Fröhlich Georgina, Ágoston Péter, Jorgo Kliton, Stelczer Gábor, Polgár Csaba, Major Tibor
Centre of Radiotherapy, National Institute of Oncology, Budapest, Hungary.
Faculty of Science, Eötvös Loránd University, Budapest, Hungary.
Rep Pract Oncol Radiother. 2021 Apr 14;26(2):196-202. doi: 10.5603/RPOR.a2021.0028. eCollection 2021.
The objective of the study was to dosimetrically compare the intensity-modulated-arc-therapy (IMAT), Cyber-Knife therapy (CK), single fraction interstitial high-dose-rate (HDR) and low-dose-rate (LDR) brachytherapy (BT) in low-risk prostate cancer.
Treatment plans of ten patients treated with CK were selected and additional plans using IMAT, HDR and LDR BT were created on the same CT images. The prescribed dose was 2.5/70 Gy in IMAT, 8/40 Gy in CK, 21 Gy in HDR and 145 Gy in LDR BT to the prostate gland. EQD2 dose-volume parameters were calculated for each technique and compared.
EQD2 total dose of the prostate was significantly lower with IMAT and CK than with HDR and LDR BT, D90 was 79.5 Gy, 116.4 Gy, 169.2 Gy and 157.9 Gy (p < 0.001). However, teletherapy plans were more conformal than BT, COIN was 0.84, 0.82, 0.76 and 0.76 (p < 0.001), respectively. The D to the rectum and bladder were lower with HDR BT than with IMAT, CK and LDR BT, it was 66.7 Gy, 68.1 Gy, 36.0 Gy and 68.0 Gy (p = 0.0427), and 68.4 Gy, 78.9 Gy, 51.4 Gy and 70.3 Gy (p = 0.0091) in IMAT, CK, HDR and LDR BT plans, while D to the urethra was lower with both IMAT and CK than with BTs: 79.9 Gy, 88.0 Gy, 132.7 Gy and 170.6 Gy (p < 0.001). D to the hips was higher with IMAT and CK, than with BTs: 13.4 Gy, 20.7 Gy, 0.4 Gy and 1.5 Gy (p < 0.001), while D to the sigmoid, bowel bag, testicles and penile bulb was higher with CK than with the other techniques.
HDR monotherapy yields the most advantageous dosimetrical plans, except for the dose to the urethra, where IMAT seems to be the optimal modality in the radiotherapy of low-risk prostate cancer.
本研究的目的是对低危前列腺癌的调强弧形放疗（IMAT）、射波刀治疗（CK）、单次分割组织间高剂量率（HDR）和低剂量率（LDR）近距离放疗（BT）进行剂量学比较。
选取10例接受CK治疗的患者的治疗计划，并在相同的CT图像上创建使用IMAT、HDR和LDR BT的额外计划。前列腺的处方剂量在IMAT中为2.5/70 Gy，在CK中为8/40 Gy，在HDR中为21 Gy，在LDR BT中为145 Gy。计算每种技术的等效均匀剂量（EQD2）剂量体积参数并进行比较。
IMAT和CK的前列腺EQD2总剂量显著低于HDR和LDR BT，D90分别为79.5 Gy、116.4 Gy、169.2 Gy和157.9 Gy（p<0.001）。然而，远距离放疗计划比BT更适形，适形指数分别为0.84、0.82、0.76和0.76（p<0.001）。HDR BT对直肠和膀胱的剂量低于IMAT、CK和LDR BT，在IMAT、CK、HDR和LDR BT计划中分别为66.7 Gy、68.1 Gy、36.0 Gy和68.0 Gy（p = 0.0427），以及68.4 Gy、78.9 Gy、51.4 Gy和70.3 Gy（p = 0.0091），而IMAT和CK对尿道的剂量均低于BT：79.9 Gy、88.0 Gy、132.7 Gy和170.6 Gy（p<0.
