Franciscus Gasthuis and Vlietland, Department of Surgery, Rotterdam, the Netherlands; Erasmus MC, Department of Radiation Oncology, Rotterdam, the Netherlands.
Erasmus MC, Department of Radiation Oncology, Rotterdam, the Netherlands.
Radiother Oncol. 2019 Feb;131:8-13. doi: 10.1016/j.radonc.2018.11.003. Epub 2018 Dec 17.
During oncoplastic breast-conserving surgery (BCS), the surgical cavity is closed to reduce seroma formation. This makes the radiotherapy target definition using clips challenging, leading to poor inter-observer agreement and potentially geographical misses. We hypothesize that injecting a radiopaque hydrogel in the lumpectomy cavity before closure improves radiotherapy target definition and agreement between observers.
Women undergoing BCS in a single university hospital were prospectively accrued in the study. Three to 9 ml of iodined PolyEthylene Glycol (PEG) hydrogel and clips were inserted in the lumpectomy cavity. A CT-scan was performed at 4 to 6 weeks. CT images of BCS patients with standard clips only were used as control group, matched on age, specimen weight, and distance between clips. Six radiation oncologists delineated the tumor bed volumes and rated the cavity visualization scores (CVS). The primary endpoint was the agreement between observers measured using a Conformity Index (Cx).
Forty-two patients were included, 21 hydrogel procedures and 21 controls, resulting in 315 observer pairs. The feasibility of the intervention was 100%. The median Cx was higher in the intervention group (Cx = 0.70, IQR [0.54-0.79]) than in the control group (Cx = 0.54, IQR [0.42-0.66]), p < 0.00, as were the CVS (3.5 [2.5-4.5] versus 2.5 [2-3.5], p < 0.001). The rate of surgical site infections was similar to literature.
The use of radiopaque PEG enables to identify the lumpectomy cavity, resulting in a high inter-observer agreement for radiotherapy target definition. This intervention is easy to perform and blend well into current practice.
在肿瘤整形保乳手术（BCS）中，关闭手术腔以减少血清肿形成。这使得使用夹在放疗靶区定义方面具有挑战性，导致观察者之间的一致性较差，并且可能存在地理漏诊。我们假设在关闭前将不透射线的水凝胶注入切除术腔可改善放疗靶区定义和观察者之间的一致性。
本前瞻性研究纳入了一家大学医院接受 BCS 的女性。将 3 至 9ml 的碘聚乙烯醇（PEG）水凝胶和夹放置在切除术腔中。在 4 至 6 周时进行 CT 扫描。仅使用标准夹的 BCS 患者的 CT 图像作为对照组，按年龄、标本重量和夹之间的距离进行匹配。六名放射肿瘤学家描绘了肿瘤床体积并对腔可视化评分（CVS）进行了评分。主要终点是使用一致性指数（Cx）测量观察者之间的一致性。
共纳入 42 例患者，21 例水凝胶手术，21 例对照，共产生 315 对观察者。该干预措施的可行性为 100%。干预组的中位数 Cx 更高（Cx=0.70，IQR [0.54-0.79]），而对照组为 0.54（IQR [0.42-0.66]），p<0.00，CVS 也是如此（3.5 [2.5-4.5] 比 2.5 [2-3.5]，p<0.001）。手术部位感染的发生率与文献相似。
使用不透射线的 PEG 可识别切除术腔，从而实现放疗靶区定义的高观察者间一致性。这种干预措施易于实施，并且可以很好地融入当前的实践。
