Abstract

Prostate cancer is the leading cause of cancer death in men after skin cancer, with an incidence expected to double by 2030 mainly due to the ageing population. However, many more men die with prostate cancer rather than from the disease, highlighting the indolent nature of many tumours. Therefore, the development of non-invasive imaging methods to stratify prostate cancer is important for patient management.

Recently, multiparametric MRI has revolutionised the work-up of prostate cancer, becoming a routine part of clinical practice and migrating earlier in the diagnostic pathway. However, the technique remains challenging, with patient-related factors, intrinsic insensitivity of MRI, protocol differences, and radiologist experienced all combining to limit its overall accuracy. Anatomical T2-weighted imaging is limited by the non-specific nature of its findings and improvements have mainly been driven by the addition of functional sequences such as diffusion-weighted imaging, dynamic contrast-enhanced MRI and spectroscopy. In the absence of validated circulating biomarkers, only functional imaging currently offers the potential for further improvements in lesion detection and characterisation, with the additional advantages of providing whole gland coverage of the prostate and being non-invasive.

This thesis addresses the issues of prostate tumour localisation and characterisation using functional imaging techniques. Chapter 2 assesses whether simple pre-imaging interventions relating to patient preparation can help improve MRI quality. Chapter 3 evaluates the potential for two novel functional MR sequences to differentiate tumour from normal prostate tissue. Chapter 4 investigates whether non-proton sodium MRI can offer functional information reflecting cell membrane integrity and cell viability. Chapter 5 evaluates whether the PET/CT tracer 11C-acetate can offer additive information on primary prostate tumours.

Tristan Barrett