18F-deoxyglucose positron emission tomography/computed tomography to predict local failure in esophageal squamous cell carcinoma

// Bingjie Fan 1 , Pingping Fan 1, 2, 3 , Li Kong 1, 2, 3 , Xindong Sun 1, 2, 3 , Shuqiang Zhao 1, 2, 4 , Xiaorong Sun 1, 2, 4 , Zheng Fu 1, 2, 4 , Jinsong Zheng 1, 2, 4 , Li Ma 1, 2, 4 , Shijiang Wang 1, 2, 3 , Man Hu 1, 2, 3 and Jinming Yu 1, 2, 3 1 Shandong Cancer Hospital Affiliated to Shandong University, Jinan, China 2 Shandong Academy of Medical Sciences, Jinan, China 3 Departments of Radiation Oncology and Shandong Province Key Laboratory of Radiation Oncology, Shandong Cancer Hospital and Institute, Jinan, China 4 Departments of Nuclear Medicine, Shandong Cancer Hospital and Institute, Jinan, China Correspondence to: Man Hu, email: hu5770@sina.com Jinming Yu, email: sdyujinming@163.com Keywords: esophageal squamous cell carcinoma, radiotherapy, FDG PET/CT, concurrent chemoradiotherapy, local failure Received: October 15, 2016     Accepted: January 04, 2017     Published: February 22, 2017 ABSTRACT Esophageal squamous cell carcinoma (ESCC) patients are at risk for local failure (LF) following treatment. Predicting tumor regions at high risk for local failure before radiotherapy may increase treatment efficacy by permitting an escalated radiation dose specifically to those regions critical for tumor control. Forty-one patients with non-resectable locally advanced ESCC underwent 18 F-deoxyglucose positron emission tomography/computed tomography (FDG PET/CT) imaging before concurrent chemoradiotherapy (CCRT). After CCRT, a second (failure) FDG PET/CT was performed in cases of relapse. Failure FDG PET/CT scans were fused to pre-treatment scans to identify tumor regions at high risk for LF. Within a median follow-up time of 26 months, 20 patients (48.8%) had LF. In 19 patients, the failure occurred within a pre-treatment high FDG uptake region; the failure occurred outside these regions in only one patient. Pre-treatment metabolic tumor volume (MTV) was independently associated with LF ( P <0.001, HR 1.128, 95% CI: 1.061–1.198). LF was more likely in patients with MTVs ≥27 cm 3 . In initial PET/CT images, when 50% maximum standardized uptake value (SUV max ) was used as the threshold, delineated subvolumes overlapped LF regions. These results confirm that LF occurs most commonly within pre-treatment high FDG uptake regions.