Endoscopic mucosal resection and cure for rectal mucosa-associated lymphoid tissue lymphoma

Abstract

We present a case of Helicobacter pylori–negative rectal mucosa-associated lymphoid tissue (MALT) lymphoma found on colonoscopy done for colorectal cancer screening. The lesion was successfully removed with endoscopic mucosal resection alone, without concomitant antibacterial treatment. On surveillance exams, the patient has had a 5-year disease-free survival. While prior reports highlight use of multiple modalities, this is the only case we are aware of in which treatment with endoscopic mucosal resection alone without antimicrobial therapy led to disease-free survival at 5 years.

While gastric mucosa-associated lymphoid tissue (MALT) lymphoma can be seen in patients infected by Helicobacter pylori, extragastric MALT can be seen in those without infection. Antimicrobial therapy is standard of care for treatment for H. pylori–associated MALT lymphoma. Rectal MALToma has been treated with radiation, antibiotics, and combination therapies. We report our experience with treatment using endoscopic mucosal resection (EMR) alone without antimicrobial therapy with disease-free survival at 5 years.

CASE PRESENTATION

A 72-year-old white man was initially evaluated for a screening colonoscopy. He was asymptomatic, with no weight loss, bleeding, or adenopathy. He had known hypertension, hyperlipidemia, and short segment Barrett’s esophagus without dysplasia but no family history of neoplasia. Colonoscopy 10 years earlier showed generalized diverticulosis. Endoscopy 4 years earlier showed Barrett’s esophagus, without H. pylori on gastric biopsies.

At the time of diagnosis, a 2-cm raised, erythematous area in the mid rectum was biopsied (Figure 1a) and revealed a low-grade B-cell lymphoma. Positron emission tomography was normal. EMR of the lesion was performed. Pathology was consistent with a rectal MALT lymphoma, demonstrating a dense lymphoid infiltrate with a positive immunohistochemical stain for CD20. The margins of the resection were clear of lymphoid involvement. Follow-up proctoscopy 4 months later identified a tattooed scar with no histologic evidence of lymphoproliferative disorder recurrence. Colonoscopy 5 years after resection revealed no disease recurrence (Figure 1b).

Figure 1.

(a) Rectal erythema from index colonoscopy. (b) Tattooed rectum showing no recurrence of disease 5 years after endoscopic mucosal resection.

DISCUSSION

In MALT lymphoma, first described by Isaacson and Wright in 1983, marginal zone B cells undergo malignant transformation.^1,2 Rectal MALToma accounts for <1% of colorectal malignancies.³ Occurrence may exist in sites of acquired or physiologic inflammation in the setting of infection or autoimmune pathology, such as Sjogren’s disease or Hashimoto’s thyroiditis.^1,3 The most common location in the gastrointestinal tract is the stomach; there, MALTomas account for 50% to 70% of gastric lymphomas.^1,4 As H. pylori is associated with the development of gastric MALT lymphoma, eradication is generally the first-line treatment, with remission in 85% of patients.^1,5 Yet, there does not appear to be a relationship between H. pylori and extragastric MALT lymphoma, which limits treatment options.⁶ Studies suggest that other microorganisms may be involved, such as Campylobacter jejuni in the small intestine, Chlamydia psittaci in orbital lymphoma, and Borrelia burgdorferi in cutaneous lymphoma.¹

Treatment of extragastric MALToma traditionally includes H. pylori treatment or combination chemotherapy, radiation, and surgery.^3,4,7 Surgical resection is possible in localized colorectal MALT lymphoma tumors, as many are found before they metastasize. Combination therapy with antimicrobials and external beam radiotherapy has been reported in patients with and without gastric H. pylori, with disease-free survival up to 6 years.^1,8,9 Surgery and adjuvant chemotherapy have good outcomes and disease-free survival of up to 2 to 4 years.^3,10

Primary EMR has been utilized for H. pylori–negative patients who were treated with triple therapy despite no pathologic evidence of infection.¹¹ Two prior case reports described snare polypectomy and EMR for colorectal MALT lymphoma without evidence of recurrence.^12,13 Curative resection for esophageal MALT lymphoma with endoscopic submucosal dissection has also been reported.¹⁴ EMR as monotherapy, as well as in combination with radiation therapy, has been used for stage I to IV disease with good survival.¹⁵

To our knowledge, this is the only documented case of H. pylori–negative primary rectal MALT lymphoma treated with EMR alone that had a disease-free survival of >5 years. Stage I disease limited to the gastrointestinal tract can be treated successfully with EMR monotherapy.