IS THE POLYMERASE CHAIN-REACTION OR CURE OF HELICOBACTER-PYLORI INFECTION OF HELP IN THE DIFFERENTIAL-DIAGNOSIS OF EARLY GASTRIC MUCOSA-ASSOCIATED LYMPHATIC TISSUE LYMPHOMA

Purpose: The differential diagnosis of early gastric mucosa-associated lymphatic tissue (MALT) lymphoma based on Helicobacter pylori gastrit is may be difficult when lymphoepithelial lesions are not detected. Th e aim of the present study was to investigate the question whether the polymerase chain reaction (PCR) or cure of H pylori infection may be of help in this respect. Patients and Methods: Twenty patients with su spected low-grade gastric MALT lymphomas were treated in a double-blin ded, randomized, crossover trial with 2,250 mg of either amoxicillin o r placebo, both in combination with omeprazole, for 14 days with the a im to cure H pylori infection. PCR was performed using primers specifi c for the CDR3 region to detect monoclonal B cells. Results: In five o f 20 patients, MALT lymphomas were finally diagnosed. Three of these f ive patients went into complete remission, while two were referred to surgery. In the 15 patients with gastritis, complete regression was ob served in all cases. With respect to PCR, monoclonal bands were detect ed in all four of the analyzed lymphoma patients before histology show ed lymphoma. In addition, monoclonal bands were found in three patient s with gastritis. In the patients with gastritis and monoclonal PCR, c omplete regression took longer as compared with the remaining 12 patie nts with polyclonal PCR and gastritis (P = .0209), Successful H pylori eradication was associated with earlier diagnosis of the MALT lymphom a (P = .0237). Conclusion: CDR3-PCR may be of help in the differential diagnosis of early gastric MALT lymphoma. Furthermore, H pylori eradi cation may lead to earlier diagnosis. (C) 1997 by American Society of Clinical Oncology.