Posterior Fossa Neoplasm and PHACES Syndrome A Case Report KatharineE. Wallen, MD,* EldadJ. Hadar, MD,w Victor Perry, MD,w ThomasW. Bouldin, MD,z James Loehr, MD,y and Julie Blatt, MD* Summary: A 4-year-old girl with PHACES syndrome (posterior fossa brain malformations, hemangiomas, arterial anomalies, cardiac anomalies/coarctation of the aorta, eye abnormalities, and sternal clefting/supraumbilical raphe) developed a cerebellar pilocytic astrocytoma 18 months after resolution of her neck, ear, and thoracic hemangiomas. Because cutaneous hemangiomas may have involuted by the time a patient is diagnosed with a central nervous system neoplasm, it seems possible that in other such patients the association may have gone unrecognized. Cerebellar pilocytic astrocytoma may be a rare manifestation of the posterior fossa malformations of PHACES. Key Words: brain neoplasm, PHACES, vascular malformation (J Pediatr Hematol Oncol 2009;31:203–205) T he constellation of posterior fossa brain malformations, hemangiomas, arterial anomalies, cardiac anomalies/ coarctation of the aorta, eye abnormalities, and sternal clefting/supraumbilical raphe, denoted PHACES syn- drome, represents a subset of patients with infantile hemangiomas. 1,2 The intracranial abnormalities of PHACES are 2-fold: congenital anomalies including structural mal- formation of the cerebrum, cerebellum, and cerebral vasculature and progressive stenosis of key cerebral arteries. 3 The most common structural malformation is Dandy-Walker syndrome, found in up to 81% of patients with PHACES syndrome. 4 We describe a 4-year-old girl with PHACES syndrome who developed a cerebellar pilocytic astrocytoma, and believe this to be the first reported case of an intracranial neoplasm in a patient with PHACES syndrome. CASE DESCRIPTION A 4-year-old white female presented with 6 months of unsteady gait, head tilt, and increasing headaches. Head computed tomographic and magnetic resonance imaging scans demonstrated a 4.4  4.3 cm posterior fossa mass centered in the fourth ventricle with resulting obstructive hydrocephalus (Fig. 1). The mass was isointense on T1 and hyperintense on T2, and demonstrated heterogeneous postcontrast enhancement. The patient underwent craniectomy and gross total resection of the mass. Pathology confirmed a diagnosis of cerebellar pilocytic astrocytoma (Fig. 2). The child had been a 3.8 kg full-term baby with known ventricular septal defect. Bronchoscopy and chest magnetic resonance imaging at the age of 6 months for evaluation of stridor demonstrated bilateral intrathoracic hemangiomas extend- ing into the apex of the right hemithorax and left mediastinum, right aortic arch with coarctation, and aberrant left subclavian artery. History also was notable for bilateral neck hemangiomas and hemangiomas on the back of her neck and left external ear. Although magnetic resonance angiography (MRA) of the chest was performed as part of planning for cardiac surgery, no MRA of the brain was performed. Follow-up computed tomographic scans 2 1 = 2 years after this surgery and before diagnosis of her brain tumor demonstrated complete spontaneous resolution of the hemangiomas. FIGURE 1. Transverse T2-weighted magnetic resonance imaging scan depicting a large mass centered in the fourth ventricle with resulting obstructive hydrocephalus. Copyright r 2009 by Lippincott Williams & Wilkins Received for publication August 8, 2008; accepted November 18, 2008. From the *Divisions of Hematology Oncology; wNeurosurgery; yCardiology; and zDepartments of Pediatrics and Pathology/ Laboratory Medicine, The University of North Carolina, Chapel Hill, NC. No financial support was received for the production of this case report. Reprints: Katharine E. Wallen, MD, Division of Pediatric Hematology Oncology, Room 1106, 170 Manning Drive, University of North Carolina, Chapel Hill, NC 27599-7236 (e-mail: kwallen@unch. unc.edu). CLINICAL AND LABORATORY OBSERVATIONS J Pediatr Hematol Oncol  Volume 31, Number 3, March 2009 203