Park Seol Hoon, Ryu Jin-Sook, Oh Seung-Jun, Park Seung-Il, Kim Yong Hee, Jung Hoon-Yong, Lee Gin Hyug, Song Ho Jun, Kim Jong Hoon, Song Ho-Young, Cho Kyoung Ja, Kim Sung-Bae
Department of Nuclear Medicine, Asan Medical Center, University of Ulsan College of Medicine, 388-1 Pungnap-2dong, Songpa-gu, Seoul, 138-736 South Korea.
Department of Thoracic Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, 138-736 South Korea.
Nucl Med Mol Imaging. 2012 Mar;46(1):57-64. doi: 10.1007/s13139-011-0118-4. Epub 2012 Jan 3.
The aim of this study was to determine whether (18)F-fluorothymidine (FLT) PET is feasible for the early prediction of tumor response to induction chemotherapy followed by concurrent chemoradiotherapy in patients with esophageal cancer.
This study was prospectively performed as a collateral study of "randomized phase II study of preoperative concurrent chemoradiotherapy with or without induction chemotherapy with S-1/oxaliplatin in patients with resectable esophageal cancer". (18)F-FLT positron emission tomography (PET) images were obtained before and after two cycles of induction chemotherapy, and the percent change of maximum standardized uptake value (SUVmax) was calculated. All patients underwent esophagography, gastrofiberoscopy, endoscopic ultrasonography (EUS), computed tomography (CT) and (18)F-fluorodeoxyglucose (FDG) PET at baseline and 3-4 weeks after completion of concurrent chemoradiotherapy. Final tumor response was determined by both clinical and pathologic tumor responses after surgery.
The 13 patients for induction chemotherapy group were enrolled until interim analysis. In a primary tumor visual analysis, the tumor detection rates of baseline (18)F-FLT and (18)F-FDG PET were 85% and 100%, respectively. The tumor uptakes on (18)F-FLT PET were lower than those of (18)F-FDG PET. Among nine patients who completed second (18)F-FLT PET, eight patients were responders and one patient was a non-responder in the assessment of final tumor response. The percent change of SUVmax in responders ranged from 41.2% to 79.2% (median 57.1%), whereas it was 10.2% in one non-responder.
The percent change of tumor uptake in (18)F-FLT PET after induction chemotherapy might be feasible for early prediction of tumor response after induction chemotherapy and concurrent chemoradiotherapy in patients with esophageal cancer.
本研究旨在确定¹⁸F-氟胸苷（FLT）PET是否可用于早期预测食管癌患者诱导化疗后序贯同步放化疗的肿瘤反应。
本研究作为“可切除食管癌患者术前同步放化疗联合或不联合S-1/奥沙利铂诱导化疗的随机II期研究”的一项附带研究前瞻性开展。在诱导化疗两个周期前后获取¹⁸F-FLT正电子发射断层扫描（PET）图像，并计算最大标准化摄取值（SUVmax）的变化百分比。所有患者在基线时以及同步放化疗完成后3 - 4周接受食管造影、胃镜检查、内镜超声检查（EUS）、计算机断层扫描（CT）和¹⁸F-氟脱氧葡萄糖（FDG）PET检查。最终肿瘤反应通过手术后的临床和病理肿瘤反应来确定。
诱导化疗组的13例患者入组直至中期分析。在原发肿瘤的视觉分析中，基线¹⁸F-FLT和¹⁸F-FDG PET的肿瘤检出率分别为85%和100%。¹⁸F-FLT PET上的肿瘤摄取低于¹⁸F-FDG PET。在完成第二次¹⁸F-FLT PET检查的9例患者中，在最终肿瘤反应评估中，8例患者为反应者，1例患者为无反应者。反应者的SUVmax变化百分比范围为41.2%至79.2%（中位数57.1%），而1例无反应者为10.2%。
诱导化疗后¹⁸F-FLT PET中肿瘤摄取的变化百分比可能有助于早期预测食管癌患者诱导化疗及同步放化疗后的肿瘤反应。
