ABSTRACT
The current standard of diagnosing central nervous system (CNS) lymphoma is stereotactic biopsy, however the procedure has a risk of surgical complication. Liquid biopsy of the CSF is a less invasive, non-surgical method that can be used for diagnosing CNS lymphoma. In this study, we established a clinically applicable protocol for determining mutations in MYD88 in the CSF of patients with CNS lymphoma. CSF was collected prior to the start of chemotherapy from 42 patients with CNS lymphoma and matched tumor specimens. Mutations in MYD88 in 33 tumor samples were identified using pyrosequencing. Using 10 ng each of cellular DNA and cell-free DNA (cfDNA) extracted from the CSF, the MYD88 L265P mutation was detected using digital PCR. The conditions to judge mutation were rigorously determined. The median Target/Total value of cases with MYD88 mutations in the tumors was 5.1% in cellular DNA and 22.0% in cfDNA. The criteria to judge mutation were then determined, with a Target/Total value of 0.25% as the cutoff. When MYD88 mutations were determined based on these criteria, the sensitivity and specificity were 92.2% and 100%, respectively, with cellular DNA; and the sensitivity and specificity were 100% with cfDNA. Therefore, the DNA yield, mutated allele fraction, and accuracy were significantly higher in cfDNA compared with that in cellular DNA. Taken together, this study highlights the importance of detecting the MYD88 L265P mutation in cfDNA of the CSF for diagnosing CNS lymphoma using digital PCR, a highly accurate and clinically applicable method.
Subject(s)
Central Nervous System Neoplasms/genetics , Liquid Biopsy/methods , Lymphoma/genetics , Mutation , Myeloid Differentiation Factor 88/genetics , Adult , Aged , Aged, 80 and over , Cell-Free Nucleic Acids/cerebrospinal fluid , Cell-Free Nucleic Acids/genetics , Cell-Free Nucleic Acids/isolation & purification , Central Nervous System Neoplasms/cerebrospinal fluid , Central Nervous System Neoplasms/diagnosis , DNA, Neoplasm/cerebrospinal fluid , DNA, Neoplasm/genetics , DNA, Neoplasm/isolation & purification , Female , High-Throughput Nucleotide Sequencing/methods , Humans , Lymphoma/cerebrospinal fluid , Lymphoma/diagnosis , Male , Middle Aged , Myeloid Differentiation Factor 88/cerebrospinal fluid , Polymerase Chain Reaction/methods , Sensitivity and SpecificityABSTRACT
Reliable biomarkers are needed to avoid diagnostic delay and its devastating effects in patients with primary central nervous system (CNS) lymphoma (PCNSL). We analysed the discriminating sensitivity and specificity of myeloid differentiation primary response (88) (MYD88) L265P mutation (mut-MYD88) and interleukin-10 (IL-10) in cerebrospinal fluid (CSF) of both patients with newly diagnosed (n = 36) and relapsed (n = 27) PCNSL and 162 controls (118 CNS disorders and 44 extra-CNS lymphomas). The concordance of MYD88 mutational status between tumour tissue and CSF sample and the source of ILs in PCNSL tissues were also investigated. Mut-MYD88 was assessed by TaqMan-based polymerase chain reaction. IL-6 and IL-10 messenger RNA (mRNA) was assessed on PCNSL biopsies using RNAscope technology. IL levels in CSF were assessed by enzyme-linked immunosorbent assay. Mut-MYD88 was detected in 15/17 (88%) PCNSL biopsies, with an 82% concordance in paired tissue-CSF samples. IL-10 mRNA was detected in lymphomatous B cells in most PCNSL; expression of IL-6 transcripts was negligible. In CSF samples, mut-MYD88 and high IL-10 levels were detected, respectively, in 72% and 88% of patients with newly diagnosed PCNSL and in 1% of controls; conversely, IL-6 showed a low discriminating sensitivity and specificity. Combined analysis of MYD88 and IL-10 exhibits a sensitivity and specificity to distinguish PCNSL of 94% and 98% respectively. Similar figures were recorded in patients with relapsed PCNSL. In conclusion, high detection rates of mut-MYD88 and IL-10 in CSF reflect, respectively, the MYD88 mutational status and synthesis of this IL in PCNSL tissue. These biomarkers exhibit a very high sensitivity and specificity in detecting PCNSL both at initial diagnosis and relapse. Implications of these findings in patients with lesions unsuitable for biopsy deserve to be investigated.
Subject(s)
Biomarkers, Tumor , Central Nervous System Neoplasms , Interleukin-10/cerebrospinal fluid , Lymphoma , Mutation, Missense , Myeloid Differentiation Factor 88/genetics , Neoplasm Proteins , Adult , Aged , Amino Acid Substitution , Biomarkers, Tumor/cerebrospinal fluid , Biomarkers, Tumor/genetics , Biopsy , Central Nervous System Neoplasms/cerebrospinal fluid , Central Nervous System Neoplasms/genetics , Central Nervous System Neoplasms/pathology , Female , Humans , Interleukin-10/genetics , Lymphoma/cerebrospinal fluid , Lymphoma/genetics , Male , Middle Aged , Myeloid Differentiation Factor 88/cerebrospinal fluid , Neoplasm Proteins/cerebrospinal fluid , Neoplasm Proteins/geneticsABSTRACT
Bing-Neel syndrome (BNS) is an uncommon presentation of Waldenström macroglobulinaemia (WM), seen during the course of the disease in about 1% of patients. BNS occurs when WM cells gain access to the central nervous system (CNS) causing neurological deficits. The diagnosis of BNS is suggested by the presence of radiological abnormalities, such as leptomeningeal enhancement on magnetic resonance imaging and confirmed by the presence of clonal lymphoplasmacytic cells and MYD88 L265P in the cerebrospinal fluid. The treatment of BNS requires agents with good penetration into the CNS, such as fludarabine, methotrexate and cytarabine. The novel Bruton Tyrosine Kinase inhibitor ibrutinib has shown CNS-penetrating properties, and recent data suggest a therapeutic role in BNS. In this review, we will discuss the clinical and pathological features, diagnostic criteria, treatment options and outcomes of patients with BNS.
