锥形束 CT 观察早期乳癌保乳术后全乳放疗过程中血清肿的体积变化

摘要

目的：评价锥形束CT观察早期乳癌保乳术后全乳放疗过程中血清肿体积变化的临床价值。方法：选取32例早期乳癌保乳术后出现血清肿的全乳放疗患者，采用锥形束CT和普通CT分别在每例患者全乳放疗初次和末次进行扫描成像，然后由2名医师分别在两类CT图像上勾画出血清肿大小，并比较两类CT图像上血清肿的体积变化值、血清肿可见度评分（SCS）和适形指数（CI）。结果：锥形束CT和普通CT图像上的血清肿体积变化值分别为（17．5±7．8）和（17．7±7．7）cm3，差异无统计学意义（t配对＝1．939，P＝0．062）。锥形束CT的SCS和普通CT的SCS一致性较差（Kappa＝0．293，P＝0．005），但两者呈正相关（rS＝0．848，P＜0．001）。锥形束CT的血清肿CI值和普通CT的血清肿CI值呈正相关（rP＝0．882，P＜0．001）。锥形束CT图像上血清肿的CI值和SCS呈正相关（rS＝0．843，P＜0．001），当SCS≥3分时，其CI值＞0．60。结论：锥形束CT可以用来观察早期乳癌保乳术后全乳放疗过程中血清肿的体积变化，尤其是当SCS≥3分时，应用效果最佳。%Aim:To evaluate the clinical value of cone-beam CT in assessing the seroma volume change during whole breast irradiation for early-stage breast cancer after breast conservative surgery .Methods:A total of 32 early-stage breast cancer patients who received breast conservative surgery generating seroma and underwent cone -beam CT scans and conven-tional CT scans at both the initial and the last time of whole breast irradiation were collected .Two senior radiation oncolo-gists contoured seroma on all scans.Seroma volume change, seroma clarity score(SCS), and conformity index(CI) were further examined.Results:The difference in seroma volume change between cone-beam CT [(17.5 ±7.8) cm3 ] and conventional CT [(17.7 ±7.7) cm3] were not statistically significant(tpaired =1.939, P=0.062).SCS of cone-beam CT was not statistically consistent with SCS of conventional CT (Kappa=0.293, P=0.005).SCS of cone-beam CT was posi-tively correlated with SCS of conventional CT (rS =0.848, P<0.001).CI of cone-beam CT was correlated with CI of con-ventional CT(rP =0.882, P<0.001).CI was positively correlated with SCS on cone-beam CT(rS=0.843, P<0.001). When SCS was more than 3 on cone-beam CT, CI was higher than 0.60.Conclusion:Cone-beam CT could detect the se-roma volume change during whole breast irradiation for early-stage breast cancer after breast conservative surgery , especially for SCS≥3.