RESUMO
Objective:To compare the dosimetric differences between accelerated partial breast irradiation intensity modulated radiation therapy (APBI-IMRT) and whole breast irradiation with simultaneous integrated boost intensity modulated radiotherapy (WBI-SIB-IMRT) for early-stage breast cancer after breast-conserving surgery.Methods:A total of 35 patients with early-stage breast cancer in Jilin Province Cancer Hospital between July 2009 and December 2014 after breast-conserving surgery were enrolled. The targeted regions of APBI-IMRT and WBI-SIB-IMRT were created for each patient. The dosimetric difference comparison of the targeted region and normal tissues was evaluated by using dose volume histogram (DVH).Results:There was no significant difference in the dosimetric comparison of gross tumor volume (GTVtb) and planning gross tumor volume (PGTVtb) after correction of cumulative radiation effect (CRE) between WBI-SIB-IMRT group and APBI-IMRT group (both P > 0.05). The dose of clinical target volume (CTV) and planning target volume(PTV) in APBI-IMRT group was higher than that in WBI-SIB-IMRT group [CTV: (4 720±71) cGy vs. (3 889±79) cGy, t = 3.184, P = 0.027; PTV: (4 675±164) cGy vs. (3 807±199) cGy, t = 2.751, P = 0.032] after CRE correction. Compared with WBI-SIB-IMRT group, the dose of ipsilateral lung tissue and left heart tissue in APBI-IMRT group was decreased after CRE correction [(558.5±8.9) cGy vs. (1 304.9±34.4) cGy, t = -7.328, P = 0.001; (35.5±5.3) cGy vs. (843.0±41.5) cGy, t = -8.137, P = 0.001]. V 5/3.6 Gy, V 10/7.3 Gy, V 15/10.9 Gy, V 20/14.6 Gy, V 25/18.2 Gy and V 30/21.9 Gy of the ipsilateral lung and V 30/21.9Gy, V 40/29.2Gy of left heart in all breast cancer patients after two chemotherapy treatments had significant differences (all P = 0.001). Conclusion:Compared with WBI-SIB, APBI-IMRT can improve the dose distribution in target area and reduce the volume of high dose irradiation in organs at risk.
RESUMO
Objective To evaluate the efficacy of accelerated partial breast irradiation ( APBI ) and whole breast irradiation ( WBI ) with simultaneous integrated boost ( SIB ) from the perspective of economics, and provide a reference for postoperative adjuvant therapy mode selection for early-stage breast cancer after breast-conserving surgery. Methods A total of 355 early-stage breast cancer patients who underwent APBI or WBI-SIB after breast-conserving surgery were evaluated on efficacy and cost-effectiveness, of which 177 patients received APBI, and 178 patients received WBI-SIB. Survival analysis was done according to treatment received. NCI-CTC 3.0 was used to score the toxicities. Breast aesthetic outcome were evaluated with Harris standards. Results Median follow-up was 42 months ( 5.8 -92.7 months) . The 3-year locoregional recurrence free survival( LRFS) rates in APBI group and WBI-SIB group were 98.2％ and 97.6％, distant metastasis free survival( DMFS) were 94.3％ and 93.7％, disease-free survival ( DFS) were 93.1％ and 91.6％, and overall survival 95.5％ and 94.3％, respectively, without statistically significant differences(P>0.05). Compared with WBI-SIB group, the acute reaction rates in APBI group decreased from 5. 6％ to 3.4％(χ2 =6.044, P <0. 05), and late reactions from 5.6％ to 2.3％ (χ2 =6.149, P<0. 05), while the cosmetic outcome improved from 88.8％ to 93.8％(χ2 =5.22, P<0. 05). Moreover, the processing average time was shortened by 26.5 d (χ2 =40.76, P<0. 05). Conclusions After breast-conserving surgery, the efficacy of APBI showed no difference from WBI-SIB with respect to 3-year local control, disease-free survival, and overall survival, but displayed a significantly better toxicity profile and cost-effectiveness ratio for early breast cancer patients. It can be used as a good radiotherapy model after breast-conserving surgery in early-stage breast cancer.