teratomas are tumors that typically , but not always contain all three germ cell layers ectoderm , mesoderm , and endoderm . teratomas are classified as mature , immature , and malignant based on the degree of differentiation . these lesions can occur throughout the spinal canal , but there is a thoracic and lumbar predominance among reported cases with the conus medullaris region being the most frequent . a 12-year - old boy was referred to our hospital with a 2 months history of back pain and 1-week history of bilateral leg weakness , urinary incontinence , and constipation . on physical examination ; he had no gross motor deficit but bilateral numbness in his legs . lumbosacral spine magnetic resonance imaging revealed a well - delineated , intramedullary , 2 cm  4 cm mass at the l1 - 2 levels of the lumbar spine . the mass was hyperintense in all sequences , and it was containing a hypointense lesion in the central zone . magnetic resonance imaging of lumbar spine ; ( a ) sagittal t2-weighted and ( b ) axial t2-weighted images showing a well - delineated , intramedullary , 2 cm  4 cm mass at the l1 - 2 levels of the lumbar spine the patient underwent an emergent surgery . the operation was performed under a surgical microscope with the assistance of intraoperative neurogenic monitoring evoked potentials . a midline incision was performed at the conus medullaris level , and a creamy , yellow - white , mucoid substance was discharged . subsequent to the evacuation of the tumor 's content , calcified solid component , and capsule was resected . however , gross total resection could not be performed because of the tenacious adhesions of the tumor to the adjacent parenchyma . after removal of the tumor , dura mater and l1 and l2 vertebrae were reconstructed . the patient had an uneventful postoperative course and his severe back pain and bilateral leg weakness improved after the surgery . now , as 1 month after surgery , the patient has no reported recurrent symptoms . ( a ) photomicrograph ( h and e , 40 ) showing connective tissue containing mucinous epithelium ( b ) photomicrograph ( h and e , 20 ) showing adipose tissue containing mature muscle cells ( c ) photomicrograph ( ihc , 40 ) showing smooth muscle cells reacted positively with actin associated anomalies such as metameric cutaneous lesions , sinus tracts , neural tube defects or split cord malformations may be present . the current classification states that a teratoma is a tumor that composed of derivatives from all 3 primitive germ layers . histologically , these lesions are divided into three categories ; mature , immature , and malignant . it is important to study the specimen completely because benign and malignant elements can be present simultaneously . magnetic resonance imaging is the most valuable diagnostic technique but , even so it can not determine with certainty the differential diagnosis between teratoma and other intramedullary lesions . the primary treatment for teratomas is surgery , and total surgical resection of the tumors should be the aim of these operations . however , as in our case gross total resection may not be possible in every operation . in a literature review made by poeze et al . , it was found that intramedullary tumors could be completely removed only in 61.8% of the reported cases . application of intraoperative electrophysiologic monitoring is important in these operations , and it is important to resect tumor as extensive as possible according to intraoperative electrophysiologic monitoring findings . removal of the tumor should be stopped when the neurological function is at risk due to the tenacious adhesions of the tumor to the adjacent parenchyma . radiotherapy is an adjuvant treatment modality that should be indicated when the tumors contain malignant components . however , adjuvant radiotherapy is not recommended for benign teratomas , and there is not any role of adjuvant chemotheraphy in the treatment of spinal teratomas .