Objective: This study analyzes the effect of interventions aimed at reinducing remissions in patients with relapse or progression of malignant disease following allogeneic hematopoietic cell transplantation (HCT) using nonmyeloablative conditioning.
Methods: We performed a retrospective analysis of 81 instances of relapse or progression occurring among 224 patients given HCT as treatment of their hematologic malignancies. All patients received conditioning with 2 Gy total-body irradiation with or without fludarabine and with postgrafting immunosuppression with mycophenolate mofetil and cyclosporine.
Results: Overall survival of patients after relapse or progression was 36%. Fifteen of the 81 patients were given no interventions. Three of these 15 (20%) patients are alive with disease while 12 died with disease progression. Sixty-six patients (81%) received interventions, including withdrawal of immunosuppression (n=32), donor lymphocyte infusions (n=13), or chemotherapy (n=21). Twenty of the 66 (30%) are alive, 5 in complete remission, 4 in partial remission, 1 with stable and 10 with progressive disease. The overall response rate to intervention was 27%. Forty-six (70%) of the patients given interventions died, mainly due to relapse/progression. Patients not receiving interventions had a 1-year survival estimate of 15% compared to 41% in patients given interventions. Factors associated with survival in patients given intervention were disease response (p=0.002), disease category (p=0.001), and time to relapse from transplantation (p=0.0005).
Conclusions: While the overall prognosis of patients relapsing or progressing after nonmyeloablative HCT is poor, interventions such as the combined use of immunotherapy and chemotherapy can improve patient survival.