Learning curve of MRI-based planning for high-dose-rate brachytherapy for prostate cancer

详细信息    查看全文

• 作者：Simon Buus¹ ; ^{simbuu@rm.dk" class="auth_mail" title="E-mail the corresponding author} ; Susanne Rylander¹ ; Steffen Hokland¹ ; Christian Skou Sø ; ndergaard¹ ; Erik Morre Pedersen² ; Kari Tanderup¹ ; ³ ; Lise Bentzen¹
• 关键词：HDR ; Workflow ; Morbidity ; MRI ; Prostate cancer ; Learning curve
• 刊名：Brachytherapy
• 出版年：2016
• 出版时间：July-August 2016
• 年：2016
• 卷：15
• 期：4
• 页码：426-434
• 全文大小：731 K

文摘

To evaluate introduction of MRI-based high-dose-rate brachytherapy (HDRBT), including procedure times, dose-volume parameters, and perioperative morbidity.

Methods and Materials

Study included 42 high-risk prostate cancer patients enrolled in a clinical protocol, offering external beam radiotherapy + two HDRBT 8.5 Gy boosts. Time was recorded for initiation of anesthesia (A), fixation of needle implant (B), end of MR imaging (C), plan approval (D), and end of HDRBT delivery (E). We defined time A–E as total procedure time, A–B as operating room time, B–C as MRI procedure time, C–D as treatment planning time, and D to E as treatment delivery time. Dose-volume parameters were retrieved from the dose planning system. Results from the first 21 patients were compared with the last 21 patients.

Results

Total procedure time, operating room time, MRI procedure time, and treatment planning time decreased significantly from average 7.6 to 5.3 hours (p < 0.01), 3.6 to 2.4 hours (p < 0.01), 1.6 to 0.8 hours (p < 0.01), and 2.0 to 1.3 hours (p < 0.01), respectively. HDRBT delivery time remained unchanged at 0.5 hours. Clinical target volume _prostate+3mmD₉₀ fulfilled planning aim in 92% of procedures and increased significantly from average 8.3 to 9.0 Gy (p < 0.01). Urethral D_{0.1 cm³} and rectal D_{2 cm³} fulfilled planning aim in 78% and 95% of procedures, respectively, and did not change significantly. Hematuria occurred in (95%), hematoma (80%), moderate to strong pain (35%), and urinary retention (5%) of procedures.

Conclusions

After introduction of MRI-based HDRBT, procedure times were significantly reduced. D₉₀ Clinical target volume_prostate+3mm fulfilled constraints in most patients and improved over time, but not at expense of an increased urethral or rectal dose.