Acta Neurochir (Wien) (2004) 146: 195–197 DOI 10.1007/s00701-003-0166-3
Brief Report of Special Case Spinal epidural rhabdomyosarcoma Z. Rumboldt1 , H. Jednacˇak2 , J. Talan-Hranilovic´3 , and V. Kalousek1 1
Department of Radiology, University Hospital ‘‘Sisters of Mercy’’, Zagreb, Croatia Department of Neurosurgery, University Hospital ‘‘Sisters of Mercy’’, Zagreb, Croatia 3 Department of Pathology, University Hospital ‘‘Sisters of Mercy’’, Zagreb, Croatia 2
Published online December 9, 2003 # Springer-Verlag 2003
Summary We report an extremely rare case of rhabdomyosarcoma in the lower cervical and upper thoracic spine. The MR imaging appearance of the lesion was nonspecific, and different from the one previously reported. The majority of the tumor was removed surgically less than a month from the onset of symptoms. Treatment was continued with spinal irradiation and chemotherapy, however diffuse leptomeningeal metastases were found six months later. Keywords: Spinal tumour; rhabdomyosarcoma; MRI.
Case report A 6-year-old boy developed pain in his right arm after playing in the snow for a couple of hours. The pain persisted for about a week, when torticollis also occured. Ten days later, the worsening arm pain and torticollis were accompanied with ambulation problems and right arm weakness. On admission, three days later, the boy could hardly walk. Clinical examination revealed a moderate paraparesis, reduced motor strength and pain in the right arm, which was increasing in intensity with arm flexion. There were no sensory deficits. A non-enhanced cervical spine CT study showed slightly widened C6–C7 neural foramen on the right. On MR imaging an epidural mass spreading from C5 to T2 was found (Fig. 1). The lesion was filling the anterior and posterior epidural spaces, displacing the spinal cord to the left, and extending through the C6–C7 neural foramen on the right. The mass was of homogenous appearance on all pulse sequences, with low signal intensity on T1-weighted images, high signal intensity on T2weighted images, and marked homogenous contrast enhancement (Fig. 1). Surgery was performed two days after admission, and 23 days after the onset of first symptoms. Laminectomy from C5 to T2 vertebrae was carried out, and a highly vascularized soft tumour loosely connected to the dura was encountered. Total excision of the tumor in the epidural space of the spinal canal was performed. However, a portion of the lesion, estimated at 10% of the total volume, which extended through the right C6–C7 neural foramen, was left intact. A densely cellular neoplasm, consisting of poorly differentiated cells of myoblast type with very high mitotic index was demonstrated on
histology (Fig. 2). Myxoid areas were also found, and on immunohistochemistry the tumour cells were strongly reactive to myoglobin (Fig. 3), and non-reactive to desmin. The diagnosis of rhabdomyosarcoma, embryonic subtype, was made. The patient’s arm pain and torticollis were less severe postoperatively, and paraparesis slowly started to improve. Further work-up, including chest CT and nuclear bone scan, showed no evidence of metastatic disease. The patient underwent spinal irradiation and chemotherapy, with 8 cycles of vincristine and dactinomycine. Over the following months he fully recovered from paraparesis and was free of pain and torticollis. Motor strength of the right arm improved, but not completely. Follow-up MR imaging obtained six months after surgery showed leptomeningeal tumor spread along the spinal cord and cerebellum (Fig. 4). This finding was soon followed by gradual relapse of neurological deficit. Seven months after surgery the patient was tetraparetic and somnolent, and a posterior fossa mass was detected on a CT study. Despite partial decompression of the mass and shunt placement, the patient’s condition further deteriorated and he expired two weeks later.
Discussion The vast majority of extradural spinal tumors are metastases from other organs [1, 3]. Most of the primary neoplasms arising within the spinal epidural space are lymphomas, meningiomas, nerve sheath tumors, and haemangiomas. Cases of angiomyolipoma and Ewing sarcoma have also been reported [2]. To our knowledge, there has been only one previous report describing MR imaging findings of a spinal epidural rhabdomyosarcoma [5]. That tumour developed in a 52-year-old patient, and was hyperintense on nonenhanced T1weighted images, presumably due to haemorrhage [5]. This is different from our case, which demonstrated nonspecific MR imaging findings.
