Diagnostic accuracy of cerebrospinal fluid liquid biopsy and MRI for leptomeningeal metastases in solid cancers: A systematic review and meta-analysis

Abstract

Background Cerebrospinal fluid (CSF) cytology remains the gold standard approach for diagnosing of leptomeningeal metastases (LM), but has clinical problems due to its low sensitivity. This systemic review and meta-analysis evaluated the diagnostic accuracy of the novel CSF biomarkers of liquid biopsy and magnetic resonance imaging (MRI) for detecting LM in patients with solid cancers. Methods A systematic search of electronic databases was conducted to identify all published diagnostic accuracy studies on CSF liquid biopsies and MRI since January 2000 with registration for PROSPERO (#CRD42022301988). Articles were selected based on pre-defined inclusion and exclusion criteria following the PRISMA 2020 statement. Results The search yielded 3790 citations, and 10 studies with 668 patients were included in the final analysis. The pooled prevalence of LM was 50.9% (340/668). The respective sensitivity and specificity for index tests were as follows: circulating tumor cells (CTC), 87.0% (95% confidence interval [CI] 77.9%-92.6%) and 93.8% (86.9%-97.2%); cell-free tumor DNA, 97.9% (19.3%-100%) and 89.0% (25.3%-99.5%); MRI 59.4% (60.7%-76.9%) and 97.6% (77.3%-99.8%); cytology, 71.9% (54.7%-82.9%) and 100%. The diagnostic odds ratio was 100.6 (29.38-344.09) for CTC and 93.3 (88.42-1034.05) for MRI. Conclusion Novel CSF liquid biopsies and MRI may offer improved diagnostic accuracy for LM from solid cancers; however, further research is required to specify the threshold values and to construct standards for individual primary cancers.

Numb cheek syndrome in breast cancer: a case report

“…Furthermore, triple-negative breast cancer, like that of our patient, has also been reported to have a preponderance for early nervous system metastases, with approximately one-third of cases eventually developing brain metastases ( 14 , 15 ). The lack of malignant cells in our patient’s CSF cytology does not rule out leptomeningeal metastasis or direct parenchymal infiltration, because CSF cytology has suboptimal sensitivity for both kinds of metastases ( 16 , 17 ). However, when combined with the normal CSF protein concentration and lack of CSF pleocytosis in our patient, leptomeningeal metastasis becomes less likely, given that the majority of patients with leptomeningeal metastasis will have abnormalities in both CSF cell counts and protein concentrations ( 18 ).…”

Nonbrain metastases seen on magnetic resonance imaging during metastatic brain tumor screening

“…At diagnosis, brain and extracranial metastases are seen in > 70% and > 80% of LMC patients, respectively [ 22 ]; hence, when the above signs are seen on head MRI and LMC is suspected, careful interpretation is required to identify both brain and nonbrain metastases [ 22 ].…”

A Hangover Under 177Lu-PSMA-617 Therapy

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“…Moreover, the diagnosis of leptomeningeal carcinomatosis remains difficult. A recent meta-analysis reported a specificity of 97.6% for MRI in this topic 9 . Above all, it revealed a lack of sensitivity, only 59.4%.…”