Thus, combination therapy with paclitaxel and platinum drugs or oral treatment with PARP inhibitors, which are effective in patients with platinum-sensitive HBOC or HRD-positive ovarian cancer, can be utilized in patients with GC harboring germline BRCA1/2 mutations with PVs and/or HRDTo validate the efficacy of olaparib, patients with advanced-stage/metastatic GC in whom PVs were detected in any of the 10 homologous recombination genes (ATM, BARD1, BRCA1, BRCA2, BRIP1, CDK12, CHEK2, PALB2, RAD51C, and RAD51D) were randomized to receive either olaparib plus paclitaxel or paclitaxel alone. Here, CHEK2 is linked to gastric cancer.