Salvage central lymphatic irradiation in follicular lymphomas following failure of chemotherapy: a feasibility study

Abstract

Purpose: Management of follicular lymphoma after chemotherapy failure has been controversial and has ranged from watchful waiting to high-dose chemotherapy. High-dose chemotherapy with bone marrow reconstitution may produce clinical and molecular complete responses at the risk of serious morbidity and mortality. It has been previously reported that central lymphatic irradiation (CLI) can achieve long-term relapse-free survival in patients with Stage I, II, or III follicular lymphoma. Therefore, we investigated the feasibility of treating patients in whom front-line chemotherapy failed with salvage CLI instead of instituting more intensive chemotherapy. Methods and Materials: Salvage CLI with curative intent for patients with follicular lymphoma was started at The University of Texas M. D. Anderson Cancer Center in 1992. Eleven patients whose disease showed poor response to or relapsed after chemotherapy were managed with this approach. The median age of the patients was 61 years. Criteria for exclusion included bone marrow involvement or other evidence of Ann Arbor Stage IV disease at any time during the course of the disease. Overall survival and relapse-free survival were calculated from the first day of CLI. Results: Ten patients were alive at a median follow-up of 25 months (range 9–73 months). The treatment was well tolerated in general. Two patients could not complete CLI: one 75-year-old patient owing to prolonged platelet count depression and deterioration in general medical condition, and a 66-year-old patient because of exacerbation of preexisting pancytopenia and worsening of heart disease. Everyone who completed CLI remains in remission at the time of this report, except for one patient who had a relapse in the right lacrimal gland at 32 months. This patient was treated with local radiation therapy and is free of disease. Eventual recovery of the blood counts was observed for the patients who completed CLI. Conclusion: These results demonstrate for the first time that with CLI, it is possible to achieve complete remission of acceptable quality in follicular lymphoma patients who experience a chemotherapy failure. The main toxicity is limited to transient depression in hematological profiles. The treatment is fairly well tolerated and seems to carry little risk compared with high-dose chemotherapy and bone marrow rescue. Salvage CLI may not necessarily compromise future treatment with chemotherapy, including autologous bone marrow or stem cell transplantation, because the patients’ blood counts recover.