Small Bowel Lymphoma.

Treatment of small bowel lymphoma requires the expertise of medical and surgical subspecialists. The two most important factors that determine the optimal treatment are histology and staging of small bowel lymphoma. Other factors that may affect treatment include age, multiple areas of involvement, tumor size, and perforation. At present, the best treatment for gastrointestinal lymphoma (stage IE disease) is limited resection of the tumor, followed by postoperative radiotherapy. The cure rate is approximately 75% for stage IE patients, even for those with aggressive histologic types. Chemotherapy is reserved for advanced-staged tumors. In patients with regional nodal involvement or extranodal involvement confined to one side of the diaphragm (pathologic stage IIE disease), chemotherapy should be combined with radiation therapy. The best chemotherapy regimen depends on the histology of the tumor. For diffuse large B-cell lymphoma, the most frequently diagnosed subtype of non-Hodgkin's lymphoma (NHL), the CHOP regimen (cyclophosphamide, doxorubicin, vincristine, and prednisone) is still the gold standard. Clinical trials have been conducted evaluating the new monoclonal antibody rituximab, along with the CHOP regimen for primary NHL. Results have been promising. The use of rituximab in the treatment of extranodal lymphoma is still being evaluated. Low-grade lymphomas have a more indolent course and do not respond as well to combination chemotherapy agents as the high-grade tumors. Fludarabine alone or in combination with cyclophosphamide is effective as a first-line agent for patients with low-grade NHL. It has also been used to treat relapsed or refractory low-grade NHL. Some promising results have been reported using the chemoimmunotherapy agent rituximab alone or in combination with fludarabine for the treatment of low-grade NHL. However, clinical trials are still needed. In patients with nodal involvement on both sides of the diaphragm or other extranodal involvement such as bone marrow or liver (pathologic stages IIIE and IVE), the disease is managed primarily with combination chemotherapy. Radiation therapy is reserved for treatment of initially bulky tumor sites, treatment of residual disease following chemotherapy, or serious local problems. The disease can be controlled in 25% to 40% of patients with stage IIIE or IVE disease. As with stage IIE disease, the optimal chemotherapy regimen depends on the histologic subtype of NHL.