Pathology and FDG PET correlation of residual lymph nodes in head and neck cancer after radiation treatment.
BACKGROUND
This study determines if postradiotherapy [18F]fluorodeoxyglucose positron emission tomography (FDG PET) can predict the pathology status of residual cervical lymph nodes in patients undergoing definitive radiotherapy for head and neck squamous cell carcinoma (HNSCC).


METHODS
Patients with stage N2 or higher HNSCC underwent PET and CT imaging after definitive radiotherapy. Patients with radiographically persistent lymphadenopathy underwent either neck dissection or fine needle aspiration (FNA) of the lymph nodes under ultrasound guidance. PET scan results were correlated with the pathologic findings of the residual lymphadenopathy.


RESULTS
Twenty-four hemi-necks in 23 patients with residual lymphadenopathy had neck dissection or FNA. The pathology correlated strongly with the post-RT FDG PET studies. All patients with a negative post-RT FDG PET and those with a maximum standardized uptake value (SUVmax) of less than 3.0 in the post-RT FDG PET were found to be free from residual viable tumor. Using a SUVmax of less than 3.0 as the criterion for a negative FDG PET study, the sensitivity, specificity, positive predictive value, and negative predictive value were 100%, 84.2%, 62.5%, and 100%, respectively.


CONCLUSIONS
A negative post-RT FDG PET is very predictive of negative pathology in the residual lymph node after definitive radiotherapy for advanced HNSCC. A prospective clinical trial is warranted to determine if neck dissection can be withheld in these patients.
Yao
Min
M
Departments of Radiation Oncology, University of Iowa Health Care, Iowa City, IA, USA. min-yao@uiowa.edu
Luo
Pifu
P
Hoffman
Henry T
HT
Chang
Kristi
K
Graham
Michael M
MM
Menda
Yusuf
Y
Tan
Huaming
H
Buatti
John M
JM
D000328:Adult; D000368:Aged; D044963:Biopsy, Fine-Needle; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy; D005260:Female; D019788:Fluorodeoxyglucose F18; D006258:Head and Neck Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy; D006801:Humans; D008207:Lymphatic Metastasis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18