Development-free survival (PFS) is a surrogate endpoint is outlined as follows (by ChatGPT):
In essence, PFS refers back to the size of time throughout a scientific examine or therapy routine the place a affected person’s illness doesn’t worsen or progress. As an example, in most cancers analysis, it measures the time from the beginning of therapy till the most cancers exhibits indicators of progress, unfold, or relapse.
Understanding PFS is important as a result of it helps clinicians and researchers assess the effectiveness of a therapy in controlling the illness. An extended PFS means that the therapy is efficiently slowing down the development of the sickness. This metric is especially vital in scientific trials when evaluating totally different therapy approaches or medicine.
A key query is, do sufferers care about PFS? The reply could also be sure, as a result of higher PFS is most frequently (however not all the time) correlated with longer survival. Nevertheless, do sufferers worth PFS impartial of OS? Maybe so if their high quality of life is healthier (i.e., they’ve fewer signs) in the course of the pre-progression section. Or, maybe they’ve decrease nervousness in the event that they know their most cancers has not progressed.
What does the literature say?
A paper by Raphael et al. (2019) performed a scientific literature evaluate of research that consider whether or not sufferers with superior most cancers perceive and worth PFS. General, 17 research met their inclusion standards. Of those:
Ten research particularly offered sufferers with the time period progression-free survival as an attribute selection. Within the phrases used to outline the attribute of PFS, 6 research used the time period survival. 5 research clarified that PFS might not translate into higher total survival, and 5 research defined that enhancements in PFS might not mirror how properly the affected person might really feel. No examine clarified {that a} PFS occasion may characterize both development or demise, and no examine outlined for the affected person what constituted development. The research assessed herein underrepresented ethnic and racial minorities (imply share of white sufferers, 88%; vary, 77%-96%). Values and preferences might fluctuate throughout cultural backgrounds on condition that totally different relative preferences have been assigned to value and efficacy outcomes in North American vs Asian research, though just a few research have been evaluated.
As you possibly can see from the desk beneath, there’s vital heterogeneity by way of how PFS was offered to the most cancers affected person respondents.
In a number of the research, PFS was crucial attribute. In others, high quality of life elements have been extra vital. General, nevertheless, it’s clear that extra analysis is required to completely perceive how sufferers understand the worth of PFS.