From figure 15 the single most striking observation is that the curve seems to be falling toward a limiting survival probability (horizontal asymptote).
However, that limiting probability is somewhat below 0.52 rather than anywhere near zero. The last focal event occurred after 20.7146 years, yielding an estimated survival probability of 0.5172. After that the curve appears to flatten out (i.e., to become virtually horizontal).
The bottom entry in the Kaplan-Meier survival table indicates that 173 other patients were followed up for more than 20 years to a maximum of about 28 years. None of them had yet experienced the focal event when last seen. Because the data suggested the existence of a limiting survival probability (horizontal asymptote), and because …show more content…
Exactly what proportion is not yet clear. The estimate of 0.52 based only on the flattening of the Kaplan-Meier survival curve provides an upper bound. One or more of the 153 survivors among alive censored patients could conceivably still have experienced the focal event, even after a decade or two.
A detailed analysis of the eventual outcomes of the 578 patients in the Guys
Hospital intervention sample yielded the following results.
suffered prior relapse/recurrence and died of breast cancer 235 suffered prior relapse/recurrence but died of something else 16 suffered relapse/recurrence but still alive when last seen 6 suffered no prior relapse/recurrence but died of breast cancer 2 ___
total number of patients who experienced the focal event 259
experienced no relapse/recurrence and died of something else 166 experienced no relapse/recurrence and still alive when last seen 153 ___
total number of censored patients (no focal event when last seen)
However, that limiting probability is somewhat below 0.52 rather than anywhere near zero. The last focal event occurred after 20.7146 years, yielding an estimated survival probability of 0.5172. After that the curve appears to flatten out (i.e., to become virtually horizontal).
The bottom entry in the Kaplan-Meier survival table indicates that 173 other patients were followed up for more than 20 years to a maximum of about 28 years. None of them had yet experienced the focal event when last seen. Because the data suggested the existence of a limiting survival probability (horizontal asymptote), and because …show more content…
Exactly what proportion is not yet clear. The estimate of 0.52 based only on the flattening of the Kaplan-Meier survival curve provides an upper bound. One or more of the 153 survivors among alive censored patients could conceivably still have experienced the focal event, even after a decade or two.
A detailed analysis of the eventual outcomes of the 578 patients in the Guys
Hospital intervention sample yielded the following results.
suffered prior relapse/recurrence and died of breast cancer 235 suffered prior relapse/recurrence but died of something else 16 suffered relapse/recurrence but still alive when last seen 6 suffered no prior relapse/recurrence but died of breast cancer 2 ___
total number of patients who experienced the focal event 259
experienced no relapse/recurrence and died of something else 166 experienced no relapse/recurrence and still alive when last seen 153 ___
total number of censored patients (no focal event when last seen)