Disease-free survival, or DFS for short, is a time-to-event endpoint primarily used for adjuvant treatment after potentially curative local therapy, not for typical metastatic disease. It measures the time to recurrence of the disease or death. DFS therefore indicates how long people remain free of documented relapse after initial treatment.<\/p>\n
The EMA lists DFS as a possible primary efficacy endpoint in the adjuvant setting. This requires a precise definition of what counts as relapse or an event. In curatively treated disease, this may be a local, regional, or distant recurrence; the exact event definition depends on the tumour type and the protocol.<\/p>\n
Time measurement requires a clearly defined starting point, such as randomisation or the start of adjuvant therapy. The protocol also specifies how death without a previously documented relapse is handled and which assessments determine disease status. DFS is therefore not simply the proportion of relapse-free individuals at a given cut-off date, but a longitudinal analysis with censoring rules.<\/p>\n
DFS analysis takes into account when relapses and deaths occur. Differences between groups should be presented with effect size, confidence interval, number of events, and duration of follow-up. A low number of events or unequal follow-up can limit interpretability. In the context of PFS and DFS, the EMA emphasises the methodological need to define the endpoint definition and the imaging and\/or assessment strategy unambiguously in advance.<\/p>\n
For a benefit\u2013risk assessment, a DFS difference is not sufficient in isolation from the clinical context. The type and site of relapse, subsequent treatments, safety, and overall survival data can change the interpretation. The endpoint reflects recurrence of the disease, but not symptom burden or quality of life after adjuvant treatment on its own.<\/p>\n
The difference between DFS and progression-free survival (PFS) lies first in the treatment setting: DFS is used after curative initial therapy in the adjuvant setting, whereas PFS is typically used in measurable advanced or metastatic disease. PFS captures progression or death, while DFS tracks relapse of a previously treated disease or death.<\/p>\n
Overall Survival measures the time to death from any cause and is therefore not identical to either DFS or PFS. DFS can make a clinically relevant effect visible earlier, but it does not automatically indicate overall survival time. The overall-survival entry explains this endpoint; the present term focuses on the relapse-free interval after curative treatment.<\/p>\n
The adjuvant setting requires particularly careful event definition because, after curative treatment, baseline findings are not present as measurable tumour burden. A local recurrence, a distant recurrence, a second primary disease, or death may have different implications for endpoint logic depending on the indication. The EMA appendix on DFS and PFS underscores that such decisions must not be adjusted after reviewing the results. They must be specified before study start in the protocol and the statistical analysis plan. The question of whether relapse assessment is independently reviewed can also be relevant when the event time point may be subjectively influenced. A robust DFS analysis therefore makes the event distribution and the assessment process transparent.<\/p>\n
Unlike a cross-sectional statement of disease status, DFS accounts for the fact that participants are followed up for different lengths of time. Individuals without a documented event by the data cut-off date contribute their available observation time to the analysis. As with other time-to-event endpoints, the handling of losses to follow-up must be defined in advance and reported. Incomplete follow-up can make relapses unevenly detectable, particularly in the adjuvant setting.<\/p>\n
For DFS studies, standardised follow-up intervals and a verifiable relapse definition are essential. Differences between centres in imaging, pathological confirmation, or work-up of suspicious findings can shift the timing of the DFS event. The protocol, eCRF, and statistical analysis plan must therefore reflect the same event categories, date rules, and censoring principles.<\/p>\n
Full-service CROs such as Mediconomics support the development of the DFS definition in the protocol and alignment with the visit schedule and imaging requirements. They set up data checks for recurrence findings, support monitoring of follow-up, and coordinate biostatistics and medical writing to transparently present event types, follow-up, DFS analysis, and overall survival data.<\/p>\n
Is DFS the usual endpoint for metastatic disease?<\/strong><\/p>\n No. In metastatic or advanced disease, PFS is often used because a baseline state without detectable disease after curative therapy is not present.<\/p>\n Does a death without documented recurrence count as a DFS event?<\/strong><\/p>\n The EMA definition includes time to recurrence of the disease or death. The specific implementation must be specified in the protocol for the respective study.<\/p>\n Is longer DFS equivalent to longer Overall Survival?<\/strong><\/p>\n No. The two endpoints capture different events. An observed DFS difference must be interpreted together with the available overall survival and safety data.<\/p>\n Disease-free survival, or DFS for short, is a time-to-event endpoint primarily used for adjuvant treatment after potentially curative local therapy, not for typical metastatic disease. It measures the time to recurrence of the disease or death. DFS therefore indicates how long people remain free of documented relapse after initial treatment. Endpoint in the adjuvant setting […]<\/p>\n","protected":false},"author":10,"featured_media":0,"parent":0,"template":"","meta":{"_acf_changed":false,"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"glossary-cat":[30],"class_list":["post-8147","glossary","type-glossary","status-publish","hentry","glossary-cat-atmp-onkologie"],"acf":[],"related_terms":"","external_url":"","internal_reference_id":"","_links":{"self":[{"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/glossary\/8147","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/glossary"}],"about":[{"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/types\/glossary"}],"author":[{"embeddable":true,"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/users\/10"}],"version-history":[{"count":0,"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/glossary\/8147\/revisions"}],"wp:attachment":[{"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/media?parent=8147"}],"wp:term":[{"taxonomy":"glossary-cat","embeddable":true,"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/glossary-cat?post=8147"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Regulatory references<\/h2>\n
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