Characterizing second line and beyond therapies for primary central nervous system lymphomas

Area of Science:

• Neuro-oncology
• Hematology
• Clinical Pharmacy

Background:

• Primary central nervous system lymphoma (PCNSL) is a rare, aggressive brain cancer.
• High-dose methotrexate (HDMTX)-based regimens are standard frontline treatment.
• Relapse occurs in up to half of PCNSL patients, with no established preferred treatments for relapsed/refractory (R/R) disease.

Purpose of the Study:

• To characterize real-world therapies used for relapsed or refractory (R/R) PCNSL.
• To describe consolidation strategies following frontline treatment for PCNSL.

Main Methods:

• Retrospective, descriptive analysis of 54 adult PCNSL patients treated with HDMTX frontline.
• Data collected on frontline consolidation, and subsequent lines of therapy for R/R disease.
• Exclusion criteria included secondary CNS lymphoma, non-B cell PCNSL, and intraocular lymphoma.

Main Results:

• Thirty-one patients (57%) received consolidation (R-HDAC, WBRT, or both); 13 (24%) underwent autoSCT.
• Twenty-five patients progressed, with 17 receiving second-line treatment including WBRT, clinical trials, R2, HDMTX re-induction, ibrutinib, or R-HDAC.
• Subsequent lines of therapy showed significant regimen variability based on patient and physician factors.

Conclusions:

• Real-world treatment for R/R PCNSL is highly variable and individualized.
• Consolidation strategies post-frontline therapy also showed diversity.
• Prospective clinical trials are essential to define optimal therapeutic approaches for R/R PCNSL.