Background: Cognitive deficits are the hallmark of dose limiting late radiation morbidity in the CNS. Little is known about the neuropsychometric morbidity of treatment in adults with primary brain tumours. We set out to evaluate systematically the neuropsychometric function of all long-term survivors in order to document the frequency and severity of impairment and study its relationship with tumour and treatment related parameters.
Materials and methods: 30 patients surviving in clinical and radiological remission for > 4 years following irradiation were recalled for clinical examination, CT/MRI scan and neuropsychometric testing. The 14 males, 16 females, (mean age 42.5 years), represented all but one long term survivors treated with radiotherapy in the Department of Clinical Oncology between 1971 and 1990. Twenty-five patients had a histological diagnosis of glioma. Patients treated before 1987 (n = 16) received whole brain irradiation (WBI); focused irradiation (FI) has been used since (n = 14).
Results: The two groups were similar were in age, initial tumour type and surgical treatment, but the WBI group showed more evidence of neuropsychometric impairment than the FI group with significantly lower group median scores in tests of visuospatial organisation (WAIS Block Design, P = 0.01), visual memory (Rey Complex figure, P = 0.003) and complex information processing (Trails A, P = 0.003; Trails B, P = 0.002). Pre-morbid IQ estimated from sociodemographic variables, was comparable in the 2 groups which were not significantly different in their emotional state as assessed by the HADS. On univariate analysis radiation volume (P = 0.05) and time from treatment (P = 0.02) were the main factors associated with neuropsychometric deficit. Multivariate analysis by logistic regression confirmed WBI as the only independent predictor of neuropsychometric impairment (WBI vs. FI, odds ratio = 7.1, 95% C.I. 1.2-42.3, P = 0.03).
Conclusions: Neuropsychometric deficits are common and can be related to time from treatment and radiation technique. Neuropsychometric testing can be a useful tool in the evaluation of different treatment strategies.