Hemorrhagic intramedullary solitary fibrous tumor of the conus medullaris: case report.

The differential diagnosis of spinal tumors is guided by anatomical location and imaging characteristics. Diagnosis of rare tumors is made challenging by abnormal features. The authors present the case of a 47-year-old woman who presented with progressive subacute right lower-extremity weakness and numbness of the right thigh. Physical examination further revealed an extensor response to plantar reflex on the right and hyporeflexia of the right Achilles and patellar reflexes. Magnetic resonance imaging of the lumbar spine demonstrated an 8-mm intramedullary exophytic nodule protruding into a hematoma within the conus medullaris. Spinal angiography was performed to rule out an arteriovenous malformation, and resection with hematoma evacuation was completed. Pathological examination of the resected mass demonstrated a spindle cell neoplasm with dense bundles of collagen. Special immunostaining was performed and a diagnosis of solitary fibrous tumor (SFT) was made. SFTs are mesenchymally derived pleural neoplasms, which rarely present at other locations of the body, but have been increasingly described to occur as primary neoplasms of the spine and CNS. The authors believe that this case is unique in its rare location at the level of the conus, and also that this is the first report of a hemorrhagic SFT in the spine. Therefore, with this report the authors add to the literature the fact that this variant of an increasingly understood but heterogeneous tumor can occur, and therefore should be considered in the differential of clinically similar tumors.

Recurrent pediatric central nervous system low-grade gliomas: the role of surveillance neuroimaging in asymptomatic children.

OBJECT: Pediatric low-grade glioma (LGG) is the most common brain tumor of childhood. Except for the known association of gross-total resection and improved survival rates, relatively little is known about the clinical and radiographic predictors of recurrent disease and the optimal frequency of surveillance MRI. The authors sought to determine the clinical and radiographic features associated with recurrent or progressive disease in a single-institutional series of children diagnosed with primary CNS LGG. METHODS: The authors performed a retrospective analysis of data obtained in 102 consecutive patients diagnosed at Rady Children's Hospital-San Diego between 1994 and 2010 with a biopsy-proven LGG exclusive of a diagnosis of neurofibromatosis. Tumor location, patient age, sex, and symptomatology were correlated with tumor progression or recurrence. Magnetic resonance imaging characteristics and neuroimaging surveillance frequency were analyzed in those children with progressive or recurrent disease. RESULTS: Forty-six of 102 children diagnosed with an LGG had evidence of recurrent or progressive disease between 2 months and 11 years (mean 27.3 months) after diagnosis. In the larger group of 102 children, gross-total resection was associated with improved progression-free survival (p = 0.012). The location of tumor (p = 0.26), age at diagnosis (p = 0.69), duration of symptoms (p = 0.72), histological subtype (p = 0.74), sex (p = 0.53), or specific chemotherapeutic treatment regimen (p = 0.24) was not associated with tumor progression or recurrence. Sixty-four percent of children with recurrent or progressive disease were asymptomatic, and recurrence was diagnosed by surveillance MRI alone. All children less than 2 years of age in whom the tumor was diagnosed were asymptomatic at the time of progression (p = 0.04). Thirteen percent (6 of 46) of the children had disease recurrence 5 years after initial diagnosis; all of them had undergone an initial subtotal resection. Tumor progression was associated with either homogeneous or patchy T1-weighted post-Gd administration MRI enhancement in 94% of the cases (p = 0.0001). CONCLUSIONS: Children diagnosed with recurrent LGG may be asymptomatic at the time of recurrence. The authors' findings support the need for routine neuroimaging in a subset of children with LGGs, even when gross-total resection has been achieved, up to 5 years postdiagnosis. The authors found that T1-weighted MR images obtained before and after Gd administration alone may be sufficient to diagnose LGG recurrence and may represent an effective strategy worthy of further validation in a larger multiinstitutional cohort.