Comparison of 3.0T and 1.5T magnetic resonance diffusion weighted imaging in the diagnosis of lymph node metastasis of gastric cancer / 肿瘤研究与临床

ABSTRACT

Objective To compare the diagnostic value of 3.0T and 1.5T magnetic resonance diffusion weighted imaging (DWI) in lymph node metastasis of gastric cancer. Methods Preoperative magnetic resonance examination was performed on 50 patients with gastric cancer by using Siemens 1.5T and 3.0T superconducting magnetic resonance imaging system, and the outcomes were compared with postoperative pathological results. The sensitivity, specificity and accuracy of the diagnosis in lymph node metastasis of gastric cancer were analyzed statistically. The apparent diffusion coefficient (ADC) values of lymph nodes were also evaluated for 1.5T and 3.0T magnetic resonance DWI. Results The sensitivity, specificity and accuracy of the diagnosis on lymph node metastasis of gastric cancer by 1.5T magnetic resonance DWI were 79.4 %, 81.4%and 80.0%, respectively, and the corresponding percentages of 3.0T magnetic resonance DWI were 84.6%, 79.7%and 83.1%. The accuracy rate of 3.0T magnetic resonance DWI was slightly higher than that of 1.5T in the diagnosis of lymph node metastasis of gastric cancer (χ2=5.451, P=0.020), but there were no significant differences in the sensitivity and specificity between the two groups (both P> 0.05). The accuracy rate of 1.5T magnetic resonance DWI in the diagnosis of lymph node metastasis of gastric cancer was less effective than that of the pathological diagnosis (χ2=7.410, P=0.007), but there was no significant difference between 3.0T magnetic resonance DWI and pathological diagnosis (χ2=2.450, P=0.120). The mean ADC values of metastatic and non-metastatic lymph nodes detected by 1.5T magnetic resonance DWI were (1.036 ±0.203) × 10-3 mm2/s and (1.476 ± 0.215) × 10-3 mm2/s (t= 6.813, P< 0.001), meanwhile, the corresponding values detected by 3.0T magnetic resonance DWI were (1.154 ± 0.183) × 10-3 mm2/s and (1.502 ± 0.264) × 10-3 mm2/s (t= 5.991, P< 0.001). The coincidence of the two methods for ADC value was favorable. Conclusions The diagnostic effect of 3.0T magnetic resonance DWI on lymph node metastasis of gastric cancer is better than that of 1.5T. ADC value provides a reliable imaging quantitative indicator for the determination of metastatic lymph nodes in gastric cancer, which plays a significant role in the clinical treatment options and prognosis of patients.