title: Morphological factors and cardiac doses in whole breast radiation for left-sided breast cancer.
abstract: BACKGROUND
  To investigate the impact of the breast size, shape, maximum heart depth (MDH), and chest wall hypotenuse (the distance connecting middle point of the sternum and the length of lung draw on the selected transverse CT slice) on the volumetric dose to heart with whole breast irradiation (WBI) of left-sided breast cancer patients.
  
  
  METHODS
  Fifty-three patients with left-sided breast cancer undergoing adjuvant intensity-modulated radiotherapy (IMRT) were enrolled in the study. The primary breast size and shape, MHD and DCWH (chest wall hypotenuse) were contoured on radiotherapy (RT) planning CT slices. The dose data of hearts were obtained from the dose-volume histograms (DVHs). Data were analyzed by one-way analysis of variance (ANOVA), Student's t-test and linear regression analysis.
  
  
  RESULTS
  Breast size was independent of heart dose, whereas breast shape, MHD and DCWH were correlated with heart dose. The shapes of breasts were divided into four types, as the flap type, hemisphere type, cone type and pendulous type with heart mean dose being 491.8±234.6 cGy, 752.7±219.0 cGy, 620.2±275.7 cGy, and 666.1±238.0 cGy, respectively. The flap type of breasts shows a strong statistically reduction in heart dose, compared to others (p=0.008 for V30 of heart). DCWH and MHD were found to be the most important parameters correlating with heart dose in WBI.
  
  
  CONCLUSIONS
  More attention should be paid to the heart dose of non-flap type patients. The MHD was found to be the most important parameter to correlate with heart dose in tangential WBI, closely followed by the DCWH, which could help radiation oncologists and physicsts evaluate heart dose and design RT plan in advance.
authors: Department of Radiation Oncology, Shandong's Key Laboratory of Radiation Oncology, Shandong Cancer Hospital, School of Medicine and Life Sciences, University of Jinan and Shandong Academy of Medical Sciences, Jinan, Shandong, China E-mail : baoshli@yahoo.com.
authors: Hui
authors: H
authors: Guan
authors: Yuan-Li
authors: YL
authors: Dong
authors: Li-Jie
authors: LJ
authors: Ding
authors: Zi-Cheng
authors: ZC
authors: Zhang
authors: Wei
authors: W
authors: Huang
authors: Cheng-Xin
authors: CX
authors: Liu
authors: Cheng-Rui
authors: CR
authors: Fu
authors: Jian
authors: J
authors: Zhu
authors: Hong-Sheng
authors: HS
authors: Li
authors: Miao-Miao
authors: MM
authors: Li
authors: Bao-Sheng
authors: BS
authors: Li
mesh_terms: D000328:Adult; D000368:Aged; D001940:Breast / Q000473:pathology* / Q000528:radiation effects*; D005260:Female; D006321:Heart / Q000528:radiation effects*; D006801:Humans; D008875:Middle Aged; D011827:Radiation; D011879:Radiotherapy Dosage; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods; D013909:Thorax / Q000528:radiation effects*; D000069584:Unilateral Breast Neoplasms / Q000473:pathology* / Q000532:radiotherapy*