Introduction
Biliary tract cancers (BTC), encompassing intrahepatic and extrahepatic cholangiocarcinoma as well as gallbladder cancer, represent a heterogeneous group of malignancies with poor prognosis due to late-stage diagnosis and aggressive tumor biology. Systemic chemotherapy remains the mainstay for unresectable or metastatic BTC. While gemcitabine plus cisplatin (GemCis) has been the standard first-line treatment, the addition of immunotherapy agents such as durvalumab or pembrolizumab has recently demonstrated survival benefits. Despite these advances, disease progression after first-line therapy is common, underscoring the need for effective subsequent treatments. Current guidelines favor FOLFOX as second-line therapy, particularly in patients without actionable mutations. However, alternative regimens remain an area of active investigation.
Liposomal irinotecan (nal-IRI) combined with fluorouracil and leucovorin (5-FU/LV) is approved in advanced pancreatic cancer after gemcitabine failure. Two phase 2 trials—the Korean NIFTY and German NALIRICC—evaluated nal-IRI plus 5-FU/LV in gemcitabine-pretreated BTC patients, yielding conflicting results. This incongruity prompted an individual patient-level pooled analysis to assess efficacy and safety comprehensively across ethnic populations.
