title: Dosimetric Comparison and Evaluation of Three Radiotherapy Techniques for Use after Modified Radical Mastectomy for Locally Advanced Left-sided Breast Cancer.
abstract: This study aimed to compare the post-modified radical mastectomy radiotherapy (PMRMRT) for left-sided breast cancer utilizing 3-dimensional conformal radiotherapy with field-in-field technique (3DCRT-FinF), 5-field intensity-modulated radiation therapy (5F-IMRT) and 2- partial arc volumetric modulated arc therapy (2P-VMAT). We created the 3 different PMRMRT plans for each of the ten consecutive patients. We performed Kruskal-Wallis analysis of variance (ANOVA) followed by the Dunn's-type multiple comparisons to establish a hierarchy in terms of plan quality and dosimetric benefits. P < 0.05 was considered statistically significant. Both 5F-IMRT and 2P-VMAT plans exhibited similar PTV coverage (V95%), hotspot areas (V110%) and conformity (all p > 0.05), and significantly higher PTV coverage compared with 3DCRT-FinF (both p < 0.001). In addition, 5F-IMRT plans provided significantly less heart and left lung radiation exposure than 2P-VMAT (all p < 0.05). The 3DCRT-FinF plans with accurately estimated CTV displacement exhibited enhanced target coverage but worse organs at risk (OARs) sparing compared with those plans with underestimated displacements. Our results indicate that 5F-IMRT has dosimetrical advantages compared with the other two techniques in PMRMRT for left-sided breast cancer given its optimal balance between PTV coverage and OAR sparing (especially heart sparing). Individually quantifying and minimizing CTV displacement can significantly improve dosage distribution.
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, 515031, Guangdong Province, China.
authors.forename: Changchun
authors.initials: C
authors.lastname: Ma
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, 515031, Guangdong Province, China.
authors.forename: Wuzhe
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, 515031, Guangdong Province, China.
authors.forename: Jiayang
authors.initials: J
authors.lastname: Lu
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, 515031, Guangdong Province, China.
authors.forename: Lili
authors.initials: L
authors.lastname: Wu
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, 515031, Guangdong Province, China.
authors.forename: Fangcai
authors.initials: F
authors.lastname: Wu
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, 515031, Guangdong Province, China.
authors.forename: Baotian
authors.initials: B
authors.lastname: Huang
authors.affiliation: Radiology Department, Second Affiliated Hospital, Shantou University Medical College, Shantou 515041, Guangdong Province, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Lin
authors.affiliation: Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, 515031, Guangdong Province, China.
authors.forename: Dongsheng
authors.initials: D
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D015411:Mastectomy, Modified Radical / Q000379:methods*; D008875:Middle Aged; D009367:Neoplasm Staging; D011879:Radiotherapy Dosage; D050397:Radiotherapy, Intensity-Modulated; D000069584:Unilateral Breast Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*