Conditional survival in patients with unresectable perihilar cholangiocarcinoma

Background
Conditional survival is the life expectancy from a point in time for a patient who has survived a specific period after presentation. The aim of the study was to estimate conditional survival for patients with unresectable perihilar cholangiocarcinoma.

Methods
Patients with unresectable perihilar cholangiocarcinoma from two academic hospitals in the Netherlands between 2002 and 2012 were assessed. A multivariable Cox proportional hazards analysis was performed to identify risk factors associated with overall survival. Survival was estimated using the Kaplan–Meier method to evaluate factors associated with overall survival.

Results
In total, 572 patients were included. Overall survival was 42% at one year and 6% at three years. The conditional chance of surviving three years was 15% at 1 year and increased to 38% at 2 years. Independent poor prognostic factors for overall survival were age ≥65 years, tumor size >3 cm on imaging, bilirubin levels (>250 μmol/L), CA19-9 level at presentation (>1000 U/ml), and suspected distant metastases on imaging. The conditional survival of patients with and without these prognostic factors was comparable after patients survived the first two or more years.

Conclusion
The conditional chance of surviving for patients with unresectable perihilar cholangiocarcinoma increases with time. Poor prognostic factors become less relevant once patients have survived two years.