HEREDITARY CANCER SYNDROMES AND GENETIC RISK ๐ŸŽ—

“Hereditary cancer is not rare, but the diagnosis of hereditary cancer is.” -Dr. Henry T. Lynch

๐Ÿงฌ Hereditary cancer syndromes are genetic conditions that increase susceptibility to particular cancers. Unlike most cancers, which largely result from acquired genetic alterations, hereditary cancer predisposition can result from a pathogenic germline variant inherited from a parent. These variants may affect DNA repair, cell-cycle regulation, or tumour-suppressor pathways. Important examples include hereditary breast & ovarian cancer syndrome, commonly associated with BRCA1/BRCA2, and Lynch syndrome, associated with pathogenic variants in DNA mismatch-repair genes.

๐Ÿ”น Genetic risk refers to an increased probability of disease associated with inherited genetic factors. A pathogenic variant does not mean that cancer is inevitable; risk varies according to the gene, variant, sex, age, family history, & other genetic and environmental factors. Some syndromes also predispose individuals to multiple cancer types.

๐Ÿ”น Family history can provide important clues to hereditary cancer risk. Multiple relatives with related cancers, unusually early diagnoses, multiple primary cancers, or cancers occurring across generations may indicate an inherited predisposition. However, an apparently negative family history does not exclude hereditary risk because families may be small, medical histories incomplete, or pathogenic variants previously unrecognised.

๐Ÿ”น Genetic testing can identify pathogenic variants associated with hereditary cancer syndromes. Depending on the clinical context, testing may involve a single gene or a multigene panel. Genetic counselling is essential for explaining potential benefits, limitations, implications, & the interpretation of positive, negative, or uncertain results.

➡ Identifying hereditary cancer risk can support personalised prevention & early-detection strategies. Depending on the syndrome and individual risk, management may include earlier or more frequent surveillance, preventive medication, or risk-reducing surgery. Because inherited variants can be shared within families, cascade testing can also help identify relatives who may benefit from personalised risk assessment & management.

⚠ In an Oystershell, hereditary cancer syndromes delineates the important relationship between genetics & cancer susceptibility. Recognising inherited risk supports us to move beyond a population-based approach towards more personalised assessment, counselling, surveillance, & prevention. Importantly, genetic risk represents susceptibility, not certainty.

Abubakar Abubakar ✍

• Cohen SA, Pritchard, et al. Annual Review of Genomics & Human Genetics. 2019. PubMed

• Rebbeck TR, et al. Journal of the National Cancer Institute. 2007.

#HereditaryCancer #CancerGenetics #GeneticCounselling #GeneticTesting #PrecisionMedicine #BRCA1 #BRCA2 #LynchSyndrome #CRISPR #NGS #