Intramedullary Spinal Cord Metastasis: A Clinical Study Of Three Patients And Review Of The Literature

Objectives:Intramedullary spinal cord metastasis(ISCM) is a rare complication of cancer.Due to both widespread MRI availability and longer survival of cancer patients,the probability of discovering an ISCM has increased.However,the number of the reports of its clinical characteristics is small.To investigate the clinical features of ISCM,three cases of ISCM of non-neurological origin were examined retrospectively.Methods:All patients were consecutively admitted in our hospital from Jan 2007 to Dec 2008 for ISCM.Inclusion criteria were as follows:adult patients over 18 having an intramedullary lesion diagnosed by MRI,and history of primary cancer originating outside the CNS and with pathologically proven tissue.Data regarding the site of the primary neoplasm,location of other metastasis,initial symptoms,interval from the original diagnosis of cancer to the onset of neurological symptoms,time course from initial symptoms to urinary retention,MRI data,and functional outcome after radiotherapy were investigated.The follow up is until Mar 2009. Results:The primary neoplasm of three patients is non-small cell lung cancer,small cell lung cancer and breast cancer respectively.The progression of neurological deficit was rapid,and the average period between the occurrence of initial symptoms and urinary retention was 23.3 days.MRI characteristics were useful for diagnosis,including isotense or hyperintense in T1-weighted images,large high signal intensity areas on T2-weighted images and homogeneous enhancement on Gd-DTPA enhanced T1-weighted images.All three patients received radiotherapy and dexamethasone,two patients improved with neurologic deficit and back pain.After the diagnosis of intramedullary spinal cord metastasis,one patient still alive after four months follow up, the other two was died after 7,4 months respectively.Conclusions:The progression of neurological deficit was rapid.MR scan after administration of gadolinium is effective to diagnosis ISCM,and radiotherapy is recommended as soon as possible after a diagnosis is made.