In addition to Waldeyer's ring, the stomach is a common extranodal localization for malignant lymphomas. Among indolent lymphomas, marginal zone lymphomas dominate, other entities are more rare. For patients with marginal zone lymphomas with infection of H. pylori, triple treatment is considered standard treatment in Norway as long as guidelines are followed for diagnostics, treatment, and follow-up. Aggressive stomach lymphomas constitute most mantel cell lymphomas, diffuse giant cell lymphomas and Burkitt's lymphoma. Serious bleeding and/or massive invasion to serosa with danger of perforation are considered for a stomach resection or gastrectomy as a primary measure after consultation between oncologist and surgeon.
Curative radiation therapy
- Patients with marginal zone lymphoma stage PeI
- Without H. pylori infection
- Patients who cannot or do not wish to follow the recommended follow-up schedule for eradicative treatment.
- Unfavorable cytogenetic aberrations or a thickened stomach wall are also possible grounds for primary radiation therapy.
- Patients with marginal zone lymphoma also in regional lymph nodes (stage Pe II1)
- Patients without effect of or with local recurrence after eradicative treatment.
- Other forms of indolent stomach lymphomas in stages Pe l and Pe ll1
- If primary surgery is completed for indolent stomach lymphoma and the surgery is radical, no additional treatment is given for stage PeI. If there is residual lymphoma in the stomach or involvement of regional lymph nodes (stadium Pe II1), supplementary radiotherapy is given to residual areas and regional lymph nodes.
- Aggressive lymphomas in the stomach are treated from protocols for their respective histology. Diffuse giant cell B cell lymphoma stages Pe I-Pe II1 are treated as desribed for DLBCL stage I/II. Three to six CHOP-based cycles followed by radiation therapy with 2 Gy x 20 (40 Gy) are given. Stages Pe II2- IV are treated as advanced disease of DLBCL and supplementary radiotherapy is considered for any residual lesions. Mantel cell lymphomas are treated analagous to DLBCL with suitable chemotherapy followed by radiotherapy, or are considered for inclusion of ongoing protocols. Burkitt's lymphoma is treated from the GMALL-NHL-2002 protocol where radiotherapy to the stomach may be appropriate after chemotherapy.
Palliative radiation therapy
- For palliative radiotion therapy, the method normally follows the same guidelines as the curative plan with individual modifications.