RESUMEN

BACKGROUND AND OBJECTIVES: Despite general acceptance that corticosteroid therapy (CST) should be withheld before biopsy for suspected primary central nervous system lymphoma (PCNSL), there remains conflicting evidence surrounding the precise impact of preoperative CST on the histopathological diagnosis. The objective of this systematic review and meta-analysis was to describe and quantify the effects of preoperative CST on the diagnostic accuracy of biopsies for PCNSL. METHODS: Primary articles were screened from Ovid MEDLINE, Embase, Web of Science, and Scopus databases. Meta-analysis was performed for immunocompetent patients with histologically confirmed PCNSL. Subgroup and regression analyses were performed to assess the effects of biopsy type, CST duration, dose, and preoperative taper on the diagnostic accuracy. In addition, the sensitivity of cerebrospinal fluid (CSF) analyses for PCNSL was assessed. RESULTS: Nineteen studies, comprising 1226 patients (45% female; mean age: 60.3 years), were included. Preoperative CST increased the risk of nondiagnostic biopsy with a relative risk (RR) of 2.1 (95% CI: 1.1-4.1). In the stereotactic biopsy subgroup, the RR for nondiagnostic biopsy was 3.0 (95% CI: 1.2-7.5). CST taper, duration, and dose did not significantly influence diagnostic biopsy rates. The sensitivity of CSF cytology, including flow cytometry, for PCNSL was 8.0% (95% CI: 6.0%-10.7%). CONCLUSION: Our results suggest that preoperative CST reduces the diagnostic yield of stereotactic biopsies for PCNSL. We found no evidence that tapering CST before biopsy improves diagnostic rates. CSF analysis currently has a poor sensitivity for the diagnosis of PCNSL.

Asunto(s)

Corticoesteroides , Neoplasias del Sistema Nervioso Central , Linfoma , Técnicas Estereotáxicas , Humanos , Neoplasias del Sistema Nervioso Central/tratamiento farmacológico , Neoplasias del Sistema Nervioso Central/diagnóstico , Neoplasias del Sistema Nervioso Central/patología , Neoplasias del Sistema Nervioso Central/líquido cefalorraquídeo , Linfoma/tratamiento farmacológico , Linfoma/diagnóstico , Linfoma/patología , Biopsia , Corticoesteroides/uso terapéutico , Corticoesteroides/administración & dosificación , Cuidados Preoperatorios/métodos

RESUMEN

Background: The World Health Organization 2021 classification introduces molecular grading criteria for anaplastic meningiomas, including TERT promoter (TERTp) mutations and CDKN2A/B homozygous deletion. Additional adverse prognostic factors include H3K27me3 and BAP1 loss. The aim of this study was to explore whether these molecular alterations stratified clinical outcomes in a single-center cohort of grade 3 meningiomas. Additionally, we examined whether p16 and MTAP immunohistochemistry can predict CDKN2A/B status. Methods: Clinical and histopathological information was obtained from the electronic medical records of grade 3 meningiomas resected at a tertiary center between 2007 and 2020. Molecular testing for TERTp mutations and CDKN2A/B copy-number status, methylation profiling, and immunohistochemistry for H3K27me3, BAP1, p16, and methylthioadenosine phosphorylase (MTAP) were performed. Predictors of survival were identified by Cox regression. Results: Eight of 15 cases demonstrated elevated mitotic index (≥20 mitoses per 10 consecutive high-power fields), 1 tumor exhibited BAP1 loss, 4 harbored TERTp mutations, and 3 demonstrated CDKN2A/B homozygous deletion. Meningiomas with TERTp mutations and/or CDKN2A/B homozygous deletion showed significantly reduced survival compared to anaplastic meningiomas with elevated mitotic index alone. Immunohistochemical loss of p16 and MTAP demonstrated high sensitivity (67% and 100%, respectively) and specificity (100% and 100%, respectively) for predicting CDKN2A/B status. Conclusions: Molecular alterations of grade 3 meningiomas stratify clinical outcomes more so than histologic features alone. Immunohistochemical loss of p16 and MTAP show promise in predicting CDKN2A/B status.

RESUMEN

Diffuse gliomas are the most common type of primary central nervous system (CNS) neoplasm to affect the adult population. The diagnosis of adult diffuse gliomas is dependent upon the integration of morphological features of the tumour with its underlying molecular alterations, and the integrative diagnosis has become of increased importance in the fifth edition of the WHO classification of CNS neoplasms (WHO CNS5). The three major diagnostic entities of adult diffuse gliomas are as follows: (1) astrocytoma, IDH-mutant; (2) oligodendroglioma, IDH-mutant and 1p/19q-codeleted; and (3) glioblastoma, IDH-wildtype. The aim of this review is to summarize the pathophysiology, pathology, molecular characteristics, and major diagnostic updates encountered in WHO CNS5 of adult diffuse gliomas. Finally, the application of implementing the necessary molecular tests for diagnostic workup of these entities in the pathology laboratory setting is discussed.