Autologous Stem Cell Transplantation with Thiotepa, Busulfan, and Cyclophosphamide (TBC) Conditioning in Patients with CNS Involvement by Non-Hodgkin Lymphoma

Primary central nervous system non-Hodgkin lymphoma (PCNSL) carries a poor prognosis and, although it responds to chemotherapy, fewer than 20% of patients are long-term disease-free survivors. Secondary CNS non-Hodgkin lymphoma (SCNSL) has an even worse prognosis with a median survival of only months and very few reported long-term survivors. For both of these groups of patients, there has been interest in using high-dose chemotherapy with autologous stem cell transplantation (ASCT) following conditioning with thiotepa, busulfan, and cyclophosphamide (TBC). We performed a retrospective review (from 2006-2010) of 32 patients from the Dana-Farber Cancer Institute and Massachusetts General Hospital with PCNSL or SCNSL who underwent ASCT with TBC conditioning. Of the 32 patients, 56% received TBC/ASCT after achieving brain magnetic resonance imaging (MRI) and/or cerebrospinal fluid complete response in brain, and 44% of patients were treated with TBC/ASCT in the setting of measurable CNS disease. The 100-day transplant-related mortality rate was only 3%. The most common nonhematologic grade 3 or 4 toxicity was mucositis, which occurred in 73% of patients. Notably, there was only 1 patient with prolonged significant neurologic toxicity that manifested as ataxia and dysphagia. The 1-year OS estimate is 93% (95% confidence interval [CI]: 75%-98%), and the 1-year progression-free survival (PFS) estimate is 90% (95% CI: 72%-96%) from the date of transplantation. Although these outcomes are encouraging, longer follow-up is required and comparison with other traditional ASCT regimens used for patients with non-Hodgkin lymphoma (NHL) is warranted.