Primary Central Nervous System Tumors

Challenging Cases in Neuro-Oncology

“…The primary treatment paradigm revolves around a regimen of intravenously administered high-dose methotrexate (HD-MTX), a dihydrofolate reductase inhibitor which impairs folic acid metabolism in turn impairing DNA synthesis which is essential for rapidly dividing neoplasms such as DLBCL. 8 9 High doses of MTX are rapidly infused to facilitate a cytotoxic concentration of drug crossing the blood–brain barrier (BBB). This is typically performed in the inpatient setting and is accompanied by substantial amounts of bicarbonate IV fluids to alkalinize the urine, which allows for adequate renal excretion of drug preventing its crystallization within the renal tubules.…”

“…In turn, it reconstitutes the impairment of folic acid metabolism in the bone marrow without impacting the CNS activity of MTX. 9 Uncertainty remains regarding the optimal dose and duration of HD-MTX and if it should be paired with other agents and if so which ones. Greater uncertainty exists regarding the optimal consolidation regimen.…”

“…Biopsy was performed and pathology revealed a diffuse large B cell lymphoma (DLBCL). Staging 1 was performed and did not show evidence of extra-CNS disease. In turn, the diagnosis was consistent with a primary CNS lymphoma (PCNSL).…”

“…Early therapeutic studies of PCNSL did not demonstrate any survival benefit with extensive resection in this treatment-responsive disease. 8 9 There are some recent studies, however, which call into question this approach. 10…”

“…In addition, serum HIV testing should be performed, as HIV infection with associated low CD4 count is a risk factor for CNS lymphoma. 1 While PCNSL is typically a very aggressive disease, it is potentially curable, unlike many of the entities encountered in neuro-oncology. In turn, optimal efficient management by an experienced clinical team has value.…”