Long-term results of stomach-conserving therapy in gastric MALT lymphoma.

Abstract

To evaluate long-term results of stomach-conserving therapy and to assess the value of histological probable minimal residual disease (pMRD) in predicting outcome in patients with gastric MALT lymphoma. We studied 115 patients with stage I-II(2) gastric MALT lymphoma treated between 1975 and 2002. Initially, first-line treatment consisted of radiotherapy only. Since 1994 most patients were primarily treated with Helicobacter pylori eradication; radiotherapy was used in case of eradication failure. To assess the value of pMRD, first follow-up biopsy samples classified as compete remission (CR) according to classical clinico-pathological criteria and biopsy samples 1 year after assessment of histological CR were reviewed; results were related to outcome. Following radiotherapy only (n=56) 96% achieved a clinical CR; 10-year cancer-specific survival rate was 94%. Following H. pylori eradication only (n=35) CR-rate was 43% and after additional treatment 89%; 5-year cause-specific survival was 93%. There was no difference in relapse rate following initial histological CR or pMRD. Patients with early stage gastric MALT lymphoma have a favorable long-term outcome following conservative treatment. Outcome after H. pylori eradication followed by delayed radiotherapy on indication was excellent. In our series pMRD was not associated with increased risk of recurrence.