Successful combined treatment for primary central nervous system lymphoma with massive hemorrhage: Illustrative case.

Background: Primary central nervous system lymphoma (PCNSL) is a rare tumor, accounting for only 1-2% of all primary brain tumors, with most cases being diffuse large B-cell lymphoma (DLBCL). Because these lymphomas can rapidly worsen, prompt and accurate histological diagnosis, followed by early treatment initiation, are essential for improved prognosis. Extensive surgical resection has not demonstrated a clear survival benefit, and a minimally invasive biopsy is recommended. Hemorrhage within lesions is exceedingly rare, with few reports available. Case Description: A 73-year-old woman presented with progressive aphasia and right-sided hemiparesis. Imaging revealed a lesion from the left basal ganglia to the frontal lobe, suggestive of glioblastoma but not ruling out PCNSL. She developed deep vein thrombosis and pulmonary embolism, requiring anticoagulation therapy. Steroid therapy for acute brain edema provided transient improvement, but a massive intratumoral hemorrhage occurred. We performed a frameless robot-guided stereotactic biopsy and craniotomy for hematoma evacuation in a single operation. Final pathology confirmed DLBCL. Subsequent high-dose methotrexate plus rituximab therapy and radiation led to marked tumor shrinkage. Conclusion: Combining robot-guided stereotactic biopsy with craniotomy in PCNSL with hemorrhage ensures precise diagnosis, effective decompression, and optimal treatment planning.