Age-adjusted high-dose chemotherapy and autologous stem cell transplant in elderly and fit primary CNS lymphoma patients

BACKGROUND: Primary central nervous system lymphoma (PCNSL) is a diffuse large B-cell lymphoma (DLBCL) confined to the central nervous system (CNS) with rising incidence among patients > 65 years. Although elderly patients are able to tolerate aggressive systemic chemotherapy, previous studies have demonstrated inferior outcomes for patients who present with a poor performance status (PS) and older age. Usually, intensive treatment approaches including high-dose chemotherapy followed by autologous stem cell transplantation (HDT-ASCT) are only offered to patients younger than 65–70 years of age. METHODS: This is an open-label, multicentric, non-randomized, single arm phase II trial. We will recruit 51 immuno-competent patients with newly diagnosed PCNSL from 12 German centers. The objective is to investigate the efficacy of age-adapted induction treatment followed by HDT-ASCT. All enrolled patients will undergo induction chemotherapy consisting of 2 cycles of rituximab 375 mg/m(2)/d (days 0 & 4), methotrexate 3.5 g/m(2) (d1), and cytarabine 2 × 2 g/m(2)/d (d2–3) every 21 days. After 2 cycles of induction chemotherapy, patients achieving at least stable disease will undergo HDT-ASCT with busulfan 3.2 mg/kg/d (days − 7-(− 6)) and thiotepa 5 mg/kg/d (days − 5-(− 4)) followed by autologous stem cell transplantation. The primary endpoint of this study is 1-year progression-free survival (PFS). Secondary endpoints include PFS, overall survival, treatment response and treatment-related morbidities. Minimal follow-up after treatment completion is 12 months. DISCUSSION: Current treatment options for PCNSL have improved over the last years, resulting in the potential to achieve durable remission or cure in patients < 70 years. Age alone may not be the only criterion to select patients for this effective treatment approach and probably many elderly patients are undertreated just because of advanced age. There have been no multicentre trials investigating this curative treatment concept in elderly and fit PCNSL patients so far. We aim to answer whether HDT-ASCT is feasible and effective in fit patients > 65 years with newly-diagnosed PCNSL. TRIAL REGISTRATION: German clinical trials registry DRKS00011932 registered 18 August 2017. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12885-019-5473-z) contains supplementary material, which is available to authorized users.