RESUMEN
Delays and risks associated with neurosurgical biopsies preclude timely diagnosis and treatment of central nervous system (CNS) lymphoma and other CNS neoplasms. We prospectively integrated targeted rapid genotyping of cerebrospinal fluid (CSF) into the evaluation of 70 patients with CNS lesions of unknown etiology. Participants underwent genotyping of CSF-derived DNA using a qPCR-based approach for parallel detection of single-nucleotide variants in the MYD88, TERT promoter, IDH1, IDH2, BRAF and H3F3A genes within 80 minutes of sample acquisition. Canonical mutations were detected in 42% of patients with neoplasms, including cases of primary and secondary CNS lymphoma, glioblastoma, IDH-mutant brainstem glioma and H3K27M-mutant diffuse midline glioma. Genotyping results eliminated the need for surgical biopsies in 7/33 (21.2%) cases of newly diagnosed neoplasms, resulting in significantly accelerated initiation of disease-directed treatment (median 3 vs 12 days; p = 0.027). This assay was then implemented in a Clinical Laboratory Improvement Amendments (CLIA) environment, with 2-day median turnaround for diagnosis of central nervous system lymphoma from 66 patients across 4 clinical sites. Our study prospectively demonstrates that targeted rapid CSF genotyping influences oncologic management for suspected CNS tumors.
RESUMEN
OBJECTIVES: The folate antagonist high-dose methotrexate (HD-MTX) is integral to induction chemotherapy for primary CNS lymphoma (PCNSL); however, it can be associated with leukoencephalopathy. Methylenetetrahydrofolate reductase (MTHFR) is involved in intracellular folate depletion. We assessed whether MTHFR polymorphisms affect the risk of leukoencephalopathy. METHODS: We retrospectively searched our database at the Massachusetts General Hospital for newly diagnosed PCNSL treated with HD-MTX (without radiotherapy nor intrathecal chemotherapy). RESULTS: Among 68 patients with PCNSL, MTHFR polymorphisms were found in 60 individuals (88.2%) including a 677CâT genotype, a 1298AâC genotype, or a combined 677CâT/1298AâC genotype. Neither MTX clearance nor response to induction therapy was affected by specific genotypes, and complete response was achieved in 72.1% of patients by HD-MTX-based induction. However, the 1298AâC genotype was associated with increased frequency and severity of leukoencephalopathy over time (odds ratio 4.0, CI 1.5-11.4). Such genotype predicted treatment-induced leukoencephalopathy with a sensitivity of 71.0% and a specificity of 62.2% (area under the curve 0.67, CI 0.5-0.8; p = 0.019). While progression-free survival did not differ in genotype-based subgroups, overall survival was lower for the 1298AâC genotype. DISCUSSION: The MTHFR 1298AâC genotype may serve to identify patients with PCNSL at elevated risk of HD-MTX-induced leukoencephalopathy. This seems to translate into reduced survival, potentially due to decreased functional status.
Asunto(s)
Linfoma , Metotrexato , Humanos , Metotrexato/efectos adversos , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Estudios Retrospectivos , Ácido Fólico , Genotipo , Linfoma/tratamiento farmacológico , Linfoma/genéticaRESUMEN
Diagnosing primary central nervous system lymphoma (PCNSL) frequently requires neurosurgical biopsy due to nonspecific radiologic features and the low yield of cerebrospinal fluid (CSF) studies. We characterized the clinical evaluation of suspected PCNSL (N = 1007 patients) and designed a rapid multiplexed genotyping assay for MYD88, TERT promoter, IDH1/2, H3F3A, and BRAF mutations to facilitate the diagnosis of PCNSL from CSF and detect other neoplasms in the differential diagnosis. Among 159 patients with confirmed PCNSL, the median time to secure a diagnosis of PCNSL was 10 days, with a range of 0 to 617 days. Permanent histopathology confirmed PCNSL in 142 of 152 biopsies (93.4%), whereas CSF analyses were diagnostic in only 15/113 samplings (13.3%). Among 86 archived clinical specimens, our targeted genotyping assay accurately detected hematologic malignancies with 57.6% sensitivity and 100% specificity (95% confidence interval [CI]: 44.1% to 70.4% and 87.2% to 100%, respectively). MYD88 and TERT promoter mutations were prospectively identified in DNA extracts of CSF obtained from patients with PCNSL and glioblastoma, respectively, within 80 minutes. Across 132 specimens, hallmark mutations indicating the presence of malignancy were detected with 65.8% sensitivity and 100% specificity (95% CI: 56.2%-74.5% and 83.9%-100%, respectively). This targeted genotyping approach offers a rapid, scalable adjunct to reduce diagnostic and treatment delays in PCNSL.
