Antibiotic treatment as sole management of Helicobacter pylori-negative gastric MALT lymphoma: a single center experience with prolonged follow-up.

ABSTRACT

Relatively little is known about the long-term outcome of patients with Helicobacter pylori (HP)-negative gastric lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) with antibiotic therapy as sole management. We have analyzed all patients with HP-negative gastric MALT lymphoma undergoing antibiotic therapy as sole management of their disease. HP negativity was defined as negative histology, breath test and serology, and response to treatment, survival and long-term outcome was assessed together with clinico-pathological characteristics including t(11; 18) (q21; q21) translocation. Out of 97 patients with gastric MALT lymphoma, 24 were HP-negative, and 13 (5 females and 8 males) underwent only antibiotic management for initial therapy. Eight had stage I and five were found to have stage II disease, with three patients suffering from an underlying autoimmune disease. Antibiotic therapy consisted of standard HP eradication regimens consisting of clarithromycin in all patients, along with metronidazole in seven and amoxicillin in six plus a proton-pump inhibitor. After a median follow-up of 95 months (42-, 181+), 12/13 patients are alive. Six patients with stage I disease achieved an objective response (five complete (CR) and one partial remission, 46 %), four had stable disease (lasting 11-27 months), and three progressed. All patients with stable disease received chemotherapy, but only one patient due to clear cut progression. One patient relapsed 23 months after initial CR, and achieved a second CR with antibiotics now lasting 87 months. These results indicate that a relevant percentage of patients with HP-negative gastric MALT lymphoma may benefit from antibiotic therapy and do not require additional oncological therapies. Our data suggest that the remissions seen in these patients might be durable as evidenced by prolonged follow-up in our series.