Evaluation of the therapeutic effects and recurrence for head and neck cancer after chemoradiotherapy by FDG-PET.
OBJECTIVE
The purpose of this study was to detect early stage recurrence or a residual tumor after chemoradiotherapy by FDG-PET.


METHODS
A total of 51 head and neck cancer lesions in 27 patients were examined-including primary sites and metastatic lymph nodes. The therapeutic effects were evaluated by visual inspection, pre-treatment SUV, post-treatment SUV and % change in SUV.


RESULTS
No local recurrence was observed in 37 of the lesions, while recurrence or a residual tumor was observed in the other 14 lesions after therapy. A significant difference was found between the two groups regarding the post-treatment SUV and the % change in SUV. Taking the post-treatment SUV of 3 and the % change of 60 as a cut-off value, a significant difference was thus found between the recurrence cases and non-recurrence cases. When all lesions were divided into two groups-including the post-treatment SUV>3 and the % change in the SUV<60 group, and the post-treatment SUV<3 or the % change in SUV>60 group, the overall accuracy was 88.2% (45/51). Therefore, it is more useful to predict the prognosis after chemoradiotherapy by a combined analysis of the post-treatment SUV and the % change in SUV. According to the post-treatment PET period, namely, within 4 weeks and from 5 to 15 weeks after treatment, the accuracy was 85.7% (24/28) and 91.3% (21/23), respectively (p=0.5385).


CONCLUSIONS
The results suggest that it may be possible to predict the recurrence even at 4 weeks after treatment. Therefore, the use of a semi-quantitative analysis of FDG-PET between the pre-treatment and post-treatment findings is thus considered to be helpful in choosing the optimal therapy and for making an accurate prognosis.
Hoshikawa
Hiroshi
H
Department of Otolaryngology, Kagawa University, Japan. hiro@med.kagawa-u.ac.jp
Mitani
Tomoo
T
Nishiyama
Yoshihiro
Y
Yamamoto
Yuka
Y
Ohkawa
Motoomi
M
Mori
Nozomu
N
D000293:Adolescent; D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology / Q000532:radiotherapy*; D002648:Child; D003131:Combined Modality Therapy; D005260:Female; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging* / Q000473:pathology; D009367:Neoplasm Staging; D018365:Neoplasm, Residual / Q000000981:diagnostic imaging* / Q000473:pathology; D010039:Otorhinolaryngologic Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology / Q000532:radiotherapy*; D049268:Positron-Emission Tomography; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D055815:Young Adult
D019788:Fluorodeoxyglucose F18