Salvage abdominal irradiation for refractory non-Hodgkin's lymphoma.

Background: Abdominal irradiation, as a part of treatment, is often ignored in the management of refractory non-Hodgkin's lymphoma (NHL).

Objective: To evaluate the efficacy and the toxicity of this approach after failure of chemotherapy.

Materials And Methods: 27 patients with intraabdominal lymphoma underwent salvage irradiation between 1982 and 2001. All patients were treated with a Cobalt-60 machine. The total dose administered to the abdomen was 18-20 Gy at the rate of 1.5-1.8 Gy per daily fraction, followed by a boost to gross disease up to 20 Gy. All patients had previously been heavily pretreated with chemotherapy. Fourteen patients, nine with follicular and five with diffuse lymphomas, had primary refractory tumors that had never achieved remission. Thirteen patients, six with follicular and seven with aggressive tumors, had refractory relapsed tumors after achieving one or more complete remissions.

Results: The response rate was 77%. The median follow-up was 53 months. The 5-year and 10-year survival rates were 25 and 17%, respectively. The in-field and out-of-field recurrence rates were 22 and 33%, respectively. Survival rates were significantly better for patients with refractory relapse compared to those with primary refractory lymphoma (P < 0.01). There was no significant difference in terms of response, recurrence, or survival rates between follicular and aggressive types. Out-of-field recurrence occurred more frequently in initial stage III and IV disease. Toxic deaths occurred in three patients (11%).

Conclusion: Salvage radiotherapy for refractory abdominal NHL is a feasible alternative for both follicular and diffuse subtypes and may provide significant palliation and prolongation of survival. It is less effective in patients with primary refractory NHL than in those with refractory relapsed NHL.