Predictive value of endoscopic ultrasonography for regression of gastric low grade and high grade MALT lymphomas after eradication of Helicobacter pylori

Abstract

Background: While a close association between gastric mucosa associated lymphoid tissue (MALT) lymphoma and Helicobacter pylori infection has been established, there are still cases which do not respond to H pylori eradication.

Aims: To investigate the clinicopathological factors which may help predict the therapeutic efficacy of H pylori eradication in gastric MALT lymphoma.

Patients: Forty one patients with gastric MALT lymphoma, including low and high grade lesions.

Methods: After endosonographic staging was determined, H pylori was eradicated in all patients, and the subsequent gastric pathological course was then investigated.

Results: Complete regression of MALT lymphoma was observed in 29(71%) patients, partial regression in five (12%), and no regression in seven (17%). Twenty six (93%) of 28 MALT lymphomas restricted to the mucosa but only three (23%) of 13 lymphomas which invaded the deep portion of the submucosa or beyond completely regressed. Kaplan-Meier analysis for the probability of complete regression of MALT lymphoma revealed a significant difference between tumours restricted to the mucosa and those invading the submucosa deeply or beyond (p<0.05). Neither the presence of a high grade component, perigastric lymphadenopathy, nor clinical staging prior to eradication correlated with the probability of lymphoma regression.

Conclusions: Assessment of deep submucosal invasion by endosonography is valuable for predicting the efficacy of H pylori eradication in gastric MALT lymphoma.

Figure 1

Pretreatment endoscopic ultrasonographic images of gastric mucosa associated lymphoid tissue (MALT) lymphomas. (A) A 43 year old man showed low grade MALT lymphoma, without any evidence of a high grade component, restricted to the mucosa with no significant submucosal invasion. (B) A 68 year old woman showed a high grade MALT lymphoma with a low grade component invading the deep portion of the submucosa. (C) A 62 year old man showed high grade MALT lymphoma with a low grade component invading the muscularis propria. (D) A 72 year old male patient showed high grade MALT lymphoma with a low grade component involving the serosa.

Figure 2

A 68 year old female case of high grade mucosa associated lymphoid tissue (MALT) lymphoma with a low grade component in stage EII, deeply invading the submucosa, which regressed after eradication therapy. (A) Pretreatment endoscopic ultrasonography demonstrates enlargement of many perigastric lymph nodes. (B) Pretreatment endoscopy reveals multiple polypoid lesions with a central erythematous depression in the corpus and fundus. (C) The histological picture shows both a high grade component of large centroblast-like cells (right) and a low grade component of small centrocyte-like cells (lower left). (D) A follow up endoscopic view four months after the start of eradication therapy showing regression of the lymphomatous masses in the corpus and fundus.

Figure 2

A 68 year old female case of high grade mucosa associated lymphoid tissue (MALT) lymphoma with a low grade component in stage EII, deeply invading the submucosa, which regressed after eradication therapy. (A) Pretreatment endoscopic ultrasonography demonstrates enlargement of many perigastric lymph nodes. (B) Pretreatment endoscopy reveals multiple polypoid lesions with a central erythematous depression in the corpus and fundus. (C) The histological picture shows both a high grade component of large centroblast-like cells (right) and a low grade component of small centrocyte-like cells (lower left). (D) A follow up endoscopic view four months after the start of eradication therapy showing regression of the lymphomatous masses in the corpus and fundus.

Figure 3

Kaplan-Meier analysis of the probability of having complete regression of gastric mucosa associated lymphoid tissue lymphoma by the indicated time in patients with tumours restricted to the mucosa and in those with tumours invading the deep portion of the submucosa or beyond (log rank test, p<0.05).