Secondary cns lymphoma (BSH 2022)
Intro
Rare event —> limited evidence base —> individualised approach often required. For that reason I have only included broad overview notes here, the BSH good practice paper has lots of detail if needed.
Secondary CNS lymphoma includes three groups:
CNS + Systemic disease at first presentation, i.e. treatment naive (TN-SCNSL)
Isolated CNS relapse after previous treatment for systemic disease (RI-SCNSL)
CNS + Systemic relapse after previous treatment for systemic disease (RC-SCNSL)
Relevant because outcomes vary for the different clinical groups
investigations/work-up
Fitness assessment - e.g. Charlson Comorbidity Index (CCI), G8 screening tool, Cumulative Illness Rating Scale
Biopsy where possible
MRI brain +/- whole spine
CSF examination
PET-CT to assess systemic disease
Testicular ultrasound
Slit-lamp examination for intra-occular involvement
intensive Treatment
Evidence base is largely single arm phase 2 trials
Fit patients, <70 yo: best outcomes are with intensive induction followed by autograft
TRM is high —> Consider pre-phase steroids + adjusting first cycle to patient’s performance status
BSH guideline contains helpful algorithms summarising treatment options
MARIETTA (IELSG42) 2021 is preferred UK intensive treatment protocol
3x MATRix —> 3x R-ICE —> Autograft.
All patients 2yr OS = 46%
2yr PFS = 71% TN-SCNSL, 14% RC-SCNSL, 40% RI-SCNSL
TN-SCNSL
Intensive treatment may gain outcomes similar to DLBCL without CNS involvement
RI-SCNSL
Better outcomes than RC-SCNSL, and can be similar to TN-SCNSL
Intensive treatment may gain 2yr PFS of 60-70% (although not see in MARIETTA)
RC-SCNSL
Poor outcomes with intensive treatments, most patients do not make it to autograft
Consider a palliative approach
other treatments
Palliative Care
Best supportive care / Steroids / low dose radiotherapy
Whole brain radiotherapy (WBRT)
36Gy in 20# may achieve durable remission but very high rates of neurotoxicity / early dementia
CAR-T
Small no. of CNS patients in CAR-T studies, e.g. TRANSCEND 2020, show some response
Others
e.g. Lenalidomide & BTK inhibitors cross blood brain barrier but unlincensed.