Seonjeong Woo, Beodeul Kang, Sung Hwan Lee, Jung Sun Kim, Haeyoun Kang, Seok Jeong Yang, Chansik An, Gwangil Kim, Gae Hoon Jo, Chang‐Il Kwon, Min Je Sung, Suk Pyo Shin, Sanghoon Jung, Sohyun Hwang, Chan Kim, Hong Jae Chon
BACKGROUND AND AIMS: Nab-paclitaxel plus gemcitabine-cisplatin (Gem/Cis/nab-P) had promising efficacy in phase II trials for advanced biliary tract cancer (BTC) but failed to demonstrate superiority in phase III. We investigated Gem/Cis/nab-P efficacy and identified molecular subgroups with clinical benefit. APPROACH AND RESULTS: This prospective observational cohort study (NCT04871321) enrolled 119 patients with advanced BTC who received Gem/Cis/nab-P from July 2021 to December 2022. Of these, 108 were included in genomic and transcriptomic analyses of pretreatment tumor samples that met quality control criteria. Among 119 patients, 39.5% had intrahepatic cholangiocarcinoma, 37.0% extrahepatic cholangiocarcinoma, and 23.5% gallbladder cancer. Most patients had metastatic disease (68.9%). At a median follow-up of 23.7 months, the median progression-free survival was 8.3 months, and the median overall survival was 19.8 months. Grade ≥3 treatment-related adverse events occurred in 70 patients (58.8%), and dose reduction was required in 99.2%. Frequent genetic alterations were TP53 (53.7%), KRAS (29.6%), and CDKN2A (20.4%), with TP53 mutations being significantly associated with worse outcomes. Transcriptomic analysis identified 4 molecular subtypes: cholangiocyte-like, stromal, metabolic, and inflammatory-proliferative. The cholangiocyte-like subtype, marked by increased cholangiocyte markers, had the most favorable prognosis. Stromal and metabolic subtypes showed moderate outcomes, characterized by a fibroblast-rich stroma with activated angiogenesis and enriched metabolic pathways, respectively. The inflammatory-proliferative subtype had the worst prognosis, with cell cycle and inflammatory activation, and an exhausted immune microenvironment. CONCLUSIONS: This study demonstrated the clinical activity of Gem/Cis/nab-P in advanced BTC and highlighted that biology-driven patient stratification based on genomic and transcriptomic features may provide important prognostic information.