Introduction
To investigate the accuracy and dosimetry of 3D-printing non-coplanar template (3D-PNCT)-assisted computed tomography (CT)-guided iodine-125 seed implantation (125I-SI) for recurrent chest wall cancer (rCWC).

Material and methods
This was a retrospective study of 19 patients with 22 rCWC treated with 3D-PNCT-assisted CT-guided 125I-SI, from Mar 2017 to Mar 2020 in our institute.

Results
Mean needle entrance deviation was 4.50 ±2.70 mm, mean angular deviation was 3.40 ±3.10 degrees, and mean depth deviation was 5.20 ±5.20 mm. No significant difference was found for dosimetric parameters (except conformity index) between pre-plan and post-plan; D90, D100, V100, V150, and V200 were 157.74 ±24.23 and 151.71 ±33.62 (p = 0.228), 85.36 ±34.09 and 70.46 ±23.48 (p = 0.067), 0.93 ±0.04 and 0.90 ±0.07 (p = 0.068), 0.64 ±0.16 and 0.64 ±0.16 (p = 0.984), and 0.35 ±0.17 and 0.37 ±0.18 (p = 0.382) for pre-plan and post-plan, respectively. Conformity index, external index, and homogeneity index were 0.57 ±0.16 and 0.52 ±0.15 (p = 0.007), 0.73 ±0.55 and 0.79 ±0.53 (p = 0.096), and 0.31 ±0.15 and 0.30 ±0.14 (p = 0.504) for pre-plan and post-plan, respectively. Median follow-up time was 8 months (range, 3-30 months). Complete response was observed in 4/22 (18.1%), partial response in 13/22 (59.1%), stable disease in 4/22 (18.1%), and progression disease in 1/22 (4.5%) of the cancers. Among patients with pain before 125I-SI, pain relief rate was 87.5% (7/8). No peri-operative complications of more than grade 2 were observed.

Conclusions
3D-PNCT-assisted CT-guided 125I-SI may be safe and feasible as palliative therapy for non-surgical candidates and painful patients with rCWC.



中文翻译：

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3D打印非共面模板辅助碘125种子植入治疗复发性胸壁癌的准确性和剂量学分析

简介目的
探讨3D打印非共面模板（3D-PNCT）辅助计算机断层扫描（CT）引导的碘125种子植入（125I-SI）对于复发性胸壁癌（rCWC）的准确性和剂量学。

材料与方法
这项回顾性研究自2017年3月至2020年3月在我院进行了19例22rCWC的3D-PNCT辅助CT引导下的125I-SI治疗。

结果
平均针头入口偏差为4.50±2.70 mm，平均角度偏差为3.40±3.10度，平均深度偏差为5.20±5.20 mm。计划前和计划后的剂量参数（合格指数除外）没有显着差异；D90，D100，V100，V150和V200为157.74±24.23和151.71±33.62（p = 0.228），85.36±34.09和70.46±23.48（p = 0.067），0.93±0.04和0.90±0.07（p = 0.068），计划前和计划后分别为0.64±0.16和0.64±0.16（p = 0.984），以及0.35±0.17和0.37±0.18（p = 0.382）。合格指数，外部指数和均质指数分别为0.57±0.16和0.52±0.15（p = 0.007），0.73±0.55和0.79±0.53（p = 0.096），0.31±0.15和0.30±0.14（p = 0.504）前计划和后计划。中位随访时间为8个月（范围3-30个月）。在4/22（18.1％）中观察到完全缓解，在13/22（59.1％）中观察到部分缓解，在4/22（18.1％）中发现稳定的疾病，在1/22（4.5％）的癌症中发现进展。在125I-SI之前有疼痛的患者中，疼痛缓解率为87.5％（7/8）。没有观察到超过2级的围手术期并发症。

结论
3D-PNCT辅助CT引导的125I-SI可能是非手术候选者和rCWC疼痛患者姑息治疗的安全可行的方法。