PREDICTING DISEASE PROGRESSION IN CHILDHOOD CEREBELLAR ASTROCYTOMA

Pediatric cerebellar astrocytomas are frequently curable by complete s urgical resection. However, even incompletely resected tumors may lie dormant indefinitely or spontaneously involute, and tumors thought to be completely excised have reappeared in the same location several yea rs later. Because of the unpredictable nature of some cerebellar astro cytomas, this study was designed to analyze several variables for thei r potential value in predicting disease progression. The charts of 78 children treated at a children's hospital between 1966 and 1993 were r eviewed; 62 tumors were pilocytic, 13 were fibrillary, and 3 were mixe d oligoastrocytomas. Four children had the additional diagnosis of neu rofibromatosis type 1, and those children were considered separately. Of the remaining 74 children, 48 underwent postoperative contrast-enha nced computerized tomography or magnetic resonance imaging. Of those 4 8 children, 17 had residual disease, and in 15 cases the tumor volume could be measured. Frequently the surgeon's report conflicted with the postoperative scan regarding the presence of residual disease. Howeve r, the surgeon's report of brainstem infiltration correlated highly wi th residual disease on postoperative imaging. On univariate Cox analys is, sex, age, tumor location, and tumor morphology did not show progno stic significance. In spite of their differences, the surgeon's report of residual tumor and the presence of residual disease on postoperati ve imaging were similar in their correlation with disease progression. However, on multivariate analysis, the volume of residual tumor was m ost closely linked with disease progression. Only the presence of fibr illary histology significantly complemented the volume of residual tum or as a negative prognostic indicator.