Heart and coronary artery protection in patients with mediastinal Hodgkin lymphoma treated with intensity-modulated radiotherapy: dose constraints to virtual volumes or to organs at risk?
OBJECTIVE
To increase heart and coronary artery protection in patients with mediastinal Hodgkin lymphoma treated with intensity-modulated radiotherapy (IMRT).


METHODS
Twenty patients with early-stage mediastinal Hodgkin lymphoma entered the study. IMRT was delivered to the initially involved lymph node volumes. Various virtual volumes (VVs) were designed to improve the protection of the heart and the origin of the coronary arteries, which were the organs at risk (OARs), while preserving adequate PTV coverage. The results obtained with VVs were then compared with those obtained with dose constraints assigned to OARs.


RESULTS
The most satisfactory VV was obtained using the PTV expansion concept. The best compromise between adequate PTV coverage and OAR protection was obtained with dose constraints assigned to the PTV expansion VV and to the origin of the coronary arteries.


CONCLUSIONS
IMRT can be improved by using dose constraints assigned to the PTV expansion VV and/or to the origin of the coronary arteries.
Department of Radiation Oncology, Institut Gustave Roussy, Villejuif, France.
Mithra
M
Ghalibafian
Anne
A
Beaudre
Theodore
T
Girinsky
D000704:Analysis of Variance; D000971:Antineoplastic Combined Chemotherapy Protocols; D003131:Combined Modality Therapy; D003331:Coronary Vessels / Q000528:radiation effects; D006321:Heart / Q000528:radiation effects; D006689:Hodgkin Disease / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy*; D006801:Humans; D008479:Mediastinal Neoplasms / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000517:prevention & control*; D011835:Radiation Protection / Q000379:methods*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D050397:Radiotherapy, Intensity-Modulated; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome