Figure 1
Eden classification
Dumbbell tumour of spine
SectionNeuroradiology
Case TypeClinical Cases
AuthorsSarma SK
Connected authors
43 years, female
Clinical History
A 43-year-old female patient presented with neck and back pain and gradual onset weakness of all limbs for the last 3-4 months.
Imaging Findings
The patient presented at our hospital's OPD with history of neck and back pain and weakness of limbs since last 3-4 months. Neurological examination revealed radicular pain on the right upper limb. Cervical X-ray revealed scoliosis with widening of neural foramina at C1-C2 level on the right side. MR study of the cervical spine revealed an approximately 70x36 mm sized solid lesion which has both intra and extraspinal components on the right side between C1 and C2 arches. The intraspinal component has significantly compressed the proximal cervical spinal cord and pushed it towards the left side. The lesion was isointense on T1 and hyperintense on T2 images and showed strong post contrast enhancements following gadolinium administration. There were few small non enhancing areas within the lesion. MR features were suggestive of neurogenic dumbbell tumour. Post-operative biopsy confirmed schwannoma.
Discussion
The dumbbell tumour is generally understood to demonstrate a dumbbell shape. However, the term “dumbbell tumours” does not refer simply to the dumbbell shape, but it is a conceptual term meaning tumours that connect two or more separate regions, such as intradural, epidural, and paravertebral spaces. Therefore, tumours with intradural and intraforaminal involvement, and with intraforaminal and paravertebral involvement are thus considered to be dumbbell tumours as described by Eden.
The incidence of dumbbell tumour is 13.7 %. The rate of all spinal cord tumours is higher in the thoracic and lumbar spine than in the cervical spine. In contrast, dumbbell tumours on the cervical spine account for 44% of all dumbbell tumours, and are more frequent than those in the thoracic and lumbar spine.
Schwannomas (69%) constitute the most common type followed by neurofibromas (12%). Neuroblastomas/ganglioneuromas (8%), meningiomas (5%), haemangiomas (2%) and miscellaneous (5%) which include angiolipoma, paraganglioma, malignant peripheral nerve sheath tumour, malignant lymphoma, melanoma, and rhabdomyosarcoma constitutes rest of the group. Schwannomas are less common under the age of 10.
Clinical features depend on the size, site and type of the tumours. Pain, weakness of limbs and sensory symptoms predominate.
Radiological investigations include X-ray, CT examination and MR. Plain X-ray reveals widening of neural foramina. CT examination can clearly show the tumour extent, however, due to multiplanar capability MR is the modality of choice, which can depict very clearly both intra and extraspinal components and help exclude pathological types. Calcification better depict in CT.
Although the actual pathogenesis, why these tumours grow in this fashion is unknown, however, it is observed that dumbbell tumours can arise either outside or inside the spinal canal or epidural or intradural spaces and extend to other regions through the foramen or root sleeve. Study reveals that tumours such as neuroblastomas and ganglioneuromas observed in paediatric patients are derived from the posterior mediastinum or retroperitoneal space and extend to the spinal canal through the foramina. Tumours such as meningiomas, located in intradural and epidural spaces are derived from the dura mater and extend into both spaces. Secondly, in tumours such as neurofibromas where multiple tumours can arise in different regions such as the paravertebral region or epidural or intradural spaces would form a dumbbell tumour by approaching each other. Finally, in dumbbell tumours of schwannomas observed in paediatric patients, the tumours might have been present before birth and might be caused by constriction from the dura mater and vertebral bone during development.
Although the majority are benign, however, malignancy is seen in a small number of cases (8.5%). Incidence of malignant dumbbell tumours is higher in children. In general, a malignant tumour adjacent to bone is likely to destroy the bone, however, malignant peripheral nerve sheath tumour like neuroblastoma, and rhabdomyosarcoma showed foraminal enlargement with sclerotic margins similar to those in benign dumbbell tumours.
Hemilaminectomy and a facetectomy is the treatment of choice for the majority of tumours. Prognosis is excellent provided the entire tumour is removed.
The incidence of dumbbell tumour is 13.7 %. The rate of all spinal cord tumours is higher in the thoracic and lumbar spine than in the cervical spine. In contrast, dumbbell tumours on the cervical spine account for 44% of all dumbbell tumours, and are more frequent than those in the thoracic and lumbar spine.
Schwannomas (69%) constitute the most common type followed by neurofibromas (12%). Neuroblastomas/ganglioneuromas (8%), meningiomas (5%), haemangiomas (2%) and miscellaneous (5%) which include angiolipoma, paraganglioma, malignant peripheral nerve sheath tumour, malignant lymphoma, melanoma, and rhabdomyosarcoma constitutes rest of the group. Schwannomas are less common under the age of 10.
Clinical features depend on the size, site and type of the tumours. Pain, weakness of limbs and sensory symptoms predominate.
Radiological investigations include X-ray, CT examination and MR. Plain X-ray reveals widening of neural foramina. CT examination can clearly show the tumour extent, however, due to multiplanar capability MR is the modality of choice, which can depict very clearly both intra and extraspinal components and help exclude pathological types. Calcification better depict in CT.
Although the actual pathogenesis, why these tumours grow in this fashion is unknown, however, it is observed that dumbbell tumours can arise either outside or inside the spinal canal or epidural or intradural spaces and extend to other regions through the foramen or root sleeve. Study reveals that tumours such as neuroblastomas and ganglioneuromas observed in paediatric patients are derived from the posterior mediastinum or retroperitoneal space and extend to the spinal canal through the foramina. Tumours such as meningiomas, located in intradural and epidural spaces are derived from the dura mater and extend into both spaces. Secondly, in tumours such as neurofibromas where multiple tumours can arise in different regions such as the paravertebral region or epidural or intradural spaces would form a dumbbell tumour by approaching each other. Finally, in dumbbell tumours of schwannomas observed in paediatric patients, the tumours might have been present before birth and might be caused by constriction from the dura mater and vertebral bone during development.
Although the majority are benign, however, malignancy is seen in a small number of cases (8.5%). Incidence of malignant dumbbell tumours is higher in children. In general, a malignant tumour adjacent to bone is likely to destroy the bone, however, malignant peripheral nerve sheath tumour like neuroblastoma, and rhabdomyosarcoma showed foraminal enlargement with sclerotic margins similar to those in benign dumbbell tumours.
Hemilaminectomy and a facetectomy is the treatment of choice for the majority of tumours. Prognosis is excellent provided the entire tumour is removed.
Differential Diagnosis List
Dumbbell tumour of cervical spine.
Final Diagnosis
Dumbbell tumour of cervical spine.
References
[1] Ozawa H, Kokubun S, Aizawa T, Hoshikawa T, Kawahara C (2007) Spinal dumbbell tumors: an analysis of a series of 118 cases. J Neurosurg Spine 7:587-93 (PMID: 18074682)
[2] Isoda H, Takahashi M, Mochizuki T, Ramsey RG, Masui T, Takehara Y et al (1996) MRI of dumbbell-shaped spinal tumors. J Comput Assist Tomogr 20(4):573-82 (PMID: 8708059)
[3] McCormick PC (1996) Surgical management of dumbbell and paraspinal tumors of the thoracic and lumbar spine. Neurosurgery 38:67-74; discussion 74-5 (PMID: 8747953)
Case information
| URL: | https://eurorad.org/case/8425 |
| DOI: | 10.1594/EURORAD/CASE.8425 |
| ISSN: | 1563-4086 |
Figure 4
Coronal MR image-T2 sequence.
Intraspinal component has significantly compressed the spinal cord from right side. The hyperintense mass is coming out between C1 and C2 arches on the right side.
Coronal MR image-T2 sequence.
Intraspinal component has significantly compressed the spinal cord from right side. The hyperintense mass is coming out between C1 and C2 arches on the right side.
