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Paper text:
spinal chondrosarcoma is an extremely rare malignant tumor , characterized by cartilage - forming9 ) .
chondrosarcomas compose 7% to 12% of all primary spine tumors and one forth of primary malignant spine tumors2 ) . in the spine ,
the common site of chondrosarcoma is the thoracic spine , followed by lumbar and cervical spine3 ) .
growth pattern of chondrosarcoma is usually indolent , and the most common presenting symptom is focal pain6,15 ) .
there is no previous reported case of spinal chondrosarcoma , which is presented with sudden progressive paraplegia , due to acute hemorrhage and exophytic expansion into the epidural space .
we named it chondrosarcoma apoplexy because it is a similar condition with that of the pituitary apoplexy , which causes neurological problems , such as visual loss .
twelve hours prior to such paraplegic event , he visited an outpatient clinic . at that time
, he just complained of discomfort and tenderness around the medial border of the right scapular , and his neurologic statue was absolutely intact .
as such , he wanted to make another visit later when he would develop aggravated pain .
there was no evidence of increased uptake on the pet - ct scan that he has checked two years ago .
magnetic resonance imaging ( mri ) checked at the emergency room showed a lobulated soft tissue mass from t3 to t5 , which extended to the epidural space ( fig .
computed tomography scans showed soft tissue mass on the spinal posterior arch and osteolytic change of the adjacent bony structures ( fig .
dark reddish blood and gel - like material were encountered around the dura and posterior arch during the operation .
3 ) . the results of immunohistochemical stains for the high grade spindle cells were focal ( + ) for smooth muscle actin antibody , but ( - ) for desmin , cytokeratin , cd34 and s-100 protein .
multiple pulmonary nodules were found on chest ct scan , and biopsy of one of them had proven to be a metastasis of chondrosarcoma .
spinal chondrosarcomas are uncommon disorders , characterized by malignant cartilage - forming and most commonly arise in the thoracic region3,9,10 ) .
chondrosarcomas compose 7% to 12% of all primary spinal bone tumors and one forth of primary malignant spine tumors2 ) . affected ages are usually forth to sixth decades2 ) .
although the most common presenting symptom is focal pain , neurologic deficits are also common3,8,10,15 ) .
plain radiography , ct scan and mri are useful to assess the location and characteristics of the tumor .
ct scan typically demonstrates a lytic , destructive lesion of various densities , with or without focal bony expansion6,13 ) .
cortical thickening with extension to the soft tissue can be seen in peripheral chondrosarcoma , a round lytic lesion with surrounding sclerosis is observed in a clear cell chondrosarcoma4 ) .
the most common mri patterns are low signal intensity with t1 and high signal intensity lesion with t2 weighted images , peripheral or heterogeneous enhancement with gadolinium6 ) .
chondrosarcomas are classified into several subtypes , which include the conventional , clear cell , mesenchymal and dedifferentiated types6,8,9,11 ) . according to the pathology , conventional chondrosarcomas are mostly benign and dedifferentiated chondrosarcomas are aggressive and frequently metastasize to other sites12 ) .
chondromas and other sarcomas , including osteosarcoma , leiomyosarcoma , and rhabdomyosarcoma , should be considered as differential diagnosis3 ) .
the goal of the treatment is to excise the lesion as completely as possible15 ) .
although these tumors are resistant to adjuvant chemotherapy and radiotherapy , hypofractionated stereotactic radiation therapy may be useful for tumor recurrence and palliation5 - 7,11 ) . in our case ,
the mass was located mainly in the posterior arch of t3 and t4 , t5 and extended to the epidural space .
there is no previous reported case of spinal chondrosarcoma that is presented with sudden progressive paraplegia , due to acute hemorrhage and exophytic expansion into the epidural space .
we named it chondrosarcoma apoplexy because it is a similar condition with pituitary apoplexy that causes acute visual loss .
chondrosarcoma is an uncommon disorder that rarely involves the spine and previously has never been associated with sudden paraplegia with acute hemorrhage and expansion into the epidural space . when radiologic studies show a lobulated mass with extension into the surrounding tissue and osteolytic change , chondrosarcoma should be included in the differential diagnosis of primary spinal bone tumor ,
although its occurrence at this site is extremely rare . furthermore , we should realize the possibility of hemorrhage and sudden expansion when the patient 's neurologic deficit developed suddenly .
chondrosarcoma is a very uncommon malignant primary bone tumor , especially , it occurs extremely rare in the spine . 
 a 52-year - old man was admitted to the emergency room with sudden paraplegia . 
 twelve hours prior to a paraplegic event , he visited an outpatient clinic with discomfort and tenderness around the medial border of the right scapular , and his neurologic status was absolutely intact . 
 magnetic resonance imaging showed a lobulated soft tissue mass from t3 to t5 , which extended to the epidural space . 
 computed tomography scans showed soft tissue mass on the spinal posterior arch and osteolytic change of the adjacent bony structures . 
 emergent surgery was performed and the lesion was removed . 
 dark reddish blood and gel - like material were encountered around the dura and posterior arch during the operation . 
 multiple pulmonary nodules were found on a chest ct scan and a biopsy of one of them had been proven to be a metastasis of chondrosarcoma . 
 the histologic examination showed dedifferentiated chondrosarcoma . 
 the patient 's neurologic deficit was improved slowly from asia a to asia d. chondrosarcoma in the spine is extremely rare , even more with acute hemorrhage and sudden expansion into the epidural space . 
 we named it chondrosarcoma apoplexy . 
 we should consider the possibility of a hemorrhagic event when the patient 's neurologic deficit worsens suddenly with spinal bone tumor .