Current status of cancer genome medicine for pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis; however, advancements in cancer genome profiling using next-generation sequencing have provided new perspectives. KRAS mutations are the most frequently observed genomic alterations in patients with PDAC. However, until recently, it was not considered a viable therapeutic target. Although KRAS G12C mutations for which targeted therapies are already available are infrequent in PDAC, treatments targeting KRAS G12D and pan-KRAS are still under development. Similarly, new treatment methods for KRAS, such as chimeric antigen receptor T-cell therapy, have been developed. Several other potential therapeutic targets have been identified for KRAS wild-type PDAC. For instance, immune checkpoint inhibitors have demonstrated efficacy in PDAC treatment with microsatellite instability-high/deficient mismatch repair and tumor mutation burden-high profiles. However, for other PDAC cases with low immunogenicity, combination therapies that enhance the effectiveness of immune checkpoint inhibitors are being considered. Additionally, homologous recombination repair deficiencies, including BRCA1/2 mutations, are prevalent in PDAC and serve as important biomarkers for therapies involving poly (adenosine diphosphate-ribose) polymerase inhibitors and platinum-based therapies. Currently, olaparib is available for maintenance therapy of BRCA1/2 mutation-positive PDAC. Further therapeutic developments are ongoing for genetic abnormalities involving BRAF V600E and the fusion genes RET, NTRK, NRG, ALK, FGFR2, and ROS1. Overcoming advanced PDAC remains a formidable challenge; however, this review outlines the latest therapeutic strategies that are expected to lead to significant advancements.