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Fig. 1(a). Preoperative axial T1-weighted image at the C6–C7 level shows a homogenous mass isointense to the muscle in the anterior and posterior epidural space. The mass displaces the spinal cord to the left, and extends through the C6–C7 neural foramen on the right. (b) Preoperative sagittal contrast-enhanced T1-weighted MR image shows a homogenously enhancing lesion anterior and posterior to the spinal cord, extending from C5 to T2
Fig. 2(a). Photomicrograph shows a densely cellular neoplasm with hyperchromatic round and ovoid cells of myoblast type. Numerous mitoses are seen on this slide, and 19 mitoses were detected per 10 high power fields (H-E, original magnification 400). (b) Photomicrograph shows some eight cells that are staining very intensely on immunohistochemistry for myoglobin. The remaining cells demonstrate small amounts of staining in the cytoplasm surrounding the nucleus (original magnification 400)
Rhabdomyosarcoma is thought to arise from primitive mesenchymal cells committed to skeletal muscle differentiation, and can occur in any part of the body, except bone, including areas that lack striated muscle [2, 3]. It is the most common soft-tissue sarcoma of childhood, and in 78% of the cases occurs before 12 years of age [2, 3]. It predominantly arises in the head and neck, with embryonal rhabdomyosarcoma being the most common histologic subtype. Recently described grape-like con-
trast enhancement has been named ‘‘botyroid sign’’, and it appears to be a relatively common finding in head and neck rhabdomyosarcomas, particularly in children [4]. This enhancement pattern was not observed in the case presented. In conclusion, when an epidural spinal mass with nonspecific imaging findings is found, rhabdomyosarcoma should be included in differential diagnosis, and total excision, which is the preferred treatment, should be attempted.
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2. Hagiwara A, Inoue Y, Nakayama T et al (2001) The ‘‘botryoid sign’’: a characteristic feature of rhabdomyosarcomas in the head and neck. Neuroradiology 43: 331–335 3. McCarville MB, Spunt SL, Pappo AS (2001) Rhabdomyosarcoma in pediatric patients: the good, the bad, and the unusual. AJR 176: 1563–1569 4. Shin JH, Lee HK, Rhim SC, Cho K-J, Choi CG, Suh DC (2001) Spinal epidural extraskeletal Ewing sarcoma: MR findings in two cases. AJNR 22: 795–798 5. Tsitsopoulos PD, Tsonidis CA, Nananis KA, Tsoleka KD, Tavridis GN (1995) Unusual course of an epidural rhabdomyosarcoma of the upper thoracic spine. Acta Neurochir (Wien) 135: 198–200
Comment
Fig. 3. Sagittal contrast-enhanced T1-weighted MR image from the follow-up study shows enhancement of the entire surface of the spinal cord and vermis, consistent with leptomeningeal tumor spread
This is a short well-illustrated case report on a very rare and aggressive illness. In spite of subtotal removal, radiation therapy and chemotherapy, the illness progressed within 6 months with lepto-meningeal spread and posterior fossa mass. Subarachnoid seeding from an epidural lesion is uncommon. We would have liked to find in the discussion some comments from the authors about the physiopathological mechanisms explaining such a phenomenon and the rate of occurrence in malignant epidural lesions. Jaques Brotchi
References 1. Dunn RC Jr, Kelly WA, Wohns RN, Howe JF (1980) Spinal epidural neoplasia. A 15-year review of the results of surgical therapy. J Neurosurg 52: 47–51
Correspondence: Zoran Rumboldt, M.D., Medical University of South Carolina, Department of Radiology, 169 Ashley Ave, P.O. Box 250322, Charleston, SC 29425, U.S.A. e-mail:
[email protected]
