Primary gastric lymphoma: a clinical and therapeutic evaluation of 82 patients

Primary lymphoma of the colon

Primary lymphoma of the colon is a rare tumor of the gastrointestinal (GI) tract and comprises only 0.2-1.2% of all colonic malignancies. The most common variety of colonic lymphoma is non-Hodgkin's lymphoma (NHL). The GI tract is the most frequently involved site, accounting for 30-40% of all extra nodal lymphomas, approximately 4-20% of which are NHL. The stomach is the most common location of GI lymphomas, followed by the small intestine. Early diagnosis may prevent intestinal perforation; however, the diagnosis is often delayed in most cases. Therapeutic approaches described in two subsets include: Radical tumor resection (hemicolectomy) plus multi-agent chemotherapy (polychemotherapy) in early stage patients, biopsy plus multidrug chemotherapy in advanced stage patients. Radiotherapy is reserved for specific cases; surgery alone can be considered as an adequate treatment for patients with low-grade NHL disease that does not infiltrate beyond the sub mucosa. Although resection plays an important role in the local control of the disease and in preventing bleeding and/or perforation, it rarely eradicates the lymphoma by itself. Those with limited stage disease may enjoy prolonged survival when treated with aggressive chemotherapy.

The importance of endoscopic ultrasonography in the management of low-grade gastric mucosa-associated lymphoid tissue lymphoma

BACKGROUND

Anti-Helicobacter pylori therapy has been reported to cause regression of low-grade gastric mucosa-associated lymphoid tissue lymphoma in a high percentage of patients. However, in some patients, these lesions persist despite antibiotic treatment.

AIM

To determine the various endosonographic findings that may predict the regression of low-grade gastric mucosa-associated lymphoid tissue lymphoma post-antibiotics.

METHODS

Seventy-six patients with Helicobacter pylori-positive gastric mucosa-associated lymphoid tissue lymphoma were studied. Follow-up data were available on 51 patients. All patients were treated with antibiotics. Participants underwent pre- and post-anti-Helicobacter pylori therapy endoscopy with gastric biopsies, followed by endoscopic ultrasonography examination of the stomach.

RESULTS

Helicobacter pylori was eradicated in 45 of 51 (88%) patients. At the 2-year follow-up, complete regression of mucosa-associated lymphoid tissue lymphoma was seen in 28 of 51 (55%) patients: 12 of 16 (75%) patients in stage T1m N0, 11 of 19 (58%) patients in stage T1sm N0, four of eight (50%) patients in stages T1m N1 and T1sm N1, and one of four (25%) patients in stage T2 N0. None of the stage T2 N1 patients achieved clinical regression.

CONCLUSIONS

Endoscopic ultrasonography evaluation of gastric mucosa-associated lymphoid tissue lymphoma plays a pivotal role in the initial staging and post-treatment follow-up evaluation of these lesions. Accurate staging is essential in the determination of the optimal treatment modality.

Low-grade MALT lymphoma of the stomach: a review of treatment options

PURPOSE

Low-grade mucosa-associated lymphoid tissue (MALT) lymphoma of the stomach (MLS) is often associated with the presence of Helicobacter pylori (H. pylori) bacteria. Eradication of the infection with antibiotic therapy may result in regression of the lymphoma. But when antibiotic treatment fails to reverse the malignant process or if H. pylori is absent, other treatment options should be considered. Because MLS is often confined to the stomach and regional lymph nodes, it is potentially curable with local therapy. Endoscopy and improved imaging, with endoscopic ultrasound (EUS) and computerized tomography (CT), have reduced the prior dependence on surgery for diagnosis and staging of gastric lymphomas.

METHODS AND RESULTS

This review details the advances in the diagnosis, classification, and imaging of MLS. We also describe the experience that supports the use of radiation therapy as the preferred treatment of MLS in patients who have not responded to antibiotic therapy or have not had evidence for H. pylori infection.

CONCLUSIONS

Radiation therapy for MLS is not only effective and safe, but offers the significant advantage of low morbidity and gastric function preservation.

Gastric Lymphoma

The approach to the management of gastric lymphoma must begin with a precise pathologic diagnosis based on histologic examination and immunophenotyping, at a minimum. This should be followed by detailed staging procedures that include endoscopic ultrasonography (EUS). Most primary gastric lymphomas are low-grade Mucosa-Associated Lymphoid Tissue (MALT) or large-cell (high-grade) types. The treatments for these differ. For low-grade MALT lymphomas confined to the stomach, an attempt at eradication of Helicobater pylori is the first choice. If the patient does not have H. pylori, if eradication is unsuccessful, or if the disease stage is II1(E), radiation therapy is the next approach. Chemotherapy is the best option for disease that is stage II2(E) or higher and for disease that does not respond to antibiotics and radiation. Surgery should be reserved for patients with localized disease who do not respond to these other therapies. In patients with clinical stage I(E) large-cell lymphomas, there are valid arguments for and against the use of both surgery and stomach-sparing therapy. Surgery alone (if disease is pathologic stage I(E)) or surgery followed by chemotherapy (for disease that is pathologic stage II or higher) has more data defining expected outcomes. Recently published experience indicates that chemotherapy plus radiation therapy may be an acceptable alternative to surgery. The entire clinical picture and the patient's preferences must play a role in this difficult management decision. Chemotherapy is the clear first option in patients with disease that is stage II or higher. Local radiation therapy should be added in selected cases with residual local disease or bulky tumor.