disease-free survival
Also written as: DFS — Disease-Free Survival
Time from treatment completion or surgical resection until cancer recurrence or death, commonly used in adjuvant therapy studies.
Full Definition
Disease-free survival (DFS) measures the time from treatment completion (typically surgery or definitive therapy) until the first occurrence of cancer recurrence, development of a new primary cancer, or death from any cause, whichever occurs first. This endpoint is particularly important in adjuvant treatment studies where patients have undergone primary therapy with curative intent and are receiving additional treatment to prevent recurrence. DFS provides earlier readouts than overall survival and is often used as a primary endpoint in adjuvant clinical trials. However, DFS definitions can vary between studies, particularly regarding what constitutes recurrence (local, regional, or distant) and whether second primary cancers are included, requiring careful interpretation and standardized definitions for meaningful comparisons.
Usage
Usage note: Clearly define what events are included in DFS analysis; distinguish from progression-free survival which applies to metastatic settings.
In Context
- "The five-year disease-free survival rate was 78% in the adjuvant treatment group." — Clinical trial results
- "Disease-free survival analysis requires careful definition of recurrence criteria and follow-up schedules." — Study protocol