Kikuchi Koyo, Ishii Shuhei, Ieko Yoshiro, Segawa Takafumi, Nakamura Ryuji, Ariga Hisanori
Department of Radiation Oncology, Iwate Medical University, Morioka, JPN.
Department of Urology, Iwate Medical University, Morioka, JPN.
Cureus. 2024 Aug 28;16(8):e68013. doi: 10.7759/cureus.68013. eCollection 2024 Aug.
We aim to investigate the impact of rectal dose reduction of both androgen deprivation therapy (ADT) and concurrent hydrogel spacer placement (HSP) in patients treated with low-dose-rate (LDR) brachytherapy for prostate cancer and to determine whether there are variations in the degree of efficacy of dose reduction across different segments of the rectum.
This study involved 130 consecutive patients treated with I-125 LDR brachytherapy, with (ADT: n = 66) or without (nADT: n = 64) prior ADT, from June 2017 to April 2021. Among these, 13 ADT and 17 nADT patients underwent HSP following induction in May 2020, whereas the remaining patients (nHSP) included 53 ADT and 47 nADT individuals. In the post plan, a rectal dose assessment was made using the rectal volume (RV), divided by horizontal sections into three equal-length subparts (sRVs), such as high-, mid-, and low-RV. The mean sRV values were compared between the nADT and ADT patient groups, both with and without HSP. Similarly, mean sRV was compared between the nHSP and HSP patient groups, both with and without ADT.
In nADT patients, HSP significantly reduced the mean RV of the high-RV (0.002 cc versus 0.086 cc, p < 0.05) and mid-RV (0.127 cc versus 0.377 cc, p < 0.05), but not of the low-RV (0.060 cc versus 0.150 cc, p = 0.06). In contrast, in ADT patients, HSP significantly reduced the RV at all three sites (0.002 cc versus 0.031 cc, p < 0.05; 0.034 cc versus 0.269 cc, p < 0.05; and 0.015 cc versus 0.151 cc, p < 0.05, respectively). No significant difference was observed when comparing mean sRV with or without ADT in both HSP and nHSP patients.
The combination of ADT and HSP for LDR prostate brachytherapy showed the potential to significantly reduce RV, especially in the lower rectum.
我们旨在研究在接受低剂量率（LDR）前列腺癌近距离放射治疗的患者中，雄激素剥夺治疗（ADT）联合水凝胶间隔物置入（HSP）降低直肠剂量的效果，并确定直肠不同节段剂量降低的疗效程度是否存在差异。
本研究纳入了2017年6月至2021年4月期间连续接受I-125 LDR近距离放射治疗的130例患者，其中66例接受过ADT（ADT组），64例未接受过ADT（nADT组）。其中，13例ADT患者和17例nADT患者于2020年5月诱导治疗后接受了HSP，其余患者（nHSP组）包括53例ADT患者和47例nADT患者。在治疗计划制定后，通过直肠体积（RV）进行直肠剂量评估，将直肠水平分为三个等长的子部分（sRV），即高、中、低RV。比较nADT组和ADT组患者在有无HSP情况下的平均sRV值。同样，比较nHSP组和HSP组患者在有无ADT情况下的平均sRV值。
在nADT患者中，HSP显著降低了高RV（0.002 cc对0.086 cc，p<0.05）和中RV（0.127 cc对0.377 cc，p<0.05）的平均RV，但未降低低RV（0.060 cc对0.150 cc，p = 0.06）的平均RV。相比之下，在ADT患者中，HSP显著降低了所有三个部位的RV（分别为0.002 cc对0.031 cc，p<0.05；0.034 cc对0.269 cc，p<0.05；0.015 cc对0.151 cc，p<0.05）。在HSP组和nHSP组患者中，比较有无ADT情况下的平均sRV时，未观察到显著差异。
ADT与HSP联合用于LDR前列腺近距离放射治疗显示出显著降低RV的潜力，尤其是在直肠下部。
