Recent estimates suggest that there are 2 million people in the UK living with or beyond a diagnosis of cancer and there is increasing attention being given to assessing the health and social care needs of this growing population. A simple analytical model has been constructed to estimate future trends in cancer prevalence, using existing prevalence estimates and trends in cancer incidence and survival. Separate estimates are generated for the contribution to future prevalence due to the current prevalent population and that due to future diagnoses. For the current prevalent population, we adopt a conditional survival model incorporating time since diagnosis in addition to age, tumour type and other factors. We discuss the analytical framework that has been constructed and its intended use in providing information that is useful to those planning health and social care services.