Benign cerebellar astrocytomas in children

Object. Cerebellar astrocytomas are benign tumors of childhood known to be associated with excellent long-term survival in patients in whom complete s urgical resection is possible. However, the roles of other factors-clinical , radiological, histological, and therapeutic-in the survival of the patien t, tumor recurrence, and long-term patient outcome remain imprecise. The go al of this study was to examine these factors and their relationships. Methods. To clarify these issues a retrospective review was conducted of 16 8 children who were surgically treated for a cerebellar astrocytoma at Hopi tal Necker-Enfants Malades between 1955 and 1995. These patients' clinical files were examined, the histological characteristics of their tumors were reviewed, and their outcomes were assessed according to Bloom's scale and t he Wechsler intelligence quotient test. Of the 168 patients in the study, 91 were male and 77 were female with a me an age of 6.9 years and a mean follow up lasting 7.7 years. Tumors were ide ntified as being strictly located in the cerebellum in 76.2% of the patient s and as involving the brainstem (referred to as the "transitional form") i n 23.8% of the patients. Complete surgical excision was possible in 88.7% o f cases. There was a total mortality rate of 4.2% and a tumor recurrence ra te of 9.5%. Fifty-eight percent of the patients had no neurological sequela e at follow-up evaluation. Pejorative factors that were discovered by multivariate analysis to be impo rtant included: a long preoperative duration of symptoms and the transition al form of tumor with respect to survival; incomplete tumor excision with r espect to an increased risk of recurrence; and a long preoperative duration of symptoms, an early epoch during which surgery was performed (1955-1974) , severe ventricular dilation, and the transitional form of tumor with resp ect to a poorer long-term patient outcome. Conclusions. The presence of brainstem involvement (tumor in the transition al form) emerged as a significant negative prognostic factor and should be treated as a distinct nosological entity. The extent of surgical excision h as a significant bearing on the risk of tumor recurrence.