Glioblastoma multiforme of the hippocampus in advanced Alzheimer's disease

An 87-year-old woman suffered from Alzheimer's disease diagnosed 6 years prior to her death. Autopsy showed in addition to far-advanced Alzheimer's disease, a large, partially necrotic glioblastoma occupying her right hippocampus. Occurrence of a glial neoplasm in Alzheimer's disease could well be coincidental, since both entities are fairly common in elderly individuals; it is however, uncommon for gliomas to centre on the hippocampus itself. For these reasons it is possible (although cannot be proven from a single case), that florid reactive gliosis commonly associated with Alzheimer's disease, may have played a role in eventually initiating neoplastic proliferation of astrocytes in this patient.