Clinical utility of fluorescence in situ hybridization (FISH) in morphologically ambiguous gliomas with hybrid oligodendroglial/astrocytic features.

摘要: Gliomas with hybrid oligodendroglial/astrocytic features are diagnostically problematic, and our ability to predict tumor behavior is limited. Some likely represent intermingled mixed oligoastrocytomas (MOAs), though precise diagnostic criteria specific markers for this lesion lacking. From the files at Washington University (1987-2000), 155 "ambiguous" glioma/intermingled MOA candidates were independently classified graded by 5 neuropathologists, consensus-derived pure oligodendrogliomas astrocytomas excluded from further study. The 90 remaining cases (grades II = 29, III 44, IV 17) analyzed FISH on formalin-fixed, paraffin-embedded sections. Detectable deletions included combined 1p/19q (9%), solitary 19q (22%), PTEN/DMBT1 (26%), p16 (32%). EGFR amplification was found in 11%. Patients followed until death (47%) or a median of 3.3 years. Similar prior glioma series, patient age (p < 0.0001) grade strongly associated survival times. 0.0007) PTEN/ DMBT1 0.016) 0.014), either individually as group 0.04), portended shorter compared tumors lacking these alterations. We conclude that 1) distinct genetic subsets identifiable morphologically ambiguous gliomas, 2) both histological grading molecular analysis yield prognostically useful information.