For research, it was determined how often a brain biopsy for suspected CNS relapse of systemic hematological malignancies yielded new, actionable diagnostic information. Hematological malignancies were a range of genetic and histopathological illnesses that affected the blood. The propensity for brain involvement varies by entity, which can happen simultaneously or meta synchronously with the systemic lesion. Diffuse large B-cell lymphomas (DLBCLs) had a significant risk involving the brain. Patients in remission from systemic DLBCL may develop a lesion that suggests relapse in the brain. These patients were frequently subjected to brain biopsies. The authors hypothesized that brain biopsy would have lower diagnostic relevance in patients with a history of systemic DLBCL and a new brain MRI lesion than in individuals with non-DLBCL systemic DLBCL. The researchers looked back at patients who had brain biopsies between 2000 and 2019. Patients under 18 with a past systemic hematological malignancy in remission who presented with a new brain MRI lesion suggestive of CNS relapse met the inclusion criteria. Patients with CNS neoplasms, demyelinating diseases, or current systemic disease were excluded from the study. The immediate result was the proportion of individuals with a specific histological brain diagnosis relative to the systemic malignancy. The authors looked at overall survival, procedure-related morbidity, and 30-day mortality as a secondary measure.

About 60 individuals (40 men and 20 women) matched the criteria for inclusion; the median age at brain biopsy was 67 years (range 23–88 years). Between follow-ups, the median time was 8.5 months (range 0.1–231). Just 39 patients (65.0%) had DLBCL, while 21 (35%) had non-DLBCL malignancies. In comparison to 0 of 21 patients with non-DLBCL systemic malignancies, 35 of 36 (97.2%) patients with prior systemic DLBCL and a diagnostic biopsy revealed histological confirmation of the initial systemic malignancy (p<0.001). Morbidity and 30-day mortality were 8.3% and 10%, respectively; two of the six 30-day deaths were directly related to the biopsy. After a brain biopsy, the median overall survival was 10.8 months. Patients with a history of systemic DLBCL and suspected CNS relapse benefited from brain biopsy just a little, although they were at significant risk of morbidity and mortality. Brain biopsy remained crucial given the increased chance of discovering unique diagnostic entities in individuals with a history of non-DLBCL systemic cancers. Patients with a history of systemic DLBCL and a suspected brain relapse should likely get empirical therapy, avoiding therapeutic delays and the hazards of brain biopsy.