progressionfree

Progressionfree, in clinical and research contexts, most commonly refers to progression-free survival (PFS). PFS is the length of time during and after a treatment in which a patient lives without the disease getting worse. In trials, PFS typically starts at randomization or treatment initiation and ends at the first documentation of disease progression or death from any cause. If a patient dies before progression is documented, that death is counted as an event in the PFS analysis.

Progression-free interval (PFI) is a related term used in some settings and may refer to the time from a defined starting point to progression, sometimes excluding death as an event depending on the study design. Disease-free survival (DFS) is distinct and generally applies after a complete response or curative intent, measuring time without recurrence after treatment, including a disease-free state rather than ongoing disease presence.

Progression is usually determined using standardized criteria, such as RECIST 1.1 for solid tumors, which define progression based on changes in tumor measurements or the appearance of new lesions. Other diseases may use alternative criteria.

PFS is a common endpoint in randomized clinical trials, especially when overall survival is prolonged or influenced by subsequent therapies. It is estimated with time-to-event methods, often presented as median PFS or as hazard ratios comparing treatment arms. Limitations include dependence on imaging schedules, potential assessment bias, and the fact that longer PFS does not always translate into improved overall survival or quality of life. Context is important when interpreting PFS results within disease and treatment paradigms.