RFS = Relapse-Free Survival (or Recurrence-Free Survival)
Definition
- The length of time after primary treatment (e.g., surgery, radiation, systemic therapy) during which a patient survives without signs or symptoms of the cancer returning (relapse/recurrence).
- Measured from the date of complete remission or curative-intent treatment to the date of documented recurrence or death from any cause (depending on the trial definition).
Why It’s Important
- Endpoint in clinical trials: Often used in adjuvant therapy trials, especially in breast, melanoma, colorectal, and lung cancers.
- Serves as a surrogate endpoint for overall survival (OS), since recurrence often occurs before death.
- Helps assess whether an intervention delays or prevents the return of cancer.
Difference from Related Terms
- DFS (Disease-Free Survival): Very similar; sometimes interchangeable. Some groups define DFS more broadly (includes second primary cancers or death from any cause).
- PFS (Progression-Free Survival): Usually used in metastatic disease—time until disease worsens (progression) or death.
- EFS (Event-Free Survival): Includes relapse, progression, second cancer, or death as events.
Example: In an adjuvant melanoma trial, Talimogene laherparepvec (T-VEC) might not primarily measure OS but instead look at RFS as a key endpoint.