Kinetic analysis of 3'-deoxy-3'-(18)F-fluorothymidine ((18)F-FLT) in head and neck cancer patients before and early after initiation of chemoradiation therapy.
The purpose of this study was to investigate the kinetic behavior of 3'-deoxy-3'-(18)F-fluorothymidine ((18)F-FLT) before and early after initiation of chemoradiation therapy in patients with squamous cell head and neck cancer.


METHODS
A total of 8 patients with head and neck cancer underwent (18)F-FLT PET scans (7 patients at baseline and after 5 d [10 Gy] of radiation therapy given with concomitant chemotherapy and 1 patient only at baseline). Dynamic PET images were obtained with concurrent arterial or venous blood sampling. Kinetic parameters including the flux constant of (18)F-FLT based on compartmental analysis (K-FLT), the Patlak influx constant (K-Patlak), and standardized uptake value (SUV) were calculated for the primary tumor and (18)F-FLT-avid cervical lymph nodes for all scans.


RESULTS
Mean pretreatment values of uptake for the primary tumor and cervical nodes were 0.075 +/- 0.006 min(-1), 0.042 +/- 0.004 min(-1), and 3.4 +/- 0.5 (mean +/- SD) for K-FLT, K-Patlak, and SUV, respectively. After 10 Gy of radiation therapy, these values were 0.040 +/- 0.01 min(-1), 0.018 +/- 0.016 min(-1), and 1.8 +/- 1.1 for K-FLT, K-Patlak, and SUV, respectively. For all lesions seen on pretherapy and midtherapy scans, the correlation was 0.90 between K-FLT and K-Patlak, 0.91 between K-FLT and SUV, and 0.99 between K-Patlak and SUV.


CONCLUSIONS
The initial (18)F-FLT uptake and change early after treatment in squamous head and neck tumors can be adequately characterized with SUV obtained at 45-60 min, which demonstrates excellent correlation with influx parameters obtained from compartmental and Patlak analyses.
Menda
Yusuf
Y
Department of Radiology, Division of Nuclear Medicine, University of Iowa Hospitals and Clinics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA. yusuf-menda@uiowa.edu
Boles Ponto
Laura L
LL
Dornfeld
Kenneth J
KJ
Tewson
Timothy J
TJ
Watkins
G Leonard
GL
Schultz
Michael K
MK
Sunderland
John J
JJ
Graham
Michael M
MM
Buatti
John M
JM
D000328:Adult; D017024:Chemotherapy, Adjuvant; D003131:Combined Modality Therapy; D003198:Computer Simulation; D015224:Dideoxynucleosides / Q000493:pharmacokinetics*; D005260:Female; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000628:therapy*; D006801:Humans; D007700:Kinetics; D008297:Male; D008657:Metabolic Clearance Rate; D008875:Middle Aged; D008954:Models, Biological; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics*; D018714:Radiotherapy, Adjuvant
D015224:Dideoxynucleosides; D019275:Radiopharmaceuticals; C002854:alovudine