Your browser doesn't support javascript.
loading
Dosimetry of different techniques in postmastectomy radiation therapy on the ipsilateral lung / 中华放射医学与防护杂志
Chinese Journal of Radiological Medicine and Protection ; (12): 684-687, 2011.
Article in Chinese | WPRIM | ID: wpr-423150
ABSTRACT
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 patienttwo 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.

Full text: Available Index: WPRIM (Western Pacific) Language: Chinese Journal: Chinese Journal of Radiological Medicine and Protection Year: 2011 Type: Article

Similar

MEDLINE

...
LILACS

LIS

Full text: Available Index: WPRIM (Western Pacific) Language: Chinese Journal: Chinese Journal of Radiological Medicine and Protection Year: 2011 Type: Article