Diagnosis and treatment strategies for hereditary pancreatic cancer syndrome.

Up to 10% of patients with pancreatic cancer (PC) harbor a germline pathogenic variant (GPV) of the hereditary cancer-associated genes that lead to hereditary pancreatic cancer (HPC). These include BRCA1/2, which is responsible for hereditary breast and ovarian cancer (HBOC); mismatch repair genes (Lynch syndrome); STK11 (Peutz-Jeghers syndrome: PJS); PRSS1 (hereditary pancreatitis); and CDKN2A/p16 (familial atypical multiple mole melanoma: FAMMM). The majority of GPVs seen in PC patients are clinically actionable and associated with the dysfunction of homologous recombination (HR) (BRCA1/2 in approximately 5%) and mismatch repair (approximately 1%). In the era of cancer precision medicine (CPM), GPV can be detected via routine oncological practices, so clinicians must be literate in both oncology and genetic medicine. Today's clinical guidelines recommend/propose genetic testing for PC patients and the surveillance of the at-risk individual's pancreas and other associated organs. Pancreatic surveillance is recommended to be performed with endoscopic ultrasound and magnetic resonance cholangiopancreatography. This is also compatible with abdominal US and enhanced computed tomography, coupled with serum tests of pancreatic enzymes and tumor markers, at intervals of once every 6-12 months. A GPV of BRCA suggests the effectiveness of platinum agents and PARP inhibitors against PCs. The need for genetic counseling and testing is increasing to support at-risk individuals in making autonomous decisions based on sufficient information. As PC ranks as the second-most common target of CPM in Japan, we must treat these patients and manage at-risk individuals efficiently.