Conditional Survival Analysis of Metastatic Colorectal Cancer Patients Living ≥24 Months

Abstract

Objectives-The survival of patients with metastatic colorectal cancer (CRC) has been increasing over recent decades due to improvements in chemotherapy and surgery. There is a need to refine prognostic information to more accurately predict survival as patients survive for any given length of time to assist multidisciplinary cancer management teams in treatment decisions. Methods-We performed a single center retrospective analysis of patients treated with metastatic CRC (unresectable and resectable) who survived >24 months between 2005 and 2015 (N = 155). Patient tumor and treatment related variables were collected. Overall survival (OS) estimates conditional on surviving >24 months were compared with actuarial survival estimates of a cohort of patients (33,104 resected, 39,382 unresected) from the National Cancer Database (NCDB). Results-With a median follow up of 44.2 months, the median OS of resected patients (n=86) was not reached. The median OS of unresected patients was 75.9 months. The conditional survival probabilities of living 1, 2 or 3 years longer after 24 months of survival are 92%, 72% and 52% respectively in unresectable patients and 98%, 92% and 89% in patients who were resected. The corresponding NCDB 1,2 and 3 year actuarial survival was 38%, 20%, and 11% for unresected patients and 68%, 46%, and 32% for resected. *

A novel prognostic time window based on conditional survival and outcomes analyses of primary liver cancer patients

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Individualized prediction of conditional survival for colorectal signet ring cell carcinoma patients

“…Conditional survival (CS) represents the probability of surviving for additional years after already surviving for certain years. CS assessments provide important quantitative information about the probability of survival over time and should be regarded as a more precise tool for prognosis analysis 10 – 12 .…”