ESMO Asia Congress 2022

Abstract 111P

Background

Biliary tract cancer (BTC) is an aggressive malignancy with a dismal prognosis. Although BTC has been explored more closely in the recent years, there are still no data on patients with early onset biliary tract cancer (EOBTC).

Methods

In this bicentric, real-world retrospective case-series, we studied the clinical data and molecular characteristics of therapy-refractory patients diagnosed with metastatic EOBTC who were below 50 years old at the age of initial diagnosis. The patients were treated between the years 2015 to 2021 at the two tertiary centers Medical University of Vienna and the University Hospital St. Poelten. Molecular profiling included next-generation sequencing panel, immunohistochemistry, tumor mutational burden (TMB) analysis, and microsatellite instability (MSI) testing.

Results

Overall, we analyzed 60 BTC patients who underwent molecular profiling, of whom 10 had an EOBTC, including 4 male and 6 female patients. Intrahepatic (n=7) subtype was most common, followed by extrahepatic (n=3). Eight patients were smokers. Primary sclerosing cholangitis and inflammatory bowel disease were reported in one and three patients, respectively. In most cases (n=48; 80%), patients had received a platinum-based therapy in first line. In total, we detected 22 genetic aberrations in 48 patients most commonly in KRAS (n = 15) and TP53 (n = 11). MSI-high and TMB-high status were both detected in one female patient. No genetic aberrations were found in 2 patients. At the time of molecular profiling, 2 patients had actionable mutations. Eventually, the female patient with MSI-high and TMB-high status received the targeted therapy, namely pembrolizumab. She achieved a complete response.

Conclusions

Based on our analysis, molecular profiling is feasible in tertiary centers for patients with metastatic EOBTC and may provide molecular-guided treatment approaches in this specific patient group.