The Outcome of Diffuse Large B-Cell Lymphoma with CNS Involvement at Diagnosis, Single-Center Experience
Authors: Almansour Mubarak A , Saif Saif , Alhrbi Ziyad , Alhwaity Abdulrhamn , Almasrahi Ahmed , Alnejadi Waleed , anwar Khan Mohammed , Hussain Sarah surur , Absi Ahmad 
Published: November 2020

Introduction
Central nervous system involvement is uncommon in diffuse large B cell lymphoma but always associated with a poor prognosis. We reviewed the risk of CNS involvement at diagnosis, clinical features, and survival outcome of patients with diffuse large B cell lymphoma with CNS involvement.
Patients and Methods
All patients with diffuse large B cell lymphoma from January 2005 to December 2019 at Princess Noorah Oncology Center were retrospectively reviewed. We included patients 15 years old or over, with biopsy-proven diffuse large B cell lymphoma. Patients with HIV disease, double or triple hit lymphomas, or Burkitt's like lymphomas were excluded. CNS involvement was confirmed by clinical, brain imaging, cerebrospinal fluid flow cytometry or biopsy
Results
A total of 406 patients with DLBCL were identified. The median age was 58 years. The majority of patients had stage III and IV disease (68%) and had more than one site of extranodal involvement (66%). The majority of the patients had intermediate to high IPI (66%) and elevated LDH (67%). A large proportion of patients had high CNS IPI (36%), and a minority of patients received either intravenous prophylaxis high dose methotrexate (11%) or Intrathecal methotrexate (3%). The majority of patients were treated with R-CHOP chemotherapy (92%).
In total, 17 (4%) patients had CNS involvement: 9 patients (2.2 %) at diagnosis and 8 (2%) at relapse. All the nine patients who had CNS involvement at diagnosis had advanced-stage disease except one patient. Six patients had another extranodal involvement. Four out of nine patients had a non-germinal center phenotype, and all four patients had parenchymal rather than leptomeningeal involvement. All the patients received R-CHOP chemotherapy alternating with high dose methotrexate except one patient who received palliative treatment. Five out of nine patients achieved CR and survived.
For those patients who had CNS relapse, the median time to relapse was 11.8 months (range 6 to 19 months), and most of the patients experienced a relapse in the first 6-13 months. All patients had an advanced stage, extranodal involvement, intermediate to high CNS-IPI, and only two of them received high dose methotrexate, and one patient received radiotherapy. Only two patients are alive: one patient received high dose methotrexate and high dose Ara C followed by high dose chemotherapy and autologous stem cell transplant. Another patient received salvage R-ESHAP for systemic relapse alternating with intrathecal MTX and waiting for stem cell transplant. The 5-year overall and progression-free survival rates for the entire DLBCL group were 84% and 73 %, respectively.
Conclusion
CNS involvement in diffuse large B cell lymphoma carries a poor prognosis. Aggressive CNS-directed therapy should be considered, especially in young fit patients.

Disclosures
No relevant conflicts of interest to declare.