Background
Central nervous system (CNS) prophylactic options for diffuse large B-cell lymphoma (DLBCL) are administered differently in most centers. Unfortunately, there is still not a consensus on which patients, which regimen, for how many cycles, and when prophylaxis should be administered. Thus, this remains an unmet clinical need.
Methods
We administered a survey study under the Lymphoma Scientific Subcommittee of the Turkish Society of Haematology. The questions were directed to hematologists through the monkey survey system.
Results
The CNS International Prognostic Index score is a factor that clinicians frequently use when deciding on prophylaxis and is considered reliable. Although the perspective on anatomical risk factors is similar to that reported in the literature, breast involvement is still considered a critical risk factor in Turkey. Participants considered double or triple hit and double/triple expressor lymphoma as significant risk factors. Various methods have been used to demonstrate CNS relapses. Intrathecal prophylaxis is the preferred method.
Conclusion
There are diverse methodological and technical ideas. The controversial results reported in the literature on the effectiveness of CNS prophylaxis may explain this finding. Although CNS prophylactic methods for patients with DLBCL are still controversial, the effect of secondary CNS involvement on survival is inevitable. Standard practices followed by national guidelines may be effective in reducing the variety of application methods and creating homogeneous results for efficacy and survival follow-up studies.

Keywords: Prophylaxis, Diffuse large B-cell lymphoma, High dosage methotrexate