LETTER TO THE EDITOR
Comment on "Thoracic Intradural Extramedullary Cavernous Malformation Mimicking Meningioma"
2026 年 13 巻 p. 415-416
詳細
2026 年 13 巻 p. 415-416
We read with great interest the article by Takanori Fukunaga et al.,1) which introduced a case of thoracic intradural extramedullary lesion (Takanori Fukunaga, Shingo Toyota, Tomoaki Murakami, Shuki Okuhara, Teruaki Nagano, Kosei Okochi, Koichi Nakashima, Motoki Nakamura, Shuhei Yamada, Takamune Achiha, Maki Kobayashi, Haruhiko Kishima: Thoracic Intradural Extramedullary Cavernous Malformation Mimicking Meningioma. NMC Case Rep J. 2025 Apr 1;12:109–114). Although we commend the authors for their clinical insights, we wish to highlight the omission of capillary hemangioma (CH) from the differential diagnosis.
Notably, Yamamoto et al.2) recently reported a case of thoracic intra- and extramedullary CH in this journal. To date, nearly 100 cases of neuraxial CH have been documented. As previously reported in Japan, CH and Cavernous malformation (CM) are distinct clinicopathological entities.3)
Magnetic resonance imaging (MRI) characteristics of CH typically include iso-intensity on T1-weighted imaging, hyper-intensity on T2-weighted imaging, and strong homogeneous contrast enhancement, which may overlap with imaging features of other intradural extramedullary tumors.4-6) The MRI findings in the present case are consistent with the typical features of CH previously described. In contrast, the marginal hypo-intensity and heterogeneous internal signal intensity on T2-weighted imaging, which are characteristic of CM, were not observed.
Pathologically, the differentiation between CH and other vascular lesions, particularly CM and hemangioblastoma, remains a diagnostic challenge.7) Although CH is characterized by a lobular architecture of capillary vessels, CM typically presents with dilated hyaline vessels accompanied by thrombosis and hemosiderin deposition. Distinguishing among these features is critical because they define the histological identity of the lesion. Pathological findings of the present case revealed a proliferation of capillary vessels of varying sizes, resembling the architecture of CH. Notably, there was no evident hemosiderin deposition, which is typically characteristic of CM.
We observed that the neuroradiological and pathological findings in the present report bear a striking resemblance to the case described by Yamamoto et al.2) Given the poorly understood natural history of CH, we believe that a careful differential diagnosis between CH and CM might be beneficial for clinical management. Although the natural history of CH remains poorly defined, its bleeding risk may be lower than that of CM because no cases of hemorrhagic onset have been reported for spinal CH. Consequently, the necessity and timing of intervention may differ between the 2 entities. Furthermore, unlike CM, which is frequently associated with developmental venous anomalies, there have been no reports of spinal CH coexisting with other vascular lesions. These distinctions in bleeding potential and associated pathologies underscore the critical importance of a definitive diagnosis. Clarifying this diagnostic process would significantly strengthen the validity of the report and provide valuable data for future systematic reviews of these rare spinal pathologies.
All authors have no conflict of interest.
