risk stratification,PSA,clinical stage,prostate volume,biopsy positivity and D90,were analyzed by using SPSS 19.0 software.Results The patients were followed up for 19 to 114 months (average,84 months; median,82 months).And biochemical relapse was observed in 33 cases (bNED rate,72％).The bNED rates in low-risk,intermediate-risk and high-risk groups were 86％,79％ and 64％,respectively and significant correlations were found between bNED rate and risk stratification (P=0.040).Moreover,the bNED rate was significantly higher in patients with the following factors,namely PSA＜20.0 μg/L (P =0.028),percentage of positive biopsy cores＜50％ (P =0.006) and high-dose implants (D90 ≥ 140 Gy) (P=0.009).Conclusions The long-term efficacy of brachytherapy in early stage prostate cancer is definite.Significant associations are found between bNED rate and risk stratification.And higher rates of biochemical relapse could be found in patients with PSA ≥ 20.0 μg/L,percentage of positive biopsy cores ≥ 50％ or D90＜ 140 Gy groups.