Aggressive oligodendroglioma predicted by chromosome 10 restriction fragment length polymorphism analysis. Case study.

Oligodendrogliomas are indolent brain tumors with mean postoperative survival of about 5 years. However, the range of postoperative survivals is wide, suggesting that these tumors are heterogeneous in their biologic behavior. Using restriction fragment length polymorphism (RFLP) analysis, we studied a case of an oligodendroglioma with loss of chromosome 10 sequences, a finding that has only been reported in glioblastoma multiforme and anaplastic astrocytomas. Four and a half months after the initial surgery the patient returned with a recurrent tumor having classic radiologic and pathologic features of glioblastoma multiforme. Loss of chromosome 10 alleles in oligodendroglioma may be predictive of aggressive biologic behavior, even in the absence of recognized histopathologic characteristics of anaplasia, and may enable us to select more appropriate treatments for this group of patients.