Purpose: Mucosa-associated lymphoid tissue (MALT) lymphoma is a distinct disease with specific clinical and pathologic features that may affect diverse organs. We analyzed our recent experience with Stage I/II MALT lymphoma presenting in the stomach and other organs to assess the outcome following radiation therapy (RT) alone.
Patients and methods: Forty-one patients with Stages I (37) and II (4) disease were treated between 2000 and 2006. Patients with transformed MALT were excluded. The median age was 60 years (range, 25-86 years), male: female ratio 1:1. Presenting sites included stomach, 11; orbital adnexa, 21; thyroid, 1; other head and neck, 3; small bowel, 3; skin, 1; and rectum, 1. Thirty-five patients (85%) received RT-alone and 6 (15%) received antibiotics followed by RT. RT dose was 30Gy in 20 fractions (fr) in all 41 patients. Mean follow-up time was 32.0 months (range, 2.1-162 months).
Results: A first complete response was achieved in all 41 patients. Only one patient died from bile duct carcinoma at 22 months from the start of irradiation for conjunctiva MALT lymphoma without recurrence of lymphoma. The other 40 patients were alive. Thirty-eight patients out of them were alive without recurrence. One patient with a duodenal lymphoma had a recurrence in non-irradiated distant sites at 1 month. Another patient with a bilateral eye lid lymphoma had a recurrence within radiation field at 41 months. The absolute local control rate with radiation was 98% (40/41 patients).
Conclusion: Localized MALT lymphomas have excellent prognosis following moderate-dose RT (30Gy/20fr).