Between five and 10 per cent of pancreatic cancers arise due to a genetic predisposition. A referral to a familial cancer service should be considered for all patients newly diagnosed with pancreatic cancer, particularly if any of the following features are noted:

• a family history of pancreatic cancer
• young age of diagnosis (< 60 years)
• a personal and/or family history of melanoma, breast, ovarian, stomach or colorectal cancer
• a family history of chronic pancreatitis
• Ashkenazi Jewish ancestry.

Genetic testing is sometimes able to identify the cause of pancreatic cancer in an affected individual and, if relevant, their family. An assessment at a familial cancer service can determine if genetic testing is appropriate. Genetic testing can involve testing a single gene or multiple genes at the same time. Where possible, genetic testing will begin in a person affected by pancreatic cancer to identify a predisposing heritable gene mutation. Identifying a gene mutation could improve access to targeted treatment (such as the use of PARP inhibitor therapy in a BRCA gene mutation carrier with advanced pancreatic cancer) and ensure that any other associated cancer risk can also be managed. If a gene mutation is identified, predictive testing will also be available to relatives to see if they have inherited the gene mutation or not. Genetic counselling and fully informed consent is required before proceeding with genetic testing.

If an affected individual or family does not meet the criteria for funded genetic testing, the option of self-funded genetic testing may be discussed. Self-funded genetic testing is increasingly becoming an option as the cost of genetic testing continues to reduce and due to the potential therapeutic implications if a relevant gene mutation is identified.

If an affected individual is unsure or unable to proceed with genetic counselling and/or testing, the option of DNA storage should be discussed as soon as possible. DNA storage may allow their family members to access genetic testing in the future even if the affected individual is unable to or chooses not to proceed with genetic testing.

Visit the Centre for Genetics Education website for basic information about cancer in a family.