Phenotype versus genotype in gliomas displaying inter- or intratumoral histological heterogeneity.

PURPOSE: Molecular classification of gliomas is becoming increasingly important clinically as an adjunct to histopathological diagnosis. Whereas histological heterogeneity of gliomas is well recognized, less is known of the relationship between histological heterogeneity and genetic alterations. Our objective was to investigate the relationship between genotype and phenotype for markers of potential clinical utility in histologically heterogeneous gliomas. EXPERIMENTAL DESIGN: We have used laser capture microdissection to sample the various histological phenotypes present in 42 tumors from 25 glioma cases with either inter- or intratumoral histological heterogeneity, and multiple simultaneous PCR amplification of microsatellite markers and capillary electrophoresis to determine allelic imbalance in chromosomes 1p, 19q, 17p, 10p, and 10q. RESULTS: Loss of 1p36 and 19q13 was seen only in oligodendroglial histology in 7 of 13 oligodendrogliomas. 17p13 loss was found in 14 of 41 tumors in astrocytic, oligoastrocytic, oligodendroglial, and glioblastomatous histologies. Chromosome 10 loss was seen in all of the high-grade histologies in 7 of 7 glioblastomas with an oligodendroglial component and in 1 of 5 low-grade oligodendroglial regions present within high-grade tumors. Seven tumors from 5 cases had no detectable losses of any markers investigated. In 13 tumors with intratumoral heterogeneity, identical genetic losses were present in all areas of histological differentiation. Additional losses were seen in some but not all of the histologies within 2 tumors and were associated with progression in 3 cases. CONCLUSIONS: The gliomas in this study were more homogeneous in their genotype than their histological phenotype with regions of differing histological subtype indistinguishable by the genetic markers investigated, supporting a monoclonal origin of these tumors.

A 5-year study of the outcome of surgically treated depressed skull fractures.

BACKGROUND: Many changes and improvement have taken place in the management of head injured patients in the last 20 years. There have been few recent studies analysing the overall outcomes including early complications of depressed skull fractures. The aim of our study was, therefore, to examine the factors influencing the surgical outcome of patients with depressed skull fractures. METHODS: We reviewed case notes of 73 consecutive surgically treated depressed skull fractures during the period from 1 January 1994 to 31 December 1998 admitted to the Walton Centre for Neurology and Neurosurgery, Liverpool. RESULTS: There was a male preponderance of 9:1. Alleged assault was the most common cause of depressed skull fractures followed by road traffic accidents. Postoperative infection rate was 8.2%. More than 80% of patients received prophylactic antibiotics. We failed to show any statistically significant association between the use of antibiotics and reduction of the rate of infection. However, prevalence of infection was significantly associated with brain contusion, low GCS score and dural tear (P < 0.05). Prevalence of early post-traumatic epilepsy was 12.3%. No patients received prophylactic anticonvulsants. There was no significant association between dural tear and prevalence of post-traumatic epilepsy. Mortality rate was 1.4%. CONCLUSIONS: Paediatric populations have better outcome; 7 out of 10 patients in this series progressed to full recovery. Use of prophylactic antibiotics did not reduce the infection rate. Presence of dural tear was not associated with an increase risk of post-traumatic epilepsy.