Fukuda Yukiko, Takahashi Satoru, Nakamura Michiko, Endo Masashi, Ogawa Kazunari, Kawahara Masahiro, Akahane Keiko, Ito Shoko, Kanda Yoshinobu, Mori Harushi, Shirai Katsuyuki
Department of Radiology, Jichi Medical University Hospital, Tochigi, Japan.
Department of Radiology, Jichi Medical University Saitama Medical Center, Saitama, Japan.
Case Rep Oncol. 2022 Jul 1;15(2):674-681. doi: 10.1159/000524825. eCollection 2022 May-Aug.
Radiation myelopathy is a rare, late-stage adverse event that develops following irradiation at or above 50 Gy. Here, we report a case of irreversible paraplegia caused by palliative radiation (20 Gy in 5 fractions) to the spinal cord combined with intrathecal methotrexate (IT-MTX). A 69-year-old man presented with back pain, prompting a diagnosis of acute myeloid leukemia. At the first visit, he complained of muscle weakness and hypoesthesia in both legs; spinal magnetic resonance imaging (MRI) revealed an epidural mass compressing the spinal cord at the fifth to seventh level of the thoracic vertebrae. This was considered to be an extramedullary lesion of leukemia, and he received remission induction therapy including IT-MTX; palliative radiation (20 Gy in 5 fractions) of the epidural mass was initiated the following day. Then, during the course of consolidation therapy, a second IT-MTX was performed after 1 month and a third after 3 months. While the consolidation therapy was complete, yielding remission, he developed sudden paraplegia, as well as bladder and bowel dysfunction (BBD), 10 months later. Spinal MRI showed extensive intramedullary high signal intensity on T2-weighted image, including the irradiation field. It was thought myelopathy was due to irradiation of the spinal cord combined with IT-MTX. He immediately received steroid pulse therapy; however, the paraplegia and BBD did not improve. It is extremely rare for irreversible radiation myelopathy to occur with IT-MTX and palliative radiation to the spinal cord. We believe that even with low-dose palliative radiation, caution is required for combined use with IT-MTX.
放射性脊髓病是一种罕见的晚期不良事件，在接受50 Gy及以上剂量照射后发生。在此，我们报告一例因脊髓姑息性放疗（5次分割，共20 Gy）联合鞘内注射甲氨蝶呤（IT-MTX）导致的不可逆截瘫病例。一名69岁男性因背痛就诊，诊断为急性髓系白血病。初诊时，他主诉双腿肌肉无力和感觉减退；脊髓磁共振成像（MRI）显示胸5至胸7水平硬膜外肿块压迫脊髓。这被认为是白血病的髓外病变，他接受了包括IT-MTX在内的缓解诱导治疗；次日开始对硬膜外肿块进行姑息性放疗（5次分割，共20 Gy）。然后，在巩固治疗过程中，1个月后进行了第二次IT-MTX注射，3个月后进行了第三次注射。虽然巩固治疗完成并实现缓解，但10个月后他突然出现截瘫以及膀胱和肠道功能障碍（BBD）。脊髓MRI显示在T2加权图像上包括照射野在内的广泛髓内高信号强度。考虑脊髓病是由于脊髓放疗联合IT-MTX所致。他立即接受了类固醇冲击治疗；然而，截瘫和BBD并未改善。IT-MTX与脊髓姑息性放疗同时发生不可逆放射性脊髓病极为罕见。我们认为，即使是低剂量的姑息性放疗，与IT-MTX联合使用时也需要谨慎。
