Application Of18F-FDG PET-CT In The Differential Diagnosis Of Gastrointestinal Lymphoma And Other Types Of Tumors

Research background:Gastrointestinal lymphoma is a special type of tumors in digestive system. The therapy is different from the others. It has an insidious onset, and the clinical symptoms are not special. It is easy to be misdiagnosis or missed diagnosis in previous examination. But the early diagnosis of tumors and the right stage determines the therapy, and affect the treatment’s effect. Since the18F-FDG PET-CT scan has been invented, it has been widely used in diagnosis of malignant tumor. It has obvious advantages in malignant tumor’s molecular diagnosis、staging and treatment decision-making. In the past, because the digestive system’s anatomic structure is special, the function of PET-CT is limited. Especially for the gastrointestinal lymphoma, the valuable of18F-FDG PET-CT scan is not very clear. objective:To determine the diagnostic role of18F-FDG PET-CT in gastrointestinal lymphoma and non-lymphoma malignant tumors.Materials and methods:The detailed history and clinicopathological characteristics of35patients with microscopically confirmed gastrointestinal lymphoma were collected retrospectively, particularly including the SUVmax of the lesions (primary tumor, lymph node metastasis and residual lesions post treatment). At the same time,40patients who were diagnosed pathologically as non-lymphoma maligant tumors in the same period were selected as control.of the possible difference of the maximal value of SUV among the gastrointestinal lymphomas or between the disease and other type malignant tumors were analyzed.Results:The mean of the18F-FDG PET-CT SUVmax for patients with gastrointestinal lymphoma was14.66, which was significantly higher than that (7.60) for patients with other types of gastrointestinal tumors (P<0.05). Moreover, the mean SUVmax for patients with DLBCL was16.73,which was also significantly higher than the value of7.61for patients with other types of lymphoma (P<0.05). Conclusion:The18F-FDG PET-CT is a helpful tool in the differential diagnosis of gastrointestinal lymphoma(especially for DLBCL),and it should be further investigated.