PET Imaging in MCI Following ADT for PCa

Mild cognitive impairment (MCI) with ageing is thought in part to be related to reduced serum sex hormones which is well-recognized, especially in females, but poorly understood. International studies assessing hormone replacement therapy (HRT) to prevent/reduce MCI are ongoing. MCI leads to morbidity, reduced quality of life and substantial healthcare costs. The commonest therapeutically induced reduction in sex hormone level in men is treatment of prostate cancer (PCa). PCa is androgen dependent and androgen deprivation therapy (ADT) suppressing testosterone to castrate levels is key therapy for advanced disease. About one million men worldwide have received ADT for PCa, mostly using luteinising hormone releasing hormone agonists (LHRHa) although oral oestrogens were used in the past; eventually perhaps 4% of Caucasians may be castrated. MCI as a side effect of castration in men remains poorly researched. This study aims to demonstrate that pathological changes occur in the brains of a significant proportion of prostate cancer patients subjected to ADT that correlate with MCI symptoms. Highlighting the pathological changes of MCI should improve understanding and interventions for slowing/preventing MCI in PCa survivors. Brain scans employing positron emission tomography (PET) imaging technique will be used to detect the presence of pathological changes in the brain that relate to ADT induced MCI. MCI will be assessed by neuropsychological assessments (standard paper-based questionnaires and online) and its neural basis will be investigated using magnetic resonance imaging (MRI).