Comparison of the diagnostic value of miniprobe sonography system and conventional EUS combined with fine-needle aspiration for gastric lymphoma

Aim: To evaluate and compare the potential value of MPS, conventional EUS and EUS-FNA for diagnosis of gastric lymphoma during the follow-up investigations with treatment of radiation or chemotherapy.

Methods: The study was conducted from November 2009 to May 2010 and included a total of 22 patients confirmed as gastric lymphoma with pathology (MALT lymphoma and diffuse large B-cell lymphoma). All patients (12 men, median age 57 years, range 33–76 years) have a completive EUS procedure. According to 4 different characteristics of the gastric wall infiltration, combined with TNM classification, and 3 different changes of the gastric wall structure (retention, destruction, disappearance), peri-gastric lymphonodular involvement (hypoechogenicity, round shape, well-defined borders, diameter >1cm), we compare the staging and prognostic accuracy of different EUS techniques for gastric lymphoma and assess their clinical value.

Results: There are 4 endosonographic patterns of lymphoma infiltration: superficial-type (6, 27.3%), diffuse infiltrating-type (5, 22.7%), mass forming-type (9, 40.9%), mixed-type (2, 9.1%).

6 patients (46.2%) were staged as T1 and 7 patients (53.8%) were T2 by MPS, 7 patients (50%) were staged as T1 and 7 patients (50%) were T2 by EUS. The detection rate of peri-gastric lymphonodular involvement by EUS was higher than MPS (38% and 30%, respectively), and EUS showed clearer structure, but there was no statistically significant differences (P<0.05). During the term of follow-up, MPS and conventional EUS diagnosed 4 patients as recovery completely, the coincidence rate of diagnosis between EUS and pathology was 100%. And 9 patients were diagnosed as remission by EUS-FNA, the coincidence rate of diagnosis between EUS and cytology was 100%.

Conclusion: EUS has been considered as a safe and efficient technique in endoscopic examination. MPS can establish accurate condition of the gastric wall layers and infiltration of adjacent organs or tissues. The results of MPS are similar to the conventional EUS in the staging and prognosis of gastric lymphoma. Because of its simple equipment and convenient operation, MPS can be recommended as a regular part of follow-up investigations to predict the response of the lymphoma after the preserved treatment, such as radiation, chemotherapy, etc. Additionally, EUS-FNA has a high value for the diagnosis of gastric lymphoma, it should be performed in those patients with inconsistent treatment response or suspicious progress, especially for the patients with the echo poor infiltration of the third and fourth layer, or suspected peri-gastric lymphonodular. The cytology from EUS-FNA can improve the diagnostic accuracy of EUS.