Von Hippel-Lindau disease germline mutations in Mexican patients with cerebellar hemangioblastoma

OBJECT: Central nervous system (CNS) hemangioblastomas are benign vascular tumors arising either sporadically or as a manifestation of von Hippel-Lindau (VHL) disease, a hereditary cancer syndrome. The authors studied a series of patients with CNS hemangioblastomas and their families to identify germline mutations in the VHL tumor suppressor gene and to establish a predictive testing and screening protocol. METHODS: Patients admitted between 2002 and 2004 to the Instituto Nacional de Neurología y Neurocirugía for hemangioblastoma were prospectively enrolled, together with their at-risk family members. The authors performed the molecular analysis of the VHL gene by using polymerase chain reaction and direct genetic sequencing. All asymptomatic mutation carriers underwent genetic counseling and tumor surveillance. Ninety-eight individuals were tested for VHL mutations--23 symptomatic and 75 asymptomatic individuals belonging to 16 families. Seven of the families had definite clinical criteria of VHL disease, five had sporadic hemangioblastoma, and four had CNS hemangioblastoma combined with minor visceral signs. Molecular genetic testing identified five germline mutations in six of the definite VHL families (sensitivity 85%), but none in the possible VHL and sporadic hemangioblastoma cases; four of these mutations had been previously described and one is a novel mutation present in two unrelated families. After patients carrying the mutation were identified, they underwent clinical screening and asymptomatic VHL-related lesions were identified in 43%. CONCLUSIONS: Genetic testing for mutations in the VHL gene is crucial in patients with CNS hemangioblastoma. The prompt identification of patients carrying the genetic mutation allows for a multidisciplinary screening protocol to decrease morbidity and mortality rates in these patients, while avoiding costly and invasive procedures for noncarriers.