Clinical utility of comprehensive genomic profiling in patients with unresectable primary liver cancer.

Abstract

542 Background: Comprehensive genomic profiling (CGP) using tissue and blood specimens is covered by national health insurance for patients who have already received standard systemic therapy in Japan. We investigated the clinical utility of CGP in patients with unresectable primary liver cancer in real-world practice. Methods: We retrospectively investigated the clinical outcome of the patients with unresectable primary liver cancer. All patients received CGP between February 2021 and May 2022 at our institution. Results: 17 patients with unresectable primary liver cancer were included. 10 patients had hepatocellular carcinoma (HCC) and seven had intrahepatic cholangiocarcinoma (ICC). In HCC patients, the treatment line at CGP was 4th (n=5), 5th (n=4), and 6th-line (n=1). The samples were from liver tumor biopsy (n=2), surgical specimens of bone metastases (n=2), and blood (n=6). Clinically meaningful oncogene mutations were detected in all HCC cases. Seven of 10 patients were candidates for clinical trials, and 1 patient showed TMB-high. Six of the 7 patients could not participate in clinical trials due to renal dysfunction, low platelet counts, the immune-related adverse event of past therapy, or HBV infection. One patient with TMB high started pembrolizumab. In ICC patients, the treatment line at CGP was 1st (n=6), and 2nd -line (n=1). The samples were from liver tumor biopsy (n=5), blood (n=1) and surgical specimens of lung metastases (n=1). Clinically meaningful oncogene mutations were detected in all ICC cases. Six of 7 patients were candidates for clinical trials, and 1 patient showed MSI-high. One patient with MSI high started pembrolizumab, and one patient with FGFR2 fusion could use pemigatinib as 3rd line. The Overall survival duration of this patient with ICC (StageⅣB) was 26 months. In total, 13 of 17 patients were candidates for clinical trials, and 4 of 17 patients could receive personalized therapy according to the results of CGP. Conclusions: CGP in patients with unresectable primary liver cancer was useful in real-world practice. However, most patients could not participate in clinical trials because of adverse events associated with previous therapies. The best timing of CGP should be discussed in the future to provide more personalized therapies.