Survival probability changes over time for cancer patients, and estimates of prognosis made at the time of diagnosis are no longer applicable after a patient has already survived for a period of time after diagnosis and treatment. Conditional survival (CS) is a more accurate estimate of prognosis for these cancer survivors because it accounts for the continuously changing hazard rates over time. CS estimates can be helpful for patients and providers who seek more accurate prognostic estimates to help guide health-related decisions. This information enables cancer survivors to more accurately assess whether their prognosis is improving or declining over time. It can also be used by providers to determine appropriate follow-up and surveillance testing.
This prediction calculator will make an individualized estimate of the conditional survival for a rectal cancer survivor, after a certain period of time has passed since diagnosis and treatment.
Enter the patient details below and the number of months since diagnosis to calculate the patient's conditional survival, i.e., the likelihood of surviving additional years given that he or she has already survived a period of time.
Conditional survival prediction is calculated from a Cox proportional hazards model built from a series of rectal cancer patients from the SEER 17 database who were diagnosed between 1994-2003. For more information, see Wang SJ, Wissel AR, Luh JY, Fuller CD, Kalpathy-Cramer J, Thomas CR. An Interactive Tool for Individualized Estimation of Conditional Survival in Rectal Cancer. Ann Surg Oncol, 2011; 18(6):1547-1552.