Kinetic Analysis of 3'-Deoxy-3'-18F-Fluorothymidine (18F-FLT) in Head and Neck Cancer Patients Before and Early After Initiation of Chemoradiation Therapy
Yusuf Menda 1*,
Laura L. Boles Ponto 1,
Kenneth J. Dornfeld 2,
Timothy J. Tewson 1,
G. Leonard Watkins 1,
Michael K. Schultz 2,
John J. Sunderland 1,
Michael M. Graham 1,
and
John M. Buatti 2
1 Department of Radiology, University of Iowa Hospitals and Clinics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
2 Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
* To whom correspondence should be addressed. E-mail: yusuf-menda{at}uiowa.edu.
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Abstract |
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The purpose of this study was to investigate the kinetic behavior of 3'-deoxy-3'-18F-fluorothymidine (18F-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 18F-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 18F-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 18F-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. Conclusion: The initial 18F-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.
Key Words:
3'-deoxy-3'-18F-fluorothymidine,
18F-FLT, head and neck cancer
