The value of ¹⁸F-FDG PET/CT in assessment of metabolic response in esophageal cancer for prediction of histopathological response and survival after preoperative chemoradiotherapy

Abstract

Aim.To evaluate the ability of hybrid 18 F-fluorodeoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT) to predict histopathological response and overall survival (OS) after preoperative neoadjuvant chemoradiotherapy (CRT) in patients with the esophageal carcinoma. Methods. 73 patients with locally advanced esophageal carcinoma were included in the study. All were treated with CRT and 34 subsequently underwent surgical resection of the esophagus. 18F-FDG PET/CT was carried out prior to (PET/ CT1) and 6 weeks after (PET/CT2) completion of the CRT. Results. PET/CT2-determined complete metabolic response (CMR) was achieved in 6 (17.6%) out of 34 operated patients, the metabolic response was incomplete (NCMR) in 28 (82.4%) patients. A histopathological complete response (CR) to CRT was discovered in 7 patients (20.6%). The median OS in operated patients was 17.1 months, 95% CI:12.9-23.3 months. In a group of 39 non-operated patients, CMR after neoadjuvant CRT was achieved in 12 patients (30.8%), while NCMR was found in 28 (82.4%). The median OS was 13.5 months in this group, 95% CI: 4.4-22.7 months. Conclusion. No statistically significant correlation was found between the 18 F-FDG metabolic response after the neoadjuvant CRT and histopathological response. Presently, the contribution of 18 F-FDG PET/CT as a marker of the potential result of CRT cannot be considered definite. Another study with a larger sample of patients and standardized algorithms for the examining protocols would be necessary for reaching definitive conclusions.

Changes in Total Lesion Glycolysis Evaluated by Repeated F-18 FDG PET/CT as Prognostic Factor in Locally Advanced Esophageal Cancer Patients Treated with Preoperative Chemoradiotherapy

“…In contrast to the current study and other published reports, some studies demonstrated that FDG-PET did not effectively correlate with tumor response and long-term survival in patients with LAEC undergoing neoadjuvant CRT [17,25,26]. Malik et al [25 ]explained the possible reason of these discordant results.…”

“…Several previous studies investigated the predictive and prognostic role of sequential F-18 FDG PET/CT for metabolic tumor response and survival in LAEC treated preoperatively by CRT and revealed conflicting results [17,18,19,20,21,22,23,24,25,26,27,28]. Most of these studies used the SUV max values for the prediction of metabolic response and survival in LAEC patients.…”

18F-fluorodeoxyglucose positron emission computed tomography for monitoring tumor response in esophageal carcinoma treated with concurrent chemoradiotherapy

“…As a semi-quantitative parameter of 18 F-FDG PET, SUV, which may reflect the intensity of metabolic activity of the tumor, has been suggested as a prognostic marker for the histopathological response of esophageal carcinoma (4)(5)(6)(7)(8)(17)(18)(19)(20). For example, Wieder et al (7) reported that, for histopathological responders, the decrease in SUV between baseline and 2 weeks after initiation of therapy was 44%, but was only 21% in the non-responders (P=0.0055).…”

Diffusion-Weighted Magnetic Resonance Imaging for Predicting and Detecting the Early Response to Chemoradiotherapy of Advanced Esophageal Squamous Cell Carcinoma

“…Several reports on determining the effect of CRT on esophageal carcinoma with F18-FDG PET have been published [26]. Similarly, it has reported that depending on the determination of the effect of CRT on other organs with DWMRI and tumor ADC increases in responders [15,16].…”