The NICE Decision Support Unit has just published A review of studies examining the relationship between progression-free survival and overall survival in advanced or metastatic cancer, by Sarah Davis, Paul Tappenden, Anna Cantrell.
From the Executive Summary:
“Nineteen papers were included in the review covering eight different tumour types. Four studies used aggregate data from multiple trials to examine the relationship between PFS and OS for individual trial arms. Seven studies used individual patient data to examine the relationship between PFS and OS for individual patients. Thirteen studies examined the trial level relationship between treatment effect on PFS and treatment effect on OS with three using individual patient data, whilst the remainder used aggregate data from multiple trials.
A variety of statistical techniques were employed within these studies, with the most commonly used being rank correlation coefficients, linear regression and landmark analysis. The lack of a standardised approach made it difficult to establish whether there is a consistent relationship between PFS/TTP and OS. The majority of the studies found a positive correlation between PFS/TTP and OS for individual patients, individual trial arms and the treatment effect between trial arms, although, the size of the correlation and its statistical significance varied considerably across studies. This is not surprising given the variety of methods employed and the variation in studies characteristics such as differences in the tumour type and the line of therapy considered.”
As for the conclusions, you’ll have to read the report…..