Long term follow up after autologous hematopoietic stem cell transplantation for low grade non-Hodgkin's lymphoma

Abstract

6660 Background: Autologous hematopoietic stem cell transplantation (AHSCT) in low-grade non-Hodgkin's lymphoma (NHL) can result in prolonged remission but most patients eventually relapse and die of their disease. We report long term outcomes of AHSCT for patients with relapsed low-grade NHL. Methods: Between May 1983 and 2001, 67 patients with low-grade NHL received an AHSCT at the University of Minnesota at a median of 28 months (5 to 182) from the time of diagnosis. At transplant, 62 patients (93%) were in complete remission (CR) or partial remission (PR), 5 (8%) had refractory disease and 9 (14%) had transformed into a higher grade NHL. Results: Post AHSCT, 32 patients (53%) were in CR and 19 (32%) were in PR. At a median follow-up of 8 years (2 to 18 years), overall survival (OS) was 50% (95% confidence interval (CI) 38–62%) at 4 years and 33% (95% CI 20–46%) at 10 and 18 years, whereas progression free survival (PFS) was 30% (95% CI 17–39%) at 4, 18% (95% CI 8–28%) at 10 and 14% (95% CI 4–25%) at 18 years. Transplant related mortality in the first 100 days (TRM) was 3% (95% CI 0–7%). Rate of relapse was 62% (95% CI 48–75%) at 4 and 72% (95% CI 56–87%) at 10 years. 11 patients (18%) developed myelodysplastic syndrome (MDS) / acute myeloid leukemia (AML) at 1 to 8 years post AHSCT and 3 developed solid tumors. In a multiple regression analysis, the International Prognostic Index (IPI) score at transplant was the most important predictor for both OS and PFS. The median OS has not been reached in patients with an IPI score of 0 at transplant, whereas it was 3.8, 2.3 and 1.6 years for IPI scores of 1, 2 and 3 respectively (P=0.002). Good response to AHSCT (CR/PR) (RR 0.4, 95% CI 0.2–0.9, P=0.04) and age less than 50 (RR 0.5, 95% CI 0.2–0.8, P=0.01) were also predictors of good OS and PFS. Conclusions: We present mature follow up data of patients undergoing AHSCT for relapsed low grade NHL and demonstrate extended OS and PFS. Long term remission is seen in nearly 20% of patients. However, prolonged survival is tempered by a significant risk of post transplant second malignancies including MDS/AML and solid tumors. Safer or earlier application of AHSCT may reduce these late risks and improve survival. No significant financial relationships to disclose.