Investigation of the prognostic value of FLT-PET in head and neck tumor.

2006 Fiscal Year Final Research Report Summary

• Project/Area Number: 17591315
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Radiation science
• Research Institution: Foundation of biomedical research and innovation
• Principal Investigator: SAKAMOTO Setsu Foundation of biomedical research and innovation, Dept.of image-based medicine, 分子イメージ研究グループ (40344402)
• Co-Investigator(Kenkyū-buntansha): NAKAMOTO Yuji Kyoto University Graduate School of Medicine, Dept.of Diagnostic Imaging and Nuclear Medicine, 大学院・医学部研究科先端領域融合医学研究機構, 助手(特任) (20360844) ; TOMINAGA Hideyuki Foundation of biomedical research and innovation, Dept.of image-based medicine, Research scientist, 分子イメージ研究グループ, 研究員 (00393348) ; MATSUMOTO Keiichi Foundation of biomedical research and innovation, Dept.of image-based medicine, Research scientist, 分子イメージ研究グループ, 研究員 (60393344) ; SENDA Michio Foundation of biomedical research and innovation, Dept.of image-based medicine, Director, 分子イメージ研究グループ, グループリーダー (00216558)
• Project Period (FY): 2005 – 2006
• Keywords: head and neck tumor / radiation therapy / prognosis / PET / 18-F-FLT / 18-F-FDG

Research Abstract

The aim of the study was to examine the prognostic value of 18F-fluoro-3'-deoxy-3'-L-fluorothymidine (FLT) PET in patients with head and neck cancers, in comparison with FDG PET. Material and methods : We performed whole-body FLT PET and FDG PET on 8 patients (pts) with head and neck cancers, who were planned to receive radiation therapy. However, two pts were excluded, one by unexpected multiple metastases and the other by shortness of follow-up period. We investigated 7 primary or metastatic lesions in six pts with biopsy-proven head and neck cancers, which were positive on both FLT PET and FDG PET. Second whole-body FLT and FDG PET were performed 4 weeks after the completion of therapy in consecutive days. Uptake of FLT and FDG was quantified by the maximum standardized uptake value (SUVmax) prior to and after completion of therapy (FLT-SUVpre, FLT-SUVpost, FDG-SUVpre and FDG-SUVpost, respectively). Decrease rate of SUVmax (%decSUV) between first and second PET were also examined, and compared with the clinical course of the disease. Results : Mean FDG SUV decreased from 11.7 +/-9.7 (range : 3.1-30.2) to 6.0 +/-3.1 (range : 2.9-12.2), as a response to therapy, whereas mean FLT SUV declined from 4.6 +/-1.6 (range : 2.4-6.7) to 2.2 +/-0.6 (range : 1.6-3.1). Mean %decSUV in FDG and FLT PET were 0.27 and 0.42, respectively. Extremely elevated uptake of FDG (FDG-SUVpre >17.0) by two tumors persisted (>9.2) at 4 weeks after the therapy. None of the pts had local recurrence in the radiation field during the clinical follow-up period. Those patients with %decSUV-FDG > 0.59, %decSUV-FLT > 0.57, or those with FLT-SUVpost less than 1.7, had no recurrence of the disease in any region during the follow-up. FLT uptake might be related to prognosis of pts with head and neck cancers.