title: Dosimetric research on intensity-modulated arc radiotherapy planning for left breast cancer after breast-preservation surgery.
abstract: Intensity-modulated radiotherapy (IMRT) has played an important role in breast cancer radiotherapy after breast-preservation surgery. Our aim was to study the dosimetric and implementation features/feasibility between IMRT and intensity-modulated arc radiotherapy (Varian RapidArc, Varian, Palo Alto, CA). The forward IMRT plan (f-IMRT), the inverse IMRT, and the RapidArc plan (RA) were generated for 10 patients. Afterward, we compared the target dose distribution of the 3 plans, radiation dose on organs at risk, monitor units, and treatment time. All 3 plans met clinical requirements, with RA performing best in target conformity. In target homogeneity, there was no statistical significance between RA and IMRT, but both of homogeneity were less than f-IMRT's. With regard to the V(5) and V(10) of the left lung, those in RA were higher than in f-IMRT but were lower than in IMRT; for V(20) and V(30), the lowest was observed in RA; and in the V(5) and V(10) of the right lung, as well as the mean dose in normal-side breast and right lung, there was no statistically significance difference between RA and IMRT, and the lowest value was observed in f-IMRT. As for the maximum dose in the normal-side breast, the lowest value was observed in RA. Regarding monitor units (MUs), those in RA were higher than in f-IMRT but were lower than in IMRT. Treatment time of RA was 84.6% and 88.23% shorter than f-IMRT and IMRT, respectively, on average. Compared with f-IMRT and IMRT, RA performed better in target conformity and can reduce high-dose volume in the heart and left lung-which are related to complications-significantly shortening treatment time as well. Compared with IMRT, RA can also significantly reduce low-dose volume and MUs of the afflicted lung.
authors.affiliation: School of Information Science and Engineering, Shandong University, Ji'nan, China. yinyongsd@yahoo.com.cn
authors.forename: Yong
authors.initials: Y
authors.lastname: Yin
authors.forename: Jinhu
authors.initials: J
authors.lastname: Chen
authors.forename: Tao
authors.initials: T
authors.lastname: Sun
authors.forename: Changsheng
authors.initials: C
authors.lastname: Ma
authors.forename: Jie
authors.initials: J
authors.lastname: Lu
authors.forename: Tonghai
authors.initials: T
authors.lastname: Liu
authors.forename: Ruozheng
authors.initials: R
authors.lastname: Wang
mesh_terms: D000328:Adult; D001943:Breast Neoplasms / Q000532:radiotherapy* / Q000601:surgery*; D005260:Female; D006801:Humans; D008408:Mastectomy; D059351:Organ Sparing Treatments; D011874:Radiometry; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D018714:Radiotherapy, Adjuvant / Q000379:methods; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods*; D016896:Treatment Outcome