Dosimetric verification for primary focal hypermetabolism of nasopharyngeal carcinoma patients treated with dynamic intensity-modulated radiation therapy.
OBJECTIVE
To make sure the feasibility with (18F)FDG PET/CT to guided dynamic intensity-modulated radiation therapy (IMRT) for nasopharyngeal carcinoma patients, by dosimetric verification before treatment.


METHODS
Chose 11 patients in III~IVA nasopharyngeal carcinoma treated with functional image-guided IMRT and absolute and relative dosimetric verification by Varian 23EX LA, ionization chamber, 2DICA of I'mRT Matrixx and IBA detachable phantom. Drawing outline and making treatment plan were by different imaging techniques (CT and (18F)FDG PET/CT). The dose distributions of the various regional were realized by SMART.


RESULTS
The absolute mean errors of interest area were 2.39%±0.66 using 0.6 cc ice chamber. Results using DTA method, the average relative dose measurements within our protocol (3%, 3 mm) were 87.64% at 300 MU/min in all filed.


CONCLUSIONS
Dosimetric verification before IMRT is obligatory and necessary. Ionization chamber and 2DICA of I'mRT Matrixx was the effective dosimetric verification tool for primary focal hyper metabolism in functional image-guided dynamic IMRT for nasopharyngeal carcinoma. Our preliminary evidence indicates that functional image-guided dynamic IMRT is feasible.
Department of Radiatiotherapy, Xuzhou Medical College Affiliated Hospital, Xuzhou, China.
Yong
Y
Xin
Jia-Yang
JY
Wang
Liang
L
Li
Tian-You
TY
Tang
Gui-Hong
GH
Liu
Jian-She
JS
Wang
Yu-Mei
YM
Xu
Yong
Y
Chen
Long-Zhen
LZ
Zhang
D002277:Carcinoma; D006257:Head; D006801:Humans; D064847:Multimodal Imaging; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000378:metabolism / Q000473:pathology / Q000532:radiotherapy*; D009333:Neck; D019047:Phantoms, Imaging; D049268:Positron-Emission Tomography; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D050397:Radiotherapy, Intensity-Modulated; D014057:Tomography, X-Ray Computed