CAJ | 학술논문

目的探讨乳腺癌改良根治术后放疗(PMRT)3种照射技术靶区和患侧肺剂量分布的特点,评价其对降低患侧肺受量的作用.方法对28例Ⅱ、Ⅲ期乳腺癌根治术后患者分别进行胸壁区2个切线适形野(半野)加锁骨上区调强放疗(3D-CRT+ IMRT)、胸壁区加锁骨上区一体调强放疗(IMRT),以及胸壁区2个切线适形野(半野)加锁骨上区电子线单野放疗技术(3D-CRT+ E)的计划设计,通过剂量体积直方图(DVH)评价靶区剂量以及患侧肺V5、V10、V20及V45受照射体积,处方剂量为50.4 Gy(1.8 Gy×28次).结果靶区适形指数(CI) 3D-CRT+ IMRT组(0.61 ±0.03)和IMRT组(0.62±0.03)之间差异无统计学意义(q=2.16,P＞0.05),这两组CI均优于3DCRT+E组[(0.44±0.02),q=20.50、22.66,P＜0.01]；不均匀指数(HI) 3D-CRT+ IMRT组(1.17±0.02)和IMRT组(1.15±0.02)之间差异无统计学意义(q=1.66,P＞0.05),这两组HI均优于3DCRT+E组[(1.24±0.04),q=3.91、5.58,P＜0.01]；患侧肺V5、V10,3D-CRT+E组(48.70％±3.24％,38.56％±3.70％)、3D-CRT+ IMRT组(49.12％±3.03％,38.38％±3.56％)明显少于IMRT组[(77.18％±8.01％,53.07％±6.85％),q=20.35、20.05、12.10、12.24,P＜0.01],3D-CRT+E、3D-CRT+ IMRT两组之间差异无统计学意义(q =0.30、0.14,P＞0.05)；患侧肺V20,3D-CRT+ IMRT组(26.57％±2.51％)、IMRT组(25.22％±2.77％)优于3D-CRT+E组[(31.79％±3.00％),q=5.27、8.21,P＜0.01],3D-CRT+ IMRT、IMRT两组之间差异无统计学意义(q =2.76,P＞0.05)；V453种计划之间差异无统计学意义(F=0.69,P＞0.05).结论在PMRT中应用3D-CRT+ IMRT照射技术在不增加设备投入的情况下能有效地降低患侧肺受照射剂量.
목적 탐토유선암개량근치술후방료(PMRT)3충조사기술파구화환측폐제량분포적특점,평개기대강저환측폐수량적작용.방법 대28례Ⅱ、Ⅲ기유선암근치술후환자분별진행흉벽구2개절선괄형야(반야)가쇄골상구조강방료(3D-CRT+ IMRT)、흉벽구가쇄골상구일체조강방료(IMRT),이급흉벽구2개절선괄형야(반야)가쇄골상구전자선단야방료기술(3D-CRT+ E)적계화설계,통과제량체적직방도(DVH)평개파구제량이급환측폐V5、V10、V20급V45수조사체적,처방제량위50.4 Gy(1.8 Gy×28차).결과 파구괄형지수(CI) 3D-CRT+ IMRT조(0.61 ±0.03)화IMRT조(0.62±0.03)지간차이무통계학의의(q=2.16,P＞0.05),저량조CI균우우3DCRT+E조[(0.44±0.02),q=20.50、22.66,P＜0.01]；불균균지수(HI) 3D-CRT+ IMRT조(1.17±0.02)화IMRT조(1.15±0.02)지간차이무통계학의의(q=1.66,P＞0.05),저량조HI균우우3DCRT+E조[(1.24±0.04),q=3.91、5.58,P＜0.01]；환측폐V5、V10,3D-CRT+E조(48.70％±3.24％,38.56％±3.70％)、3D-CRT+ IMRT조(49.12％±3.03％,38.38％±3.56％)명현소우IMRT조[(77.18％±8.01％,53.07％±6.85％),q=20.35、20.05、12.10、12.24,P＜0.01],3D-CRT+E、3D-CRT+ IMRT량조지간차이무통계학의의(q =0.30、0.14,P＞0.05)；환측폐V20,3D-CRT+ IMRT조(26.57％±2.51％)、IMRT조(25.22％±2.77％)우우3D-CRT+E조[(31.79％±3.00％),q=5.27、8.21,P＜0.01],3D-CRT+ IMRT、IMRT량조지간차이무통계학의의(q =2.76,P＞0.05)；V453충계화지간차이무통계학의의(F=0.69,P＞0.05).결론 재PMRT중응용3D-CRT+ IMRT조사기술재불증가설비투입적정황하능유효지강저환측폐수조사제량.
Objective To identify the best technique of postmastectomy radiation therapy (PMRT).Methods Twenty-eight patients with stage Ⅱ or Ⅲ invasive breast cancer were treated with modified radical mastectomy and radiotherapy sequaciously involving the supraclavicular region and the chest wall.Three different techniques were developed for each patient:two tangential conformal fields ( half field) in the chest wall plus supraclavicular intensity modulated radiotherapy (3D-CRT + IMRT),integrated chest wall and supraclavicular IMRT(IMRT),and two tangential conformal fields (half field) in the chest wall plus single field electron beam radiotherapy in the supraclavicular region( 3D-CRT + E).The dose distributions of the target areas and the irradiated volumes of the ipsilateral lung ( V5,V10,V20,and V45)were estimated with the dosage volume histogram (DVH).The dosage prescription was 50.4 Gy (1.8 Gy × 28 f).Results The conformity index (CI) of the 3D-CRT + IMRT group was (0.61 ± 0.03),not different from that of the IMRT [ (0.62 ±0.03),q =2.16,P ＞0.05],and the CI levels of these 2 groups were both higher than that of the 3D-CRT + E group [ (0.44 ± 0.02 ),q =20.50,22.66,P ＜0.01 ].The heterogeneity index (HI) of the 3D-CRT + IMRT group was ( 1.17 ±0.02),not different from that of the IMRT [ (1.15 ±0.02),q =1.66,P ＞0.05],and the HI levels of these 2 groups were both lower than that of the 3D-CRT + E group[ ( 1.24 ±0.04),q =3.91,5.58,P ＜0.01 ].The levels of V5 and V10 of the ipsilateral lungs of the 3D-CRT + E group(48.70％ ±3.24％,38％.56％ ±3.70％ ) and 3D-CRT + IMRT group (49.12％ ±3.03％,38.38％ ± 3.56％ ) were all significantly lower than those of the IMRTgroup [(77.18％ ±8.01％,53.07％ ±6.85％),V5,q =20.35,20.05,P＜0.01; V10,q=12.10,12.24,P ＜0.01 ] and there were not significant differences in the V5 and V10 levels between the 3D-CRT + E and 3D-CRT + IMRT groups ( q =0.30,0.14,P ＞ 0.05 ).The levels of V20 of the ipsilateral lungs of the 3D-CRT + IMRT group (26.57％ ±2.51％ )and IMRT group (25.22％ ±2.77％) were all significantly lower that those of the 3D-CRT + E group [ (31.79％ ± 3.00％ ),q =5.27,8.21,P ＜ 0.01 ]and there were not significant differences in the V20 level between the 3D-CRT + IMRT and IMRT groups (q=2.76,P ＞ 0.05 ).There were not significant differences in the V45 levels among these 3 groups (F =0.69,P ＞ 0.05).Conclusions The 3D-CRT + IMRT technique in PMRT effectively reduces the radiated dose on the ipsilateral lung.