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ABSTRACT: A 72-year-old man was admitted with left homonymous hemianopsia and hemiparesis. Magnetic resonance imaging revealed a heterogeneously enhanced lesion in the right parietal lobe. A brain biopsy showed acute demyelination without malignancy, which led to a diagnosis of tumefactive multiple sclerosis (MS). The patient received corticosteroid therapy and experienced clinical and radiological improvement. Six months later, new lesions appeared, and a second biopsy revealed proliferation of dysplastic lymphocytes. This led to a revised diagnosis of primary central nervous system lymphoma (PCNSL). Because PCNSL mimics MS both clinically and radiologically, PCNSL is difficult to diagnose. Performing repeated brain biopsies may therefore be required when PCNSL is strongly suspected.
Internal Medicine 01/2013; 52(4):483-8. · 0.94 Impact Factor
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ABSTRACT: Favorable responses to temozolomide chemotherapy have recently been reported in primary central nervous system lymphoma (PCNSL) patients who are refractory to high-dose methotrexate therapy. The gene encoding the DNA repair enzyme O (6)-methylguanine-DNA methyltransferase (MGMT) is transcriptionally silenced by promoter methylation in several human tumors, including gliomas and systemic lymphomas. MGMT promoter methylation is also a prognostic marker in glioblastoma patients treated with temozolomide. To validate temozolomide treatment in PCNSL, we applied methylation-sensitive high resolution melting (MS-HRM) analysis to quantitate MGMT methylation in PCNSL. MGMT promoter methylation was detected in tumors from 23 (51%) of 45 PCNSL patients, 11 of which were considered to have high (more than 70.0%) methylation status. Of the five recurrent PCNSLs treated with temozolomide, four cases responded, with three achieving complete response and one, a partial response. All four responsive PCNSLs had methylated MGMT promoters, whereas the non-responsive recurrent PCNSL did not. Thus, the use of quantitative MS-HRM analysis for the detection of MGMT promoter methylation has been suggested in PCNSL for the first time. The assay allows rapid and high-throughput evaluation of the MGMT methylation status, and seems to be promising in clinical settings. MGMT promoter methylation may become a useful marker for predicting the response of PCNSLs to temozolomide.
Journal of Neuro-Oncology 03/2012; 107(1):147-53. · 3.21 Impact Factor
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ABSTRACT: We report a case of pineal parenchymal tumor (PPT) in an 11-year-old girl. Brain magnetic resonance imaging (MRI) revealed a large tumor (48 mm) located in the pineal region with heterogeneous enhancement after gadolinium administration. The patient underwent tumor removal with craniotomy; only partial tumor resection could be performed because of massive intratumoral bleeding. Histopathological examination of the tumor showed lobular proliferation of round cells with moderate atypia. Cellularity varied by area, and focal Homer Wright rosettes were identified. Examination of tumor cells revealed a few mitoses (two mitotic figures per 10 high-powered fields), and immunohistochemical staining revealed positivity for synaptophysin, slight positivity for neurofilament protein (NFP) with antibody clone 2F11, and strong positivity for NFP with clone NF-M+H. The pathological diagnosis was pineal parenchymal tumor of intermediate differentiation grade II according to World Health Organization criteria despite a high (22%) MIB-1 labeling index (LI). The patient had a favorable clinical course after an intensified chemotherapy regimen designed for pineoblastoma and radiotherapy administered to the entire neuraxis, followed by stereotactic radiotherapy. In conclusion, MIB-1 LI could be a useful tool for deciding therapeutic strategies for PPT treatment when there is a discrepancy between clinical findings and pathological grading.
Brain Tumor Pathology 02/2012; · 1.19 Impact Factor
