Outcome of Radiotherapy for Gastric Mucosa-Associated Lymphoid Tissue Lymphoma Refractory to Helicobacter Pylori Eradication Therapy

Abstract

Most low-grade gastric mucosa-associated lymphoid tissue (MALT) lymphomas respond to eradication of H. pylori, however, some are refractory. The effectiveness of radiotherapy for MALT lymphoma refractory to H. pylori eradication has been demonstrated. However, the long-term outcome and associated late radiation morbidity of radiotherapy for gastric MALT lymphoma are unclear. We evaluated the efficacy of radiotherapy and the radiation-associated adverse effects for gastric MALT lymphoma refractory to H. pylori eradication therapy. Eighteen patients with H. pylori-positive gastric MALT lymphoma received H. pylori eradication therapy, of which three patients refractory to eradication of H. pylori were subsequently treated with irradiation (median 39 Gy, range 36-40 Gy). Efficacy of radiotherapy and associated radiation morbidity were evaluated. Adverse events were evaluated according to RTOG and NCI-CTC criteria. Radiation was well tolerated. All three patients treated with radiotherapy achieved complete remission, which was sustained for a median follow-up period of 42.0 months (range, 24-72 months). As acute radiation side effects, all patients experienced mild nausea (Grade 1 by RTOG and 1 point [1 category] in NCI-CTC). One patient had Grade 1 appetite loss. There were no severe late adverse events. One patient had left kidney atrophy of approximately 10%, but none had renal dysfunction. Radiotherapy for patients with gastric MALT lymphoma refractory to H pylori eradication was effective without any critical acute or late adverse events.