Matsubayashi Jun, Tsuchiya Kuniaki, Matsunaga Takashi, Mukai Kiyoshi
Department of Diagnostic Pathology, Tokyo Medical University, Nishi-Shinjuku Shinjuku-ku, Tokyo, Japan.
Neuropathology. 2009 Apr;29(2):105-15. doi: 10.1111/j.1440-1789.2008.00945.x. Epub 2008 Jul 8.
This report concerns two rare autopsy cases of methotrexate (MTX)-related leukoencephalopathy without radiation therapy. In the first case, there were widespread necrotic foci with prominent spheroids, that is, disseminated necrotizing leukoencephalopathy (DNL), mainly in the cerebral white matter. In contrast, in the second case, there were widespread demyelinated foci without significant axonal changes, which we would like to name disseminated demyelinating leukoencephalopathy (DDL), mainly in the cerebral white matter. We emphasize that the pathology of pure MTX-related leukoencephalopathy is not uniform, and may show at least two kinds of histologic change. Furthermore, both cases did not develop significant vascular changes, which are usually induced by radiation therapy. The distribution of the lesions in two cases was examined by large specimens, including hemisphere specimens. The distribution of the lesions in the brain of our cases was also different. In the first case, the DNL lesions were predominantly distributed in the frontal and temporal lobes. In the second case, the DDL lesions were prominently localized in the occipital lobe. To our knowledge, this is the first report describing not only the pathological findings of MTX-related leukoencephalopathy without irradiation but also the precise distributions of the lesions.
本报告涉及两例罕见的未接受放射治疗的甲氨蝶呤（MTX）相关性白质脑病尸检病例。第一例中，存在广泛的坏死灶，并伴有显著的球形体，即主要位于脑白质的播散性坏死性白质脑病（DNL）。相比之下，第二例中，存在广泛的脱髓鞘病灶，且无明显的轴突改变，我们将其命名为主要位于脑白质的播散性脱髓鞘性白质脑病（DDL）。我们强调，单纯MTX相关性白质脑病的病理表现并不一致，可能至少呈现两种组织学改变。此外，两例均未出现通常由放射治疗引起的显著血管改变。通过包括半球标本在内的大体标本检查了两例病例中病变的分布情况。我们病例脑部病变的分布也有所不同。第一例中，DNL病变主要分布在额叶和颞叶。第二例中，DDL病变主要局限于枕叶。据我们所知，这是首例不仅描述了未接受放疗的MTX相关性白质脑病的病理发现，还描述了病变精确分布的报告。
