Title: Improving the precision of oncology trials analysis using progression-free-survival as an endpoint
Authors: Chien-Ju Lin - MRC Biostatistics Unit University of Cambridge (United Kingdom) [presenting]
James Wason - MRC Biostatistics Unit University of Cambridge (United Kingdom)
Abstract: In many oncology trials, patients are followed up until progression or death and the time at which this happens is used as the efficacy endpoint. This is known as progression-free-survival (PFS). Typical analyses consider tumour progression as a binary event, but in fact it is defined by a certain change in tumour size. This additional information on continuous tumour shrinkage at multiple times is discarded. We propose a method to make use of this information to improve the precision of analyses using PFS. We use joint modelling of the continuous tumour measurement, death and progression for other reasons (such as new tumour lesions) to construct survival curves. We present how to compute confidence intervals for quantities of interest, such as the median or mean PFS. We assess the properties of the proposed method by using simulated data and real data from a real phase II cancer trial. We also showcase a R-Shiny app to implement the proposed method.