Clinicopathological features of gastric mucosa associated lymphoid tissue (MALT) lymphomas: high grade transformation and comparison with diffuse large B cell lymphomas without MALT lymphoma features

Abstract

Aims-To investigate the clinicopathological diVerences among gastric low grade MALT lymphomas (low MALT), large B cell lymphomas with low grade components (secondary high grade MALT lymphomas, high MALT), and diVuse large B cell lymphomas without low grade features (primary high grade MALT lymphomas, DLL). Methods-Clinicopathological and morphological characters of 126 gastric lymphoma cases were studied: 82 cases of low MALT lymphoma including 40 that were surgically resected, 17 cases of high MALT lymphoma including 13 surgically resected, and 27 cases of DLL including 12 surgically resected. Results-Age ranges were as follows: low MALT lymphoma, 34 to 85 years (mean 59.9); high MALT lymphoma, 53 to 88 years (mean 68.5); DLL, 29 to 83 years (mean 62.3). The average age for low and high MALT lymphomas was significantly diVerent (p < 0.05), but there were no differences in other comparisons. There was a female predominance of low MALT lymphoma patients (female to male ratio, 47/35), while for high MALT patients the ratio was almost even (8/9), and for DLL patients there was a male predominance (11/16). Examination of surgically resected material showed that MALT lymphomas had a wider distribution in the gastric wall than DLL. Conclusions-The findings suggest that at least some of the high grade gastric lymphomas, especially in patients younger than the fifth decade, do not originate from high grade transformation of low MALT lymphomas. It seems to take about one decade at least for high grade transformation of low MALT lymphomas.

Helicobacter pylori and carcinogenesis of gastric B‐cell lymphomas

“…Regression results suggest that more steps are required for the development of marginal zone B‐cell lymphoma ( m = 5.7) than for the carcinogenesis of diffuse large B‐cell lymphoma ( m = 4.2). This interpretation of our results supports the hypothesis that MZBL and DLBL may have different lines of development as suggested by the findings of Yoshino et al 23. in contrast to the hypothesis that MZBL precedes DLBL 10.…”

Clinical characteristics of primary gastric lymphoma detected during screening for gastric cancer in Korea

“…Although several previous studies reported that PGLs affect men more often than women, this seems because they included symptomatic patients who visited the hospital, and consequently in those studies, DLBCL and MALT lymphoma were common types of PGL like the outpatient group of our study. This is compatible with previous report from Japan where gastric MALT lymphoma showed female predominance, while high‐grade gastric lymphoma showed male predominance . Second, gastric adenocarcinoma developed less frequently in middle‐aged women than middle‐aged men or elderly people.…”

Clinicopathologic features of surgically resected primary gastric lymphoma

“…Cabras et al [16] advocated multiple pathways to high grade transformation. The time taken for high grade transformation was estimated at about 10 years by Yoshino et al [17] , which was not definite with our study. On the other hand, there were 4 cases in our study who had been diagnosed as low grade MALT lymphoma by preoperative gastroscopy, and they were diagnosed as higher grade lymphoma after H pylori eradication or surgery.…”