The advanced biliary tract cancer (ABC)-02 study established cisplatin and gemcitabine (CisGem) as a reference 1(st)-line regimen for patients with advanced/metastatic biliary tract cancer; patients with bilirubin ⩾ 1.5 × upper limit of normal (ULN) were excluded and there are few extant data for systemic treatment in the context of elevated bilirubin.

Patients with ABC, receiving CisGem with a baseline bilirubin of ⩾ 1.5 × ULN were eligible for this retrospective analysis; response, toxicity and survival data were collected.

Thirty-three patients of 545 screened; median age 59 years, range 23-79; 58% male, 58% with metastases (79% in the liver) of performance status (PS) 0 (33%), 1 (64%) or 2 (3%) were eligible. The median baseline bilirubin was 55 μmol/L (range 32-286); due to biliary tract obstruction (BTO, 76%) or liver metastases (LM, 24%). Toxicity was comparable to the ABC-02 study; bilirubin normalised in 64% during chemotherapy/follow-up. The median progression-free survival (PFS) was 6.9 months (95% confidence interval (CI): 4.4-9.0) and median overall survival (OS) 9.5 months (95% CI: 5.7-12.8). Patients with BTO had a longer PFS and OS than those with LM (7.0 versus 2.6 months; p = 0.1633 and 9.8 versus 4.4 months, hazard ratio (HR) 0.74; p = 0.465, respectively); not statistically significant (due to small sample size). Normalisation of bilirubin and completion of eight CisGem cycles were associated with longer OS (11.4 versus 2.9 months, HR 0.49; p = 0.08 and 15.2 versus 5.4 months, HR 0.12 p < 0.001, respectively). No difference in OS was shown between the bilirubin percentiles (for either PFS or OS).

For PS 0-1 patients with ABC and high bilirubin due to luminal disease despite optimal stenting CisGem can be used safely with results similar to those in patients with normal bilirubin.