Sarcomatoid malignant mesothelioma presenting with intramedullary spinal cord metastasis: a case report and literature review

Abstract

Study Design Case report. Objective Malignant mesothelioma (MM) is an uncommon tumor of the pleural epithelium with a predilection for local spread into adjacent tissues. The sarcomatoid type accounts for ∼10% of MM cases and is associated with poorer survival than the epithelioid, desmoplastic, and biphasic types. MM commonly presents with involvement of the vertebral body or epidural space. However, intradural spinal extension of MM is extremely rare. Only eight cases of intradural spinal extension have been reported. We report this rare case and discuss the clinical manifestations of intradural spinal extension of MM with literature review. Methods This report describes the case of a 62-year-old man with Brown-Séquard syndrome and radiculopathy of the left C5 nerve root detected during treatment for pleural sarcomatoid MM. Magnetic resonance imaging (MRI) showed an intramedullary lesion at the C3 level and a small nodule at the left C5 nerve root with cervical canal stenosis. Results The patient underwent surgery, and intramedullary metastasis of sarcomatoid MM was diagnosed. Subsequently, radiotherapy was administered, resulting in temporary improvement of the patient's condition. Thereafter, his condition gradually deteriorated, and follow-up MRI showed a more extensive residual C3 intramedullary lesion. Thus, a second surgery was performed after chemotherapy, but the patient died 5 months after the initial diagnosis. Conclusion We present this rare case, and emphasize intramedullary spinal cord metastasis of MM as differential diagnosis in primary cord lesion.

Keywords: Brown-Séquard syndrome; Radiculopathy; dissemination; laminoplasty; positron emission tomography; radiotherapy.

Fig. 1

Axial co-registered positron emission tomography (PET)-computed tomography (CT) images before thoracoscopic chest wall biopsy (A, B) and magnetic resonance imaging (MRI) scans obtained upon the patient's presentation of Brown-Séquard syndrome and left C5 radiculopathy (C, D, E, F, G). Sagittal (C) T2-weighted image (T2WI). Sagittal (D) and axial (E, F, G) contrast-enhanced T1-weighted image. PET-CT showed hypermetabolic fluorodeoxyglucose uptake (SUV_max 19.9) within the pleural mass and adjacent chest wall (arrows in A). MRI showed extended abnormal hyperintensity on T2WI (C) and a left C3 intramedullary lesion (arrows in D) and a small nodule at the left C5 nerve root (arrow in G). An ill-defined flame-shaped region of enhancement at the superior/inferior lesion margins (flame sign; arrows in E) and a more intense thin rim of peripheral enhancement around an enhancing lesion (rim sign; arrows in F) were observed.

Fig. 2

Intraoperative photograph (A) and pathologic findings from the specimen of the intramedullary spinal cord tumor (B, C, D). A poorly circumscribed grayish tumor was observed (A). Hematoxylin and eosin staining indicated sarcomatoid malignant mesothelioma consisting of spindle cells arranged in fascicles or with a haphazard distribution (C). These atypical cells were positive for CAM 5.2 (C) and AE1/AE3 (D). Scale bar: 200 μm.

Fig. 3

Follow-up magnetic resonance imaging (MRI) scans before (A) and after (B) the second surgery (sagittal contrast-enhanced T1-weighted image). MRI before the second surgery showed extension of the C3 intramedullary lesions (arrows in A). Gross removal of the lesion after the second surgery (B).