Radiosensitization of sodium glycididazole in esophageal cancer evaluated by 18F-FMISO PET/CT

Objective To investigate the feasibility of sodium glycididazole (CMNa) on the radiosensitization of esophageal cancer (EC) by 18F-fluoromisonidazole (FMISO) PET/CT. Methods A total of 60 patients with EC from December 2016 to December 2017 were enrolled prospectively and were divided into control group (n=30; 21 males, 9 females; age: (56.6±10.0) years) and experimental group (n=30; 20 males, 10 females; age: (59.3±9.0) years) using completely randomized grouping design. Patients in the control group received radiotherapy alone, and those in the experimental group were treated with conventional radiotherapy and CMNa. All patients underwent 18F-FMISO PET/CT imaging 1 week before and after radiotherapy. The imaging results were visually and semi-quantitatively analyzed. The maximum standardized uptake value (SUVmax), tumor/muscle ratio (T/M), and hypoxia volume (HV) were calculated. Paired t test, two-sample t test and χ2 test were used to analyze the data. Results T/M and HV in the control group before and after radiotherapy were 3.92±0.57 vs 1.66±0.35, (1.84±0.31) vs (1.04±0.15) mm3, respectively; T/M and HV in the experimental group before and after radiotherapy were 4.01±0.68 vs 1.27±0.11, (2.01±0.22) vs (0.90±0.09) mm3, respectively. The primary tumor T/M, HV after radiotherapy in 2 groups were significantly lower than those before radiotherapy (t values: 12.15-24.43, all P<0.05) and the amplitudes of T/M and HV in the experimental group were significantly higher than those in the control group (ΔT/M: 2.77±0.60 vs 2.25±0.49, ΔHV: (1.12±0.18) vs (0.81±0.26) mm3;t values: 3.00 and 1.80, both P<0.05). Meanwhile, the local control rate of EC after 3 months in the experimental group was higher than that in the control group (80.0%(24/30) vs 53.3%(16/30); χ2=4.80, P<0.05). Conclusion CMNa has the radiosensitizing effect on EC and the 18F-FMISO PET/CT can evaluate the radiosensitization effect. Key words: Esophageal neoplasms; Radiotherapy; Radiation-sensitizing agents; Nitroimidazoles; Positron-emission tomography; Tomography, X-ray computed; Misonidazole