Applications of diffusion-weighted MR imaging with background suppression in the diagnosis of gastrointestinal tumors and metastasis lymph nodes

Abstract

Objective To evaluate the diagnostic value of diffusion weighted MR imaging with background suppression(DWIBS) in gastrointestinal tumors and metastasis lymph nodes. Methods The preoperative diffusion weighted imaging with background suppression results in 11 patients with gastrointes-tinal tumors (including 6 gastric cancer patients,3 rectal cancer patients, 1 colon carcinoma patient and 1 anal canal cancer patient) were analyzed. The diagnostic ability to DWIBS for gastrointestinal primary tumors and the displaying ability to metastasis lymph nodes were evaluated. The ADC values of metastasis lymph nodes and non-metastasis lymph nodes in gastric cancer patients were measured and compared. Re-suits Among 11 patients,7 patients were diagnosed correctly by DWIBS,including 3 gastric cancer pa-tients(3/6),3 rectal cancer patients (3/3) and 1 anal canal cancer patient. The metastasis lymph nodes were displayod clearly in diffusion weighted imaging. The average ADC values of metastasis and non-metas-tasis lymph nodes in gastric cancer patients were (0.83±0.25)×10~(-3) mm~2/s and (1.61±0.29)×10~(-3) mm~2/s respectively and there was a significant statistical difference in these two groups (P<0.05).Conclusion Although DWIBS has a limited diagnostic ability to gastric primary tumors,there is a highly diagnostic value for primary tumors of rectal cancer, anal canal cancer and the metastasis lymph nodes of gastrointestinal tumors. Key words: Gastrointestinal neoplasms; Lymph nodes; Diffusion magnetic resonance imaging; Background suppression