INTRACRANIAL EPENDYMOMAS OF CHILDHOOD - LACK OF CORRELATION OF HISTOPATHOLOGY AND CLINICAL OUTCOME

The histopathology of 66 children with the diagnosis of ependymoma who were operated on at our institution between 1954 and 1994 were review ed. We performed an initial analysis using the entire study cohort to determine which histopathological features associated with each other in a statistically significant fashion in an attempt to identify combi nations of features that together might be useful in predicting outcom e. A detailed outcome analysis was then performed on the 37 most recen t cases who survived the postoperative period in whom pre- and post-im aging studies as well as long term follow-up were obtained, in order t o identify the histopathological features and combinations of features that were predictive of overall and progression-free survival. Five- and ten-year progression-free survivals were 45.1% and 36.1%, respecti vely. Overall survivals were 57.1% and 45.0%, respectively. Of the eig ht individual histopathological features, only the presence of necrosi s was found to correlate with a less favorable overall and progression -free survival (PFS) (p = 0.06 and 0.03, respectively). In addition, t he combination of necrosis with vascular proliferation or nuclear pleo morphism was associated with a worse PFS (p = 0.01 and 0.02, respectiv ely). However, when other clinical predictive factors were included in a multivariate regression analysis, none of the histological features or combinations of features were independently associated with outcom e. In addition, no relationship was found between the pattern of roset tes (true rosette, pseudorosette, or perivascular pseudorosette) and c linical outcome. In conclusion, although this study found an associati on between certain histopathological features and clinical outcome in children with ependymomas, these relationships did not reach statistic al significance on multivariate analysis and, thus, do not provide suf ficient evidence for modifying therapy based on histopathology alone.