Seaward S A, Weinberg V, Lewis P, Leigh B, Phillips T L, Roach M
Department of Radiation Oncology, University of California, San Francisco Medical Center 94143, USA.
Cancer J Sci Am. 1998 Nov-Dec;4(6):370-7.
We recently identified a progression-free survival advantage for clinically localized high-risk prostate cancer patients receiving whole-pelvic irradiation. We now seek to identify a subgroup most likely to benefit from whole-pelvic irradiation.
Between October 1987 and December 1995, 506 clinically localized prostate cancer patients were treated with definitive radiotherapy consisting of whole-pelvic irradiation followed by a prostate-only boost, or prostate-only treatment (median follow-up, 35 months vs 30 months). Prostate-specific antigen (PSA) failure was defined as (1) a PSA value > or = 1 ng/mL or (2) a PSA value that rose > or = 0.5 ng/mL in < or = 1 year posttreatment on two consecutive measurements, with the first rise defined as the time of failure. The calculated risk of lymph node positivity (%rLN+) was defined as 2/3 (initial PSA) + 10(Gleason score - 6), with intermediate risk defined as 15% < or = %rLN+ < 35% and highest risk defined as %rLN+ > or = 35%. Univariate and multivariate analyses were performed.
Intermediate-risk patients receiving whole-pelvic irradiation had significantly improved freedom from PSA failure compared with those receiving prostatic irradiation only (median progression-free survival 39.5 months vs 22.5 months; P < 0.0001); highest-risk patients did not (median progression-free survival 27.2 months vs 20.8 months, P = NS). Multivariate analysis revealed type of radiation treatment to be the most significant independent predictor of outcome (P < 0.0001).
Whole-pelvic radiotherapy most significantly improves the PSA failure-free survival in patients with an intermediate calculated risk of lymph node positivity, suggesting that highest-risk patients may present with distant micrometastases.
我们最近发现，接受全盆腔照射的临床局限性高危前列腺癌患者无进展生存期具有优势。我们现在试图确定最有可能从全盆腔照射中获益的亚组。
1987年10月至1995年12月期间，506例临床局限性前列腺癌患者接受了确定性放疗，包括全盆腔照射后仅对前列腺进行追加放疗，或仅对前列腺进行治疗（中位随访时间分别为35个月和30个月）。前列腺特异性抗原（PSA）失败定义为：（1）PSA值≥1 ng/mL，或（2）治疗后1年内连续两次测量PSA值升高≥0.5 ng/mL，首次升高定义为失败时间。计算的淋巴结阳性风险（%rLN+）定义为2/3（初始PSA）+10（ Gleason评分 - 6），中度风险定义为15%≤%rLN+<35%，高风险定义为%rLN+≥35%。进行了单因素和多因素分析。
与仅接受前列腺照射的患者相比，接受全盆腔照射的中度风险患者的PSA失败-free生存期显著改善（中位无进展生存期39.5个月对22.5个月；P<0.0001）；高风险患者则没有（中位无进展生存期27.2个月对20.8个月，P =无显著性差异）。多因素分析显示，放射治疗类型是结果的最显著独立预测因素（P<0.0001）。
全盆腔放疗最显著地改善了淋巴结阳性计算风险为中度的患者的无PSA失败生存期，这表明高风险患者可能存在远处微转移。