Asunto(s)
Neoplasias del Sistema Nervioso Central , Técnicas de Genotipaje , Linfoma no Hodgkin , Mutación , Proteínas de Neoplasias , Reacción en Cadena en Tiempo Real de la Polimerasa , Adulto , Neoplasias del Sistema Nervioso Central/líquido cefalorraquídeo , Neoplasias del Sistema Nervioso Central/diagnóstico , Neoplasias del Sistema Nervioso Central/genética , Femenino , Humanos , Linfoma no Hodgkin/líquido cefalorraquídeo , Linfoma no Hodgkin/diagnóstico , Linfoma no Hodgkin/genética , Proteínas de Neoplasias/líquido cefalorraquídeo , Proteínas de Neoplasias/genéticaRESUMEN
LESSONS LEARNED: The findings from this study using monotherapy with pemetrexed in a pretreated patient population are, overall, encouraging. Unlike high-dose methotrexate, which requires several days of inpatient hospitalization, pemetrexed is relatively easy to administer in the outpatient setting and remains a viable treatment option in this patient population. The maximum tolerated dose of pemetrexed administered (900 mg/m2 every 2 weeks) was generally well tolerated and showed activity in patients with relapsed or refractory CNSL. BACKGROUND: There is currently no standard salvage treatment for patients with relapsed/refractory central nervous system (CNS) lymphoma (CNSL). We report the results of a phase I study of pemetrexed, an antifolate drug with broader activity than methotrexate (MTX). We provide the safety, tolerability, and maximum tolerated dose (MTD) of pemetrexed in patients with recurrent CNSL. METHODS: Through October 2015, 17 patients with relapsed/refractory CNSL received pemetrexed every 2 weeks with the first cohort receiving 600 mg/m2 and dose escalation in increments of 300 mg/m2 to a maximum of 1,200 mg/m2 . Three patients were to enroll at each dose level with expansion to six patients in the event of dose-limiting toxicity. Patients with both primary CNS lymphoma (PCNSL) and secondary CNS lymphoma (SCNSL) could be enrolled. RESULTS: Seventeen patients were evaluable with a median age of 63.7 years. Main adverse events included fatigue (82.4%), anemia (82.4%), and neutropenia (70.6%). The MTD was established at 900 mg/m2 . Dose-limiting toxicities were recorded in one patient in the 600 mg/m2 cohort and in two patients in the 1,200 mg/m2 cohort. Fourteen patients were evaluable for response assessment; 21.4% achieved a complete response, 35.7% had a partial response, 14.3% had stable disease, and 28.6% had progressive disease. The median progression-free survival was 4.2 months. The median overall survival was 44.5 months. In the original study protocol, the plan was to add an expansion cohort of six patients at MTD level. However, the first phase of the study was characterized by slow recruitment. Therefore, after achieving the primary objective of the study and establishing the MTD, the investigators decided to amend the protocol and to close the study. CONCLUSION: Pemetrexed administered at 900 mg/m2 every 2 weeks exhibits single-agent activity in patients with recurrent CNSL; it is well tolerated, and side effects are manageable.
Asunto(s)
Linfoma no Hodgkin , Linfoma , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Sistema Nervioso Central , Humanos , Linfoma/tratamiento farmacológico , Linfoma no Hodgkin/tratamiento farmacológico , Dosis Máxima Tolerada , Persona de Mediana Edad , Recurrencia Local de Neoplasia/tratamiento farmacológico , Pemetrexed/uso terapéuticoRESUMEN
BACKGROUND: High-dose thiotepa, busulfan, and cyclophosphamide (TBC) with autologous stem cell transplantation (ASCT) has been used in patients with central nervous system (CNS) involvement by non-Hodgkin lymphoma (NHL). Despite limited penetration into the CNS, rituximab is active in primary CNS NHL. Therefore, high-dose rituximab was combined with TBC for ASCT in patients with CNS NHL. METHODS: A single-arm phase 2 trial using high-dose rituximab with cytarabine for stem cell mobilization followed by high-dose rituximab combined with thiotepa, busulfan, and cyclophosphamide (R-TBC) for ASCT was conducted. Doses of rituximab at 1000 mg/m(2) were given on days 1 and 8 of mobilization and on days -9 and -2 of TBC. The primary endpoint was efficacy. RESULTS: Thirty patients were enrolled. Eighteen patients had primary CNS NHL (12 with complete remission (CR)/first partial remission (PR1) and 6 with CR/PR2), and 12 patients had secondary CNS lymphoma (5 with CR/PR1 and 7 with CR/PR2 or beyond). All patients were in partial or complete remission. Twenty-nine patients proceeded to R-TBC ASCT. Two patients developed significant neurotoxicity. The 100-day nonrelapse mortality rate was 0%, and 1 patient died because of nonrelapse causes 5 months after ASCT. For all patients, at a median follow-up of 24 months (range, 12-40 months), the estimated 2-year progression-free survival rate was 81% (95% confidence interval, 59%-92%), and the 2-year overall survival rate was 93% (95% confidence interval, 76%-98%). There were no relapses or deaths among the 18 patients with primary CNS lymphoma. CONCLUSIONS: For patients with CNS involvement by B-cell NHL and especially for patients with primary CNS NHL, R-TBC ASCT shows encouraging activity and merits further study.