Diffuse infiltrating astrocytoma of the cervicomedullary region: clinicopathologic entity

Recent imaging and neurosurgical techniques have led to an improvement in the surgical management of children with brainstem tumors (BSTs). Many children with tumors previously considered 'inoperable' can now benefit from surgery. Increased experience has brought about new theories concerning the growth pattern, natural history, classification and optimal management of these tumors. Cervicomedullary (CM) tumors commonly have an indolent presentation reflecting either medullary or cervical spinal cord dysfunction and tend to arise in the upper cervical cord growing into the medulla in a posterior exophytic fashion. Intrinsic BSTs often present acutely with cranial nerve dysfunction and generally arise in the pons with a diffuse infiltrating growth pattern. A 21-month-old patient had developed feeding difficulty and reactive airway disease at approximately 8 months of age. MRI showed a diffuse, nonenhancing tumor in the CM region. Following radical resection, and an unremarkable perioperative course, he aspirated, developed pulmonary insufficiency and expired. Postmortem examination revealed a low-grade diffuse fibrillary astrocytoma extending from C6 to the medulla. The medullary portion arose in a paramedian location and infiltrated dorsally into the fourth ventricle, the obex, the leptomeninges, and the adjacent cerebellum. This case demonstrates the growth pattern of a distinct subset of CM tumors that behave in a manner similar to intrinsic diffuse BST. Future identification of these subsets by a careful analysis of the clinical presentation and MRI images will enable better operative planning and optimal management.