Radiation Oncology/Survival curve terminology

Definitions of terminology used in reporting cancer survival statistics. (NOTE: different authors may use varying definitions. Examples of trials using certain definitions are given for the purpose of comparison.)

Survival statistics

 * Overall survival (OS)
 * From date of diagnosis until death from any cause.
 * Disease-free survival (DFS)
 * From date of diagnosis until date of first recurrence, locoregional or systemic. All other events were censored.
 * Events are death or recurrence.
 * May also include second primary tumors (NSABP B-04).
 * Only includes pts who reached a CR at the end of treatment.
 * Local-recurrence-free survival
 * Locoregional recurrence-free survival
 * 1) survival free of an isolated locoregional recurrence at a minimum of 6 months before a systemic event, or 2) survival free of locoregional recurrence occurring at any time before systemic recurrence. Other events were censored.
 * Event-free survival
 * From date of diagnosis until 1) locoregional or systemic recurrence, 2) second malignancy, or 3) death from any cause
 * 1) disease progression or relapse, institution of new unplanned anticancer treatment, or death from any cause


 * Disease-specific survival
 * From diagnosis until death due to the cancer (with or without a prior known date of locoregional or systemic relapse). All other causes of death censored.
 * Metastasis-free survival
 * Relapse-free survival (RFS)
 * Includes any recurrence. Does not include death (i.e., deaths are censored). May also include a contralateral breast cancer that is deemed a recurrence of the primary tumor (NSABP B-04).
 * Progression-free survival (PFS)
 * Same as EFS except late deaths not related to cancer or its treatment were excluded. 1) disease progression or relapse, institution of new unplanned anticancer treatment, or death related to disease


 * Systemic disease-free survival
 * From date of diagnosis until date of first systemic recurrence, including: 1) systemic recurrence outside the locoregional area at any time before or after locoregional relapse, 2) systemic recurrence with or without locoregional relapse, or 3) death from cancer with no information on systemic recurrence. (All other causes of death were censored.)


 * Freedom from progression (FFP)
 * Until first treatment failure. Includes failure to achieve CR (as opposed to RFS). Does not include deaths.

Tumor response

 * CR - complete response
 * CRu - complete response (undocumented)
 * PR - partial response
 * Stable disease
 * Progressive disease