Clinicopathologic characteristics and prognosis of Helicobacter pylori eradication-resistant gastric MALT lymphoma have not been well clarified. We analyzed a consecutive series of gastric MALT lymphomas at our institution regarding treatment, clinical course, and prognosis, with special reference to responsiveness to H. pylori eradication and presence of API2-MALT1.
Subjects were 92 consecutive patients with gastric MALT lymphoma. Seventy were H. pylori positive, and 87 received H. pylori eradication therapy. The remaining five cases were API2-MALT1 positive and did not receive eradication treatment. Second-line treatments were radiation therapy, total gastrectomy, and chemotherapy (rituximab, rituximab plus CHOP, or rituximab plus 2-chlorodeoxyadenosine).
Gastric MALT lymphoma was classified into three groups, except one case with API2-MALT1 who responded to H. pylori eradication therapy: responders without API2-MALT1 (group A, N = 56, 65%), nonresponders without API2-MALT1 (group B, N = 16, 19%), and nonresponders with API2-MALT1 (group C, N = 14, 16%). Most cases in group A attained complete remission (CR) in 2 or 3 months and CR persisted for an average of 51.1 months (3–134 months). Recurrence was only seen in one case. In groups B and C, radiation therapy, chemotherapy, and total gastrectomy resulted in CR in 13, 5, and 2 cases, respectively. In 5 group B patients and 6 group C patients who did not undergo second-line therapy, disease did not progress for an average of 10.4 and 40.1 months, respectively. In 1 group C case who did not receive second-line treatment, lymphoma metastasized to the lung 12 yr after eradication. All group B patients and all but 2 group C patients remain alive; one of these deaths was from gastric carcinoma developing 7 yr after eradication.
Gastric MALT lymphoma responding to H. pylori eradication demonstrated good prognosis, and for nonresponsive cases, second-line treatments resulted in CR. However, careful observation for development of gastric carcinoma and disease progression is essential during follow-up of API2-MALT1-positive MALT lymphoma when patients decline second-line treatment.
1Department of Endoscopy, Aichi Cancer Center Hospital, Nagoya, Japan, 2Division of Molecular Medicine, Aichi Cancer Center Research Institute, Nagoya, Japan, and 3Department of Pathology and Molecular Diagnosis, Aichi Cancer Center Hospital, Nagoya, Japan; 4Department of Pathology, Nagoya University, Nagoya, Japan
Reprint requests and correspondence: Tsuneya Nakamura, Department of Endoscopy, Aichi Cancer Center Hospital, Kanokoden 1-1, Chikusa-ku, Nagoya, 464-8681, Japan.
Received April 13, 2007; accepted July 16, 2007.
CONFLICT OF INTERESTGuarantor of the article: Tsuneya Nakamura, M.D., Ph.D.
Specific author contribution: Tsuneya Nakamura: Patient care, clinical data collection and analysis, writing paper. Masao Seto: API20-MALT1 analysis, array CGH, writing paper. Masahiro Tajika: Patient care, clinical data collection and analysis. Hiroki Kawai: Patient care, clinical data collection and analysis. Takio Yokoi: Pathological diagnosis.Yasushi Yatabe: Pathological diagnosis, API2-MALT1 analysis. Shigeo Nakamura: Pathological diagnosis, data analysis. All authors have approved the final draft of the manuscript.
Financial support: This study was supported by Grants-in-Aid from the Ministry of Health, Labor and Welfare; from the Ministry of Education, Culture, Sports Science and Technology; from the Japan Society for the Promotion of Science.
Potential competing interests: None.