Klayton Tracy L, Ruth Karen, Buyyounouski Mark K, Uzzo Robert G, Wong Yu-Ning, Chen David Y T, Sobczak Mark, Peter Ruth, Horwitz Eric M
Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA.
Pract Radiat Oncol. 2011;1(4):235-242. doi: 10.1016/j.prro.2011.02.003.
PSA doubling time (PSADT) is commonly used as an indication for salvage androgen deprivation therapy (ADT) for PSA failure following RT. Previously, we had shown that PSADT of <12 months is an important predictor of distant metastasis following 3DCRT using the ASTRO definition of BF. We sought to determine if this approach is still valid using the Phoenix definition. METHODS: Eligible patients included 432 men with T1-3N0M0 prostate cancer who demonstrated PSA failure after completing definitive 3DCRT or IMRT from 1989-2005. Endpoints included freedom from distant metastasis (FDM), cause-specific survival (CSS) and overall survival (OS). PSADT was stratified by 0-6, 6-12, 12-18, 18-24, and >24 months. The median follow-up was 95 months (6-207 months). RESULTS: The 7 year FDM, CSS, and OS rates for the entire group were 73%, 77% and 52%, respectively. 7 year FDM was 50% for PSADT <6 months vs. 83% for PSADT >6 months (p=0.0001). 7 year CSS was 61% for PSADT <6 and 85% for PSADT >6 (p=0.0001). 7 year OS was 47% for PSADT <6 and 53% for PSADT >6 (p=0.04). The proportion of men with BF receiving salvage ADT with a PSADT <6 months was 59%, 6-12 was 45%, 12-18 was 42%, 18-24 was 36%, >24 was 28%. ADT was associated with improved 7 year CSS (68% vs. 46%, p=0.015). Of the 314 men with PSADT >6 months, 124 received ADT and 190 were observed. With a median follow-up of 38 months from BF, there was no demonstrable benefit to ADT in the 7 year CSS (87% vs. 79%, respectively; p=0.758). Independent predictors of FDM were PSADT (p<0.0001), GS (p=0.011), and the use of initial ADT (p=0.005). CONCLUSION: PSADT remains a significant predictor of clinical failure and CSS for men treated with 3DCRT or IMRT who fail according to the Phoenix definition. Immediate use of ADT in patients with PSADT <6 months is significantly associated with improved CSS, although the benefit is less apparent in patients with longer PSADT. These results further refine the role of PSADT in predicting which patients may benefit from salvage ADT and those who may be observed expectantly.
前列腺特异性抗原倍增时间（PSADT）通常被用作挽救性雄激素剥夺治疗（ADT）的指标，用于放疗后前列腺特异性抗原（PSA）失败的情况。此前，我们已经表明，按照美国放射肿瘤学会（ASTRO）关于生化复发（BF）的定义，PSADT<12个月是三维适形放疗（3DCRT）后远处转移的重要预测指标。我们试图确定使用凤凰定义时这种方法是否仍然有效。方法：符合条件的患者包括432例T1 - 3N0M0前列腺癌男性患者，他们在1989年至2005年完成确定性3DCRT或调强放疗（IMRT）后出现PSA失败。终点指标包括无远处转移生存（FDM）、疾病特异性生存（CSS）和总生存（OS）。PSADT按0 - 6、6 - 12、12 - 18、18 - 24和>24个月进行分层。中位随访时间为95个月（6 - 207个月）。结果：整个组的7年FDM、CSS和OS率分别为73%、77%和52%。PSADT<6个月时7年FDM为50%，而PSADT>6个月时为83%（p = 0.0001）。PSADT<6个月时7年CSS为61%，PSADT>6个月时为85%（p = 0.0001）。PSADT<6个月时7年OS为47%，PSADT>6个月时为53%（p = 0.04）。PSADT<6个月接受挽救性ADT的BF男性比例为59%，6 - 12个月为45%，12 - 18个月为42%，18 - 24个月为36%，>24个月为28%。ADT与7年CSS改善相关（68%对46%，p = 0.015）。在314例PSADT>6个月的男性中，124例接受了ADT，190例进行观察。从BF开始中位随访38个月，ADT在7年CSS方面没有明显益处（分别为87%对79%；p = 0.758）。FDM的独立预测因素为PSADT（p<0.0001）、 Gleason评分（GS）（p = 0.011）和初始ADT的使用（p = 0.005）。结论：对于根据凤凰定义失败的接受3DCRT或IMRT治疗的男性，PSADT仍然是临床失败和CSS的重要预测指标。PSADT<6个月的患者立即使用ADT与CSS改善显著相关，尽管在PSADT较长的患者中益处不太明显。这些结果进一步明确了PSADT在预测哪些患者可能从挽救性ADT中获益以及哪些患者可以进行观察等待方面的作用。
