An Update on Neurosurgical Management of Primary CNS Lymphoma in Immunocompetent Patients

Abstract

Primary central nervous system lymphomas (PCNSL) are rare CNS tumors that harbor a conspicuously longer diagnostic delay compared to other malignant brain tumors. The gold standard for diagnosis is stereotactic biopsy to acquire tissue for histopathological analysis and therefore neurosurgery plays a central role when reducing the diagnostic period is mandated. However, histopathological diagnosis could be complicated if the patient was preoperatively exposed to corticosteroids. Besides the histopathological result, diagnosis of a PCNSL also requires full diagnostic workup to exclude cerebral metastatic disease of a systemic lymphoma. Most reviews of PCNSL discuss recent advancements in systemic treatment options from an (neuro-)oncologic viewpoint, whereas our intention was to discuss the optimization of the diagnostic period and therefore describe current standards of imaging, summarizing the diagnostic workup, discussing the surgical workup and future diagnostic prospects as well as the influence of preoperative corticosteroid therapy to reduce the diagnostic delay of PCNSL patients.

Clinical Reasoning: A 67-Year-Old Man With Multiple Intracranial Lesions

“…However, steroids should be ideally deferred until a brain biopsy can be repeated, as steroids may decrease sample yield given the possibility of lymphoma or demyelinating disease. 4 The patient received a short course of dexamethasone. Antibiotics were not administered because of high concern for malignancy.…”

From the ER to the OR: Initial Evaluation of Primary Central Nervous System Lymphoma

“…At present, however, it should be noted that although liquid biopsy with cytogenetic/molecular pathology studies have the potential to replace stereotactic biopsy for the diagnosis of PCNSL, particularly when radiology demonstrates typical findings of PCNSL, there remains a lack of evidence to validate findings and stereotactic biopsy remains the current definitive modality for diagnosis. 98 At present, no biomarker demonstrates an adequate level of evidence to sufficiently replace stereotactic brain biopsy, and most ongoing investigations into potential candidate biomarkers maintain a need for prospective studies to validate biomarkers for use in routine clinical practice. 99…”

A Clinical Audit: Assessing the Diagnostic Delay of Primary Brain Tumors, Glioblastoma IDH-Wild Type and Primary CNS Lymphoma; Exploring the Use of CSF Liquid Biopsy

“…MRS can be used advantageously by classifying levels of metabolites in the brain to differentiate between PCNSL and Glioblastoma; an example of apparent diffusion coefficient (ADC) which is comparatively lower in PCNSL than in Glioblastoma [22] . Other common metabolites include Choline, Creatinine, Lactate, and lipids [23] . Yet, despite the support some imaging findings have in distinguishing or diagnosing, it is not established or relied upon due to the insignificant findings and figures that are showcased by different studies [24] .…”

“…There is a consensus that PCNSL patients deal with a longer delay than other types of tumors, and Glioblastoma in particular [23] . This hypothesis will be tested across different timespans to see if there is a noted difference in our sample, and at what stage the difference is bigger.…”