title: 3-D reconstruction of anterior mantle-field techniques in Hodgkin's disease survivors: doses to cardiac structures.
abstract: BACKGROUND
  The long-term dose-effect relationship for specific cardiac structures in mediastinal radiotherapy has rarely been investigated. As part of an interdisciplinary project, the 3-D dose distribution within the heart was reconstructed in all long-term Hodgkin's disease survivors (n = 55) treated with mediastinal radiotherapy between 1978 and 1985. For dose reconstruction, original techniques were transferred to the CT data sets of appropriate test patients, in whom left (LV) and right ventricle (RV), left (LA) and right atrium (RA) as well as right (RCA), left anterior descending (LAD) and left circumflex (LCX) coronary arteries were contoured. Dose-volume histograms (DVHs) were generated for these heart structures and results compared between techniques.
  
  
  RESULTS
  Predominant technique was an anterior mantle field (cobalt-60). 26 patients (47%) were treated with anterior mantle field alone (MF), 18 (33%) with anterior mantle field and monoaxial, bisegmental rotation boost (MF+ROT), 7 (13%) with anterior mantle field and dorsal boost (MF+DORS) and 4 (7%) with other techniques. Mean +/- SD total mediastinal doses for MF+ROT (41.7 +/- 3.5 Gy) and for MF+DORS (42.7 +/- 7.4) were significantly higher than for MF (36.7 +/- 5.2 Gy). DVH analysis documented relative overdosage to right heart structures with MF (median maximal dose to RV 129%, to RCA 127%) which was significantly reduced to 117% and 112%, respectively, in MF+ROT. Absolute doses in right heart structures, however, did not differ between techniques. Absolute LA doses were significantly higher in MF+ROT patients than in MF patients where large parts of LA were blocked. Median maximal doses for all techniques ranged between 48 and 52 Gy (RV), 44 and 46 Gy (LV), 47 and 49 Gy (RA), 38 and 45 Gy (LA), 46 and 50 Gy (RCA), 39 and 44 Gy (LAD) and 34 and 42 Gy (LCX).
  
  
  CONCLUSIONS
  In patients irradiated with anterior mantle-field techniques, high doses to anterior heart portions were partly compensated by boost treatment from non-anterior angles. As the threshold doses for coronary artery disease, cardiomyopathy, pericarditis and valvular changes are assumed to be 30 to 40 Gy, cardiac toxicity must be anticipated in these patients. Thus, dose distributions in individual subjects should be correlated to the corresponding cardiovascular findings in these long-term survivors, e. g. by cardiovascular magnetic resonance imaging.
authors.affiliation: Dept. of Radiation Oncology, University of Würzburg, Germany. vordermark_d@klinik.uni-wuerzburg.de
authors.forename: Dirk
authors.initials: D
authors.lastname: Vordermark
authors.forename: Ines
authors.initials: I
authors.lastname: Seufert
authors.forename: Franz
authors.initials: F
authors.lastname: Schwab
authors.forename: Oliver
authors.initials: O
authors.lastname: Kölbl
authors.forename: Margret
authors.initials: M
authors.lastname: Kung
authors.forename: Christiane
authors.initials: C
authors.lastname: Angermann
authors.forename: Michael
authors.initials: M
authors.lastname: Flentje
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D003331:Coronary Vessels / Q000473:pathology / Q000528:radiation effects; D005260:Female; D006321:Heart / Q000503:physiopathology / Q000528:radiation effects*; D006689:Hodgkin Disease / Q000150:complications / Q000532:radiotherapy*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008482:Mediastinum / Q000473:pathology / Q000528:radiation effects*; D008875:Middle Aged; D011829:Radiation Dosage; D011878:Radiotherapy / Q000009:adverse effects* / Q000379:methods; D011879:Radiotherapy Dosage; D013997:Time Factors