Disease-free survival was defined as time on the study without 1) recurrence of breast cancer at local, regional, or distant sites; 2) occurrence of a second primary cancer; or 3) occurrence of death prior to those events. Ipsilateral breast tumor recurrences after lumpectomy were also considered to be local events.
Distant disease-free survival was defined as time on the study free of both tumor recurrence at distant sites and second primary cancers. Distant failures were included regardless of whether they occurred as first events or as events subsequent to local or regional failures. Deaths that occurred prior to distant treatment failures or to second primary cancers were censored. Events for the survival end point were deaths from any cause. Time-to-event …show more content…
Average annual rates of specific events comprising disease-free survival were computed and compared by use of exact binomial probabilities.
The Cox proportional hazards model was used to examine prognostic covariates and to test for interactions between treatment and the covariates (11). Age at diagnosis, clinical tumor size, ER status, and PgR status were evaluated for association with disease-free survival and survival. Outcomes with regard to …show more content…
Outcomes with regard to clinical tumor size were evaluated in categories according to tumor size, i.e., 2 cm or less and greater than 2 cm, and as a continuous variable. Outcome was also evaluated relative to tumor PgR content, i.e., negative (<10 fmol/mg cytosol protein) or positive (ù10 fmol/mg cytosol protein), and to tumor ER content, which was examined as a continuous variable and categorized according to the stratification categories used at randomization. Model results have been summarized as
Distant disease-free survival was defined as time on the study free of both tumor recurrence at distant sites and second primary cancers. Distant failures were included regardless of whether they occurred as first events or as events subsequent to local or regional failures. Deaths that occurred prior to distant treatment failures or to second primary cancers were censored. Events for the survival end point were deaths from any cause. Time-to-event …show more content…
Average annual rates of specific events comprising disease-free survival were computed and compared by use of exact binomial probabilities.
The Cox proportional hazards model was used to examine prognostic covariates and to test for interactions between treatment and the covariates (11). Age at diagnosis, clinical tumor size, ER status, and PgR status were evaluated for association with disease-free survival and survival. Outcomes with regard to …show more content…
Outcomes with regard to clinical tumor size were evaluated in categories according to tumor size, i.e., 2 cm or less and greater than 2 cm, and as a continuous variable. Outcome was also evaluated relative to tumor PgR content, i.e., negative (<10 fmol/mg cytosol protein) or positive (ù10 fmol/mg cytosol protein), and to tumor ER content, which was examined as a continuous variable and categorized according to the stratification categories used at randomization. Model results have been summarized as