Transplantation Within 6 Months of Registration Does not Enhance Survival for Patients With Perihilar Cholangiocarcinoma

Objectives: – Determine whether the timing of transplantation affects patient mortality. Background: – Neoadjuvant therapy and liver transplantation have emerged as an excellent treatment option for select patients with perihilar cholangiocarcinoma (pCCA). However, the optimal timing of transplantation is not known. Methods: – We reviewed all patients registered for a standardized pCCA protocol between 1996 and 2020 at our center. After adjusting for confounders, we examined the association of waiting time with patient mortality in an intention-to-treat cohort (n=392) and those who received a liver transplant (n=256). Results: – The median (interquartile range) time from registration to transplant or dropout was 5.74 (3.25–7.06) months. Compared with a short wait time (0–3 mo), longer waiting times did not affect all-cause mortality: (3–6 mo) hazard ratio (HR) 0.98; 95% CI: 0.52–1.84; (6–9 mo) HR: 0.80; 95% CI: 0.39–1.65; (9–12 mo) HR: 0.56; 95% CI: 0.26–1.22. Subgroups with a shorter waiting time had similar survival to those with long waiting times: living donor available HR: 0.97; 95% CI: 0.67–1.42; AB or B blood group HR: 0.93; 95% CI: 0.62–1.39. Longer waiting times were associated with decreased all-cause mortality after transplantation (HR: 0.92; 95% CI: 0.87–0.97). This benefit began after a 6-month waiting time minimum (HR: 0.53; 95% CI: 0.26–1.10) and increased further after 9 months (HR: 0.43 95% CI: 0.20–0.93). Waiting time was not associated with residual adenocarcinoma in the explant (odds ratio 0.99; 95% CI: 0.98–1.00). Conclusions: – A waiting time of at least 6 months will optimize results with transplantation without affecting overall (intention-to-treat) patient survival.