Burchardt Wojciech, Skowronek Janusz
Brachytherapy Department, Greater Poland Cancer Centre.
Electroradiology Department, Poznan University of Medical Sciences, Poznan, Poland.
J Contemp Brachytherapy. 2018 Feb;10(1):1-9. doi: 10.5114/jcb.2018.73786. Epub 2018 Feb 26.
To investigate the differences in prostate-specific antigen (PSA) bounce (PB) after high-dose-rate (HDR-BT) or low-dose-rate (LDR-BT) brachytherapy alone in prostate cancer patients.
Ninety-four patients with localized prostate cancer (T1-T2cN0), age ranged 50-81 years, were treated with brachytherapy alone between 2008 and 2010. Patients were diagnosed with adenocarcinoma, Gleason score ≤ 7. The LDR-BT total dose was 144-145 Gy, in HDR-BT - 3 fractions of 10.5 or 15 Gy. The initial PSA level (iPSA) was assessed before treatment, then PSA was rated every 3 months over the first 2 years, and every 6 months during the next 3 years. Median follow-up was 3.0 years.
Mean iPSA was 7.8 ng/ml. In 58 cases, PSA decreased gradually without PB or biochemical failure (BF). In 24% of patients, PB was observed. In 23 cases (24%), PB was observed using 0.2 ng/ml definition; in 10 cases (11%), BF was diagnosed using nadir + 2 ng/ml definition. The HDR-BT and LDR-BT techniques were not associated with higher level of PB (26 vs. 22%, = 0.497). Time to the first PSA rise finished with PB was significantly shorter after HDR-BT then after LDR-BT (median, 10.5 vs. 18.0 months) during follow-up. Predictors for PB were observed only after HDR-BT. Androgen deprivation therapy (ADT) and higher Gleason score decreased the risk of PB (HR = 0.11, = 0.03; HR = 0.51, = 0.01). The higher PSA nadir and longer time to PSA nadir increased the risk of PB (HR 3.46, = 0.02; HR 1.04, = 0.04). There was no predictors for PB after LDR-BT.
HDR-BT and LDR-BT for low and intermediate risk prostate cancer had similar PB rate. The PB occurred earlier after HDR-BT than after LDR-BT. ADT and higher Gleason score decreased, and higher PSA nadir and longer time to PSA nadir increased the risk of PB after HDR-BT.
探讨前列腺癌患者单纯接受高剂量率近距离放疗（HDR-BT）或低剂量率近距离放疗（LDR-BT）后前列腺特异性抗原（PSA）反弹（PB）的差异。
94例局限性前列腺癌（T1-T2cN0）患者，年龄50-81岁，于2008年至2010年间接受单纯近距离放疗。患者均诊断为腺癌，Gleason评分≤7。LDR-BT的总剂量为144-145 Gy，HDR-BT为3次分割，每次10.5或15 Gy。治疗前评估初始PSA水平（iPSA），然后在头2年每3个月评估一次PSA，接下来3年每6个月评估一次。中位随访时间为3.0年。
平均iPSA为7.8 ng/ml。58例患者PSA逐渐下降，无PB或生化复发（BF）。24%的患者出现PB。23例（24%）患者按照0.2 ng/ml的定义出现PB；10例（11%）患者按照最低点+2 ng/ml的定义被诊断为BF。HDR-BT和LDR-BT技术与更高水平的PB无关（26%对22%，P = 0.497）。随访期间，HDR-BT后首次PSA上升至PB结束的时间明显短于LDR-BT后（中位时间，10.5个月对18.0个月）。仅在HDR-BT后观察到PB的预测因素。雄激素剥夺治疗（ADT）和更高的Gleason评分降低了PB的风险（HR = 0.11，P = 0.03；HR = 0.51，P = 0.01）。PSA最低点越高和达到PSA最低点的时间越长，PB的风险增加（HR 3.46，P = 0.02；HR 1.04，P = 0.04）。LDR-BT后未观察到PB的预测因素。
低中危前列腺癌的HDR-BT和LDR-BT的PB率相似。HDR-BT后PB出现的时间早于LDR-BT后。ADT和更高的Gleason评分降低了HDR-BT后PB的风险，而更高的PSA最低点和达到PSA最低点的更长时间增加了HDR-BT后PB的风险。
