目的:通过对宫颈癌放疗计划的定量评估,找出宫颈癌放疗计划中存在的问题,以提高计划质量和放疗过程。
方法:我们选择了5月在中山大学肿瘤防治中心接受外放疗的227例宫颈癌患者临床批准的放疗计划,2019年1月,2022年。将这些计划从治疗计划系统转移到PlanIQTM工作站。计划质量指标是根据ICRU83报告的指导方针确定的,GEC-ESTRO工作组,和我们中心的临床要求,并得到了高级临床医生的批准。对放疗计划中存在的问题进行了总结和记录,对低分者进行重新规划,并对差异进行分析.
结果:我们通过定量评估确定了277计划中的几个问题。就GTV而言,不适当的目标体积选择(得分<60),PGTV(CI)和PGTV(V66Gy)的发生率为10.6%,65.2%,还有1%的计划,分别;和PGTV(CI),GTV,和PCTV(D98%,HI)在0.4%中得分为0,10.1%,0.4%,0.4%的计划,分别。危险器官(OAR)的问题主要涉及肠道(直肠,小肠,和结肠),在20.7%的计划中发现,在偶尔的情况下,直肠,小肠,结肠,肾,股骨头得分为0分。在PGTV中,高级规划师的表现明显优于初级规划师(V60Gy,D98%),PCTV(CI),和CTV(D98%)(P≤0.046),尤其是在脊髓和小肠保护方面(P≤0.034)。肠(直肠,俯卧计划的小肠和结肠)剂量明显低于仰卧计划(P<0.05),和目标覆盖率均符合临床要求。选择20个得分较低的放疗计划进行重新计划。重新计划的计划有明显更高的GTV(Dmin)和PTV(V45Gy,D98%)(P<0.05),小肠剂量显着降低(V40GyvsV30Gy),结肠(V40GyvsV30Gy),膀胱(D35%)(P<0.05)。
结论:放疗计划的定量评估不仅可以提高放疗计划的质量,也有利于放射治疗过程的风险管理。
OBJECTIVE: To identify the problems in clinical radiotherapy planning for cervical cancer through quantitative evaluation of the radiotherapy plans to improve the quality of the plans and the radiotherapy process.
METHODS: We selected the clinically approved and administered radiotherapy plans for 227 cervical cancer patients undergoing external radiotherapy at Sun Yat-sen University Cancer Center from May, 2019 to January, 2022. These plans were transferred from the treatment planning system to the Plan IQTM workstation. The plan quality metrics were determined based on the guidelines of ICRU83 report, the GEC-ESTRO Working Group, and the clinical requirements of our center and were approved by a senior clinician. The problems in the radiotherapy plans were summarized and documented, and those with low scores were re-planned and the differences were analyzed.
RESULTS: We identified several problems in the 277 plans by quantitative evaluation. Inappropriate target volume selection (with scores < 60) in terms of GTV, PGTV (CI) and PGTV (V66 Gy) was found in 10.6%, 65.2%, and 1% of the plans, respectively; and the PGTV (CI), GTV, and PCTV (D98%, HI) had a score of 0 in 0.4%, 10.1%, 0.4%, 0.4% of the plans, respectively. The problems in the organs at risk (OARs) involved mainly the intestines (the rectum, small intestine, and colon), found in 20.7% of the plans, and in occasional cases, the rectum, small intestine, colon, kidney, and the femoral head had a score of 0. Senior planners showed significantly better performance than junior planners in PGTV (V60 Gy, D98%), PCTV (CI), and CTV (D98%) (P≤0.046) especially in terms of spinal cord and small intestine protection (P≤0.034). The bowel (the rectum, small intestine and colon) dose was significantly lower in the prone plans than supine plans (P < 0.05), and targets coverage all met clinical requirements. Twenty radiotherapy plans with low scores were selected for re-planning. The re-planned plans had significantly higher GTV (Dmin) and PTV (V45 Gy, D98%) (P < 0.05) with significantly reduced doses of the small intestines (V40 Gy vs V30 Gy), the colon (V40 Gy vs V30 Gy), and the bladder (D35%) (P < 0.05).
CONCLUSIONS: Quantitative evaluation of the radiotherapy plans can not only improve the quality of radiotherapy plan, but also facilitate risk management of the radiotherapy process.