TY - JOUR
T1 - Intensity-modulated radiotherapy of nasopharyngeal carcinoma
T2 - A comparative treatment planning study of photons and protons
AU - Taheri-Kadkhoda, Zahra
AU - Björk-Eriksson, Thomas
AU - Nill, Simeon
AU - Wilkens, Jan J.
AU - Oelfke, Uwe
AU - Johansson, Karl Axel
AU - Huber, Peter E.
AU - Münter, Marc W.
N1 - Funding Information:
This study was supported by the King Gustav V Jubilee Clinic Cancer Research Foundation. We thank Dr. Alex Jensen and Professor Oliver Jäkel at DKFZ for their valuable technical and scientific contributions to the study.
PY - 2008/1/24
Y1 - 2008/1/24
N2 - Background: The aim of this treatment planning study was to investigate the potential advantages of intensity-modulated (IM) proton therapy (IMPT) compared with IM photon therapy (IMRT) in nasopharyngeal carcinoma (NPC). Methods: Eight NPC patients were chosen. The dose prescriptions in cobalt Gray equivalent (GyE) for gross tumor volumes of the primary tumor (GTV-T), planning target volumes of GTV-T and metastatic (PTV-TN) and elective (PTV-N) lymph node stations were 72.6 GyE, 66 GyE, and 52.8 GyE, respectively. For each patient, nine coplanar fields IMRT with step-and-shoot technique and 3D spot-scanned three coplanar fields IMPT plans were prepared. Both modalities were planned in 33 fractions to be delivered with a simultaneous integrated boost technique. All plans were prepared and optimized by using the research version of the inverse treatment planning system KonRad (DKFZ, Heidelberg). Results: Both treatment techniques were equal in terms of averaged mean dose to target volumes. IMPT plans significantly improved the tumor coverage and conformation (P < 0.05) and they reduced the averaged mean dose to several organs at risk (OARs) by a factor of 2-3. The low-to-medium dose volumes (0.33-13.2 GyE) were more than doubled by IMRT plans. Conclusion: In radiotherapy of NPC patients, three-field IMPT has greater potential than nine-field IMRT with respect to tumor coverage and reduction of the integral dose to OARs and non-specific normal tissues. The practicality of IMPT in NPC deserves further exploration when this technique becomes available on wider clinical scale.
AB - Background: The aim of this treatment planning study was to investigate the potential advantages of intensity-modulated (IM) proton therapy (IMPT) compared with IM photon therapy (IMRT) in nasopharyngeal carcinoma (NPC). Methods: Eight NPC patients were chosen. The dose prescriptions in cobalt Gray equivalent (GyE) for gross tumor volumes of the primary tumor (GTV-T), planning target volumes of GTV-T and metastatic (PTV-TN) and elective (PTV-N) lymph node stations were 72.6 GyE, 66 GyE, and 52.8 GyE, respectively. For each patient, nine coplanar fields IMRT with step-and-shoot technique and 3D spot-scanned three coplanar fields IMPT plans were prepared. Both modalities were planned in 33 fractions to be delivered with a simultaneous integrated boost technique. All plans were prepared and optimized by using the research version of the inverse treatment planning system KonRad (DKFZ, Heidelberg). Results: Both treatment techniques were equal in terms of averaged mean dose to target volumes. IMPT plans significantly improved the tumor coverage and conformation (P < 0.05) and they reduced the averaged mean dose to several organs at risk (OARs) by a factor of 2-3. The low-to-medium dose volumes (0.33-13.2 GyE) were more than doubled by IMRT plans. Conclusion: In radiotherapy of NPC patients, three-field IMPT has greater potential than nine-field IMRT with respect to tumor coverage and reduction of the integral dose to OARs and non-specific normal tissues. The practicality of IMPT in NPC deserves further exploration when this technique becomes available on wider clinical scale.
UR - http://www.scopus.com/inward/record.url?scp=40749154787&partnerID=8YFLogxK
U2 - 10.1186/1748-717X-3-4
DO - 10.1186/1748-717X-3-4
M3 - Article
C2 - 18218078
AN - SCOPUS:40749154787
SN - 1748-717X
VL - 3
JO - Radiation Oncology
JF - Radiation Oncology
IS - 1
M1 - 4
ER -