PB2021 GASTRIC MUCOSA‐ASSOCIATED LYMPHOID TISSUE LYMPHOMA: A MONOCENTRIC EXPERIENCE

Abstract

Background:Mucosa‐associated lymphoid tissue (MALT) lymphoma accounts for 7‐8% of B‐cell lymphoma. Tumor proliferation consists of type B lymphomatous cells of low grade malignancy. They are considered indolent and are part of the marginal zone. They constitute the predominant histological type of non‐Hodgkin's malignant lymphoma of the stomach. Transformation into high‐grade lymphoma is rare.Aims:The aim of this study is to describe the clinical characteristics and the therapeutic results of MALT lymphoma.Methods:We reviewed retrospectively the records of 18 patients presenting with gastric MALT lymphoma treated between 1993 and 2018. Patients with low‐grade lymphoma in failure after helicobacter eradication had exclusive gastric external radiotherapy. Chemotherapy were indicated in case of high grade lymphoma transformation. Radiotherapy doses range between 30 and 40 Gy (2 Gy per fraction, five fractions per week).Results:Median age was 52 years old. All tumours were IE stage. Helicobacter pylori was positive in 15 cases. Three patients had other cancers (gastric adenocarcinoma, breast cancer, mantle lymphoma). All patients received antibiotic therapy (triple therapy in 12 cases and concomitant treatment in 7 cases) with responding residual disease in 6 cases and probable minimal residual disease in 9 cases. Second line antibiotherapy was pylera in 3 cases and levofloxacin with amoxicillin in 2 cases. Seven patients with low‐grade MALT lymphoma had radiotherapy. Four patients with high‐grade transformed lymphoma received chemotherapy. Seventeen patients are in complete remission after treatment achievement. Five and 10‐ year disease‐free survival are 100%.Summary/Conclusion:Eradication of Helicobacter pylori is the mainstay of treatment of gastric MALT lymphoma. The levocine‐amoxicillin combination with proton pump inhibitor seems to be effective as a second‐line treatment in case of non availability of the pylera. External irradiation is an effective and well‐tolerated treatment modality in case of resistance to helicobacter eradication. Immuno‐chemotherapy is indicated for diffuse lymphoma (stage III and IV) or in case of transformation into large cell lymphoma.