[Radiotherapy of MALT-lymphoma of the stomach]

The stomach is the most common extranodal site of the low-grade MALT lymphoma. This lymphoma usually appears in elderly patients, with typically indolent signs. At the time of the diagnosis, the lymphoma is usually localized in the stomach and/or the adjacent lymph nodes. The choice in these cases is local treatment, which in the past involved only a surgical approach (total/partial gastrectomy), whereas more recently radiotherapy is preferred.

The radiation fields cover the whole stomach and the paragastric lymph nodes. The radiation doses range from 30 to 40 Gy, given in 1.5 Gy fractions 5 days a week. An adequate dose distribution to the target volume can be achieved by 3D treatment planning and conformal irradiation.

At our institute, 5 patients were treated with this method, the intention was curative in 3 cases, and palliative in 2 cases. The median dose in the 4 cases completed as initially planned was 33.6 Gy, delivered at 1.5 Gy per fraction. The adjacent critical organs do not exceed the tolerance doses by this method.

In these 4 cases, complete regression was achieved, as determined by endoscopy and biopsy. In the fifth, locally advanced case, irradiation had to be terminated because of gastric bleeding. During irradiation, no other severe acute side-effects were detected.

The literature and our preliminary results confirm that radiation therapy for early, localized MALT lymphoma of the stomach, or in disseminated cases, can be not only effective and safe, but offers the significant advantages of low treatment-related morbidity and preservation of the gastric function.