P0214 - A Rare Case of Regression of Rectal MALT Lymphoma After Eradication of Helicobacter pylori

Jamil M. Shah, MD, Eric O. Then, MD, Manan A. Jhaveri, MD, Ali Aamar, MD, Evangelos Tsipotis, MD, Yingxian Liu, MD, Derrick Cheung, MD, Madhavi Reddy, MD, FACG
Brooklyn Hospital Center, Brooklyn, NY

Introduction: Generally, lymphomas originate from lymph nodes. However, malignant lymphocytes can infiltrate in sites other than lymph nodes, referred to as extranodal involvement. Almost any organ can be affected, but extranodal lymphoma involving the rectum is rare. Moreover, among GI lymphomas, primary rectal lymphoma (PRL) comprises less than 1%. Among rectal malignancies, it is the third most common after adenocarcinoma (90-95%) and carcinoid (5%). The most common variant of PRL is the mucosa-associated lymphoid tissue (MALT) type. Here, we present a rare case of regression of rectal MALT lymphoma after H. pylori eradication.

Case Description/Methods: A 74-year-old woman, with PMH of HTN, underwent colonoscopy for surveillance of tubular adenoma. A total of six sessile polyps, ranging in size from 5 mm to 1 cm, were removed (Fig 1A). Biopsy of the rectal polyp showed extranodal marginal zone lymphoma of MALT-type (Fig 1B). Subsequently, EGD was performed and showed H. pylori-associated gastritis. She was treated with an amoxicillin, clarithromycin, and PPI-based regimen, and, four weeks after completion of treatment, repeat H. pylori stool Ag test was negative. After discussion between her Oncologist and Gastroenterolgist, it was recommended to repeat a colonoscopy for surveillance in 6 months, given suspected rectal MALT lymphoma. Ultimately, colonoscopy showed an 8 mm subepithelial nodular lesion in the rectum. Biopsies were not taken as she was planned for EUS evaluation and polypectomy based on EUS findings. The rectal EUS showed a 6.4 x 4.6 mm lesion arising from the muscularis mucosal layer in the rectum. The submucosal layer appeared intact. Then, it was removed en- bloc with EMR (Fig 1C). Biopsy showed benign colonic mucosa with prominent lymphoid follicles, but no evidence of lymphoma.

Discussion: For gastric MALT lymphoma, H. pylori eradication therapy is recognized as an effective treatment. Conversely, for rectal MALT lymphoma, H. pylori eradication therapy is controversial. Several reports, including ours, document the disappearance of rectal MALT lymphoma after H. pylori eradication. Nevertheless, due to its rarity, the analysis of outcomes of various therapeutic approaches remains difficult. Currently, there is no standardized therapy, and the best treatment modality continues to be debated. Further investigation is needed.


Figure: Figure 1A. Image from initial colonoscopy. A 1 cm sessile polyp, one of six total sessile polyps removed during colonoscopy, was found in the rectum. This polyp was removed by snare cautery polypectomy. 1 hemoclip was applied to prevent delayed bleeding.

Figure 1B. H&E 40x: MALT lymphoma of the rectum. The neoplastic cells are derived from the marginal zone of reactive non-neoplastic lymphoid follicles. These cells then disperse to the adjacent lamina propria.

Figure 1C. Image from subsequent surveillance colonoscopy. A 7 mm subepithelial nodule was found in the rectum, and removed en- bloc with endoscopic mucosal resection (EMR). Biopsy results would show benign colonic mucosa with prominent lymphoid follicles, but no evidence of lymphoma.


Disclosures:
Jamil Shah indicated no relevant financial relationships.
Eric Then indicated no relevant financial relationships.
Manan Jhaveri indicated no relevant financial relationships.
Ali Aamar indicated no relevant financial relationships.
Evangelos Tsipotis indicated no relevant financial relationships.
Yingxian Liu indicated no relevant financial relationships.
Derrick Cheung indicated no relevant financial relationships.
Madhavi Reddy indicated no relevant financial relationships.


Jamil M. Shah, MD, Eric O. Then, MD, Manan A. Jhaveri, MD, Ali Aamar, MD, Evangelos Tsipotis, MD, Yingxian Liu, MD, Derrick Cheung, MD, Madhavi Reddy, MD, FACG. P0214 - A Rare Case of Regression of Rectal MALT Lymphoma After Eradication of Helicobacter pylori, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.