Dosimetric comparison of the simultaneous integrated boost in whole-breast irradiation after breast-conserving surgery: IMRT, IMRT plus an electron boost and VMAT

• Published in: PloS one 2015-03, Vol.10 (3), p.e0120811-e0120811
• Main Authors: Wu, Sangang, Lai, Youqun, He, Zhenyu, Zhou, Yuan, Chen, Shanyu, Dai, Mingming, Zhou, Juan, Lin, Qin, Chi, Feng
• Format: Article
• Language: English
• Subjects: Adult; Biopsy; Breast cancer; Breast Neoplasms - radiotherapy; Breast Neoplasms - surgery; Cancer therapies; Cardiovascular disease; Collaboration; Comparative analysis; Dosimetry; Drug dosages; Electrons; Feasibility studies; Female; Heart; Hospitals; Humans; Irradiation; Laboratories; Lumpectomy; Lungs; Lymphatic system; Mastectomy, Segmental; Middle Aged; Oncology; Organs; Patients; Radiation; Radiation Dosage; Radiation therapy; Radiotherapy; Radiotherapy, Intensity-Modulated - adverse effects; Radiotherapy, Intensity-Modulated - methods; Surgery
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0120811

To compare the target volume coverage and doses to organs at risks (OARs) using three techniques that simultaneous integrated boost (SIB) in whole-breast irradiation (WBI) after breast-conserving surgery, including intensity-modulated radiation therapy (IMRT), IMRT plus an electron boost (IMRT-EB), and volumetric-modulated arc therapy (VMAT). A total of 10 patients with early-stage left-sided breast cancer after breast-conserving surgery were included in this study. IMRT, IMRT-EB and VMAT plans were generated for each patient. The conformity index (CI) of the planning target volumes evaluation (PTV-Eval) of VMAT was significantly superior to those of IMRT and IMRT-EB (P < 0.05). The CI of the PTV Eval-boost of VMAT was better than that of IMRT (P = 0.018) and IMRT-EB (P < 0.001), while the CI of the PTV Eval-boost of IMRT was better than that of IMRT-EB (P = 0.002). The V5, V10 and Dmean in ipsilateral lung with VMAT were significantly higher than IMRT (P < 0.05) and IMRT-EB (P < 0.05). The Dmean, V5 and V10 in heart with VMAT were significantly greater than those of IMRT and IMRT-EB (P < 0.05). There was no significant difference in the OARs between IMRT and IMRT-EB (P > 0.05). Considered the target volume coverage and radiation dose delivered to the OARs (especially the heart and lung), IMRT may be more suitable for the SIB in WBI than IMRT-EB and VMAT. Additional clinical studies with a larger sample size will be needed to assess the long-term feasibility and efficacy of SIB using different radiotherapy techniques.