Department of Radiation Oncology, National Hospital Organization Osaka National Hospital, Japan.
J Radiat Res. 2012;53(1):154-8. doi: 10.1269/jrr.11142. Epub 2012 Jan 13.
To expand the indications for high-dose-rate interstitial brachytherapy (HDR-ISBT) for deep-seated pelvic tumors, we investigated the usefulness of Doppler transrectal ultrasonography (TRUS) guidance and virtual planning. The patient was a 36-year-old female. She had right internal iliac lymph node oligometastasis of vaginal cancer 12 months after radical radiotherapy. The tumor could not be found by gray-scale TRUS and physical examination. Virtual planning was performed using computed tomography with template and vaginal cylinder insertion. We uploaded the images to our treatment planning software and reconstructed the contours of the clinical target volume (CTV) and right internal iliac vessel. Virtual needle applicators were plotted using the template holes for virtual planning. At the time of implantation, Doppler TRUS was used to prevent vessel injury by needle applicators. Applicators were implanted in accordance with virtual planning and Doppler TRUS could detect the right iliac vessel. The percentage of CTV covered by the prescribed dose was 99.8%. The minimum dose received by the maximally irradiated 0.1-cc volume for the right internal iliac vessel was 95% prescribed dose. Complete response was achieved, however, radiological findings showed marginal recurrence at 15 months after HDR-ISBT. Post-radiation neuropathy occurred as a late complication four months after treatment; however, the pain was well controlled by medication. We consider that virtual planning and Doppler TRUS are effective methods in cases where it is difficult to detect the tumor by physical examination and gray-scale TRUS, thereby expanding the indications for ISBT.
为了扩大高剂量率近距离间质放疗（HDR-ISBT）治疗深部盆腔肿瘤的适应证，我们研究了经直肠超声（TRUS）引导和虚拟计划的有用性。患者为 36 岁女性，根治性放疗 12 个月后出现阴道癌右侧髂内淋巴结寡转移。肿瘤在灰阶 TRUS 和体格检查中均无法找到。使用带有模板和阴道圆筒的 CT 进行虚拟计划。我们将图像上传到我们的治疗计划软件，并重建临床靶区（CTV）和右侧髂内血管的轮廓。使用模板孔绘制虚拟计划的虚拟针插植器。在植入时，使用多普勒 TRUS 防止针插植器损伤血管。根据虚拟计划植入插植器，多普勒 TRUS 可检测到右侧髂血管。CTV 接受处方剂量的百分比为 99.8%。右侧髂内血管接受最大照射 0.1cc 体积的最小剂量为处方剂量的 95%。达到完全缓解，但 HDR-ISBT 后 15 个月影像学检查显示边缘复发。放射后神经病变作为晚期并发症在治疗后四个月发生；然而，疼痛通过药物治疗得到很好的控制。我们认为，在通过体格检查和灰阶 TRUS 难以检测到肿瘤的情况下，虚拟计划和多普勒 TRUS 是有效的方法，从而扩大了 ISBT 的适应证。
