Miles Edward F, Nelson John W, Alkaissi Ali K, Das Shiva, Clough Robert W, Anscher Mitchell S, Oleson James R
Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710, USA.
Brachytherapy. 2008 Apr-Jun;7(2):206-11. doi: 10.1016/j.brachy.2008.01.002. Epub 2008 Mar 24.
To assess the correlation of postimplant dosimetric quantifiers with biochemical control of prostate cancer after low-dose-rate brachytherapy.
Generalized equivalent uniform dose (EUD), dose in Gy to 90% of the prostate gland (D(90)), and percentage of the prostate receiving 100% of the prescribed dose (V(100)) were calculated from the postimplant dose-volume histogram (DVH) for 140 patients undergoing low-dose-rate prostate brachytherapy (LDRPB) monotherapy from 1997 to 2003 at Duke University and the Durham VA Medical Center. Biochemical recurrence was defined according to the American Society for Therapeutic Radiology and Oncology consensus definition.
Median followup after LDRPB was 50 months. There was a 7% biochemical recurrence rate (10/140) at last clinical followup. The median EUD was 167 Gy (range, 41-245). The median D(90) was 139 Gy (range, 45-203). The median V(100) was 88% (range, 44-100). The overall 5-year biochemical recurrence-free survival (bRFS) was 94.2%. The 5-year bRFS was 100% for EUD> or =167 Gy and 89.4% for EUD <167 Gy (p=0.008); 100% for D(90) > or =140 Gy and 90.4% for D(90) <140 Gy (p=0.020); 100% for V(100) > or =88%; and 90.3% for V(100) <88% (p=0.017). There was no statistically significant correlation between any of these factors and overall survival.
In our series of 140 patients with low-risk prostate cancer treated with LDRPB alone, we observed a statistically significant correlation between EUD, D(90), and V(100) and bRFS. The generalized EUD, a calculated value that incorporates the entire prostate DVH, appears to be at least as well correlated with bRFS as D(90) or V(100), and may more completely represent the totality of the dose distribution.
评估低剂量率近距离放射治疗后前列腺癌植入后剂量学定量指标与生化控制之间的相关性。
从1997年至2003年在杜克大学和达勒姆退伍军人事务医疗中心接受低剂量率前列腺近距离放射治疗（LDRPB）单一疗法的140例患者的植入后剂量体积直方图（DVH）中计算广义等效均匀剂量（EUD）、前列腺90%体积所接受的剂量（D(90)）以及接受100%处方剂量的前列腺体积百分比（V(100)）。生化复发根据美国放射肿瘤学会的共识定义来确定。
LDRPB后的中位随访时间为50个月。在最后一次临床随访时，生化复发率为7%（10/140）。EUD的中位数为167 Gy（范围41 - 245）。D(90)的中位数为139 Gy（范围45 - 203）。V(100)的中位数为88%（范围44 - 100）。总体5年无生化复发生存率（bRFS）为94.2%。EUD≥167 Gy时5年bRFS为100%，EUD＜167 Gy时为89.4%（p = 0.008）；D(90)≥140 Gy时为100%，D(90)＜140 Gy时为90.4%（p = 0.020）；V(100)≥88%时为100%，V(100)＜88%时为90.3%（p = 0.017）。这些因素与总生存率之间均无统计学显著相关性。
在我们这组仅接受LDRPB治疗的140例低风险前列腺癌患者中，我们观察到EUD、D(90)和V(100)与bRFS之间存在统计学显著相关性。广义EUD是一个整合了整个前列腺DVH的计算值，其与bRFS的相关性似乎至少与D(90)或V(100)一样好，并且可能更完整地代表剂量分布的总体情况。
