Abstract 4219
Background
The eradication of Helicobacter pylori (HPE) using antibiotics is successful in around 70% of patients with gastric mucosa-associated lymphoid tissue lymphoma (MALToma). However, the role of antibiotics in the first-line treatment of extragastric MALToma remains unclear. Previous studies suggested that HP can be detected in extragastric mucosa areas. In this study, we aimed to assess whether first-line HPE is effective in the treatment of early-stage extragastric MALToma.
Methods
Since February 2016, we started a prospective phase II trial of first-line HPE in treating localized extragastric MALToma. All patients received sequential HPE regimen, consisting of lansoprazole 30 mg and amoxicillin 1 g for the first 7 days, followed by lansoprazole 30 mg, clarithromycin 500 mg, and metronidazole 500 mg for another 7 days; with all drugs given twice daily. Before HPE, patients received examination of HP, including 13C urea breath test and serology (gastric biopsy for histology and rapid urease test, optional).
Results
This study enrolled 19 patients with extragastric MALToma (9, conjunctiva; 3, orbit; 3, parotid gland; 2, lung; 1, nasopharynx; 1, skin). There were 7 men and 12 women, with a median age of 50 years old (range 33-90). We observed an antibiotic response (complete remission [CR], number = 5; partial remission [PR], number = 5) in 10 (52.6%) out of 19 patients. The response rates (CR and PR) for patients with stages IE and IIE1 tumors were 60.0% and 44.4%, respectively (P = 0.656). The median time to CR after the completion of antibiotic therapy in all 5 patients was 5.0 months. We found that the presence of HP infection was observed in 6 (60.0%) of 10 antibiotic-responsive cases, but 2 (22.2%) of 9 antibiotic-unresponsive cases had HP infection (P = 0.170). After a median follow-up of 20.20 months, 5 patients with CR remained lymphoma-free and alive, however, one patient with initial PR of nasopharyngeal MALToma experienced tumor progression 6 months later.
Conclusions
A substantial portion of patients with localized extragastric MALToma responded to first-line HPE. Further investigation of the underlying mechanisms of bacteria in the lymphomageneis of extragastric MALToma is warranted.
Clinical trial identification
NCT02987127 (Study Start Date: February 2016).
Legal entity responsible for the study
National Taiwan University Hospital.
Funding
Ministry of Health and Welfare (grant number: MOHW107-TDU-B-211-123002).
Editorial Acknowledgement
Disclosure
All authors have declared no conflicts of interest.