Alzheimer disease (AD) and glioblastoma multiforme (GBM) have similar peak, age-specific incidence rates; however, to my knowledge, only 1 case of GBM associated with AD has been reported to date. The frequency of AD pathology, including neuritic plaques, diffuse plaques, neurofibrillary tangles, and cerebral amyloid angiopathy in patients with GBM is unknown. Studies of cancer occurrence in patients with AD are contradictory, with frequencies reported as equal to and as less than that in the general population. The GBM/AD nonconcordance may reflect underreporting of AD pathology or other factors.
To compare the frequency and extent of neocortical AD pathology in autopsy cases involving patients aged 60 to 82 years, both with and without GBM. Design.-Case-control study. Setting.-Pathology department of a university hospital.
Thirty-six autopsy cases of GBM patients aged 60 to 82 years; 54 cases of patients in the same age group without GBM or other primary brain tumors.
Examination of tumor sections for GBM and of neocortical sections for AD pathology according to Consortium to Establish a Registry for Alzheimer Disease (CERAD) guidelines.
Glioblastoma multiforme was confirmed in all tumor cases. Alzheimer disease pathology was present in 42% of cases with GBM and in 48% of cases without GBM; 28% of GBM cases had CERAD age-related plaque scores indicative or suggestive of AD; 43% of cases without GBM had CERAD age-related plaque scores indicative or suggestive of AD.
Alzheimer disease pathology was underreported in both GBM and non-GBM patients. The influence of neurodegenerative processes on GBM symptoms and therapy in elderly patients requires further study.