CHEK2 and breast cancer: For instance, we mention a phase II clinical trial on olaparib in patients with cancers underlying germline or sporadic pathogenic variants with homolog recombination that revealed encouraging results for BRCA1 (breast cancer gene) and BRCA2 genes and not for other genes such as ATM (Ataxia-telangiectasia mutated) or CHEK2 (checkpoint kinase) with partial results for pancreas neoplasia and parathyroid carcinomas [197].