EUS in the Evaluation of Gastric Wall Layer Abnormalities - Non-Hodgkin Lymphoma and Other Causes

A combination of upper endoscopy, abdominal ultrasound and computed tomography was used to stage gastric lymphoma before EUS. The advent of EUS has led to a marked improvement in accuracy in diagnosing and staging gastrointestinal lymphomas and LGF. Currently, EUS is regarded as the most accurate imaging modality for evaluation and staging of infiltrative gastric lesions. EUS allows a close and sharp visualization of the individual 5 layers of the gastric wall and an accurate assessment of peri-gastric structures and lymph nodes. The ability of EUS to accurately stage gastric lymphoma according to TNM system is of paramount importance as it allows to determine the best mode of therapy for the individual patient. In fact, although many therapies are now available for gastric MALT lymphoma, they cannot be randomly assigned to the patients. EUS makes the difference by helping to make the right choice. While early lesions, staged by EUS T1m and T1sm, may regress after anti-H. pylori therapy alone, more advanced lesions, staged by EUS from T2 to T4, usually require more aggressive treatment protocols. The importance of EUS lies not only in its ability to stage MALT lymphoma before treatment, but also in follow up as EUS may determine response to therapy and detect early relapse. At times, EUS may show restoration of normal gastric wall layers prior to evident histological remission, and at other times recurrent wall thickening or disruption may be seen in individuals who were previously in remission. For patients who persist to have a thickened gastric wall on EUS despite antibiotic therapy, other treatment modalities should be considered even if endoscopic biopsies are negative. In fact, these patients are likely to have persistent lymphoma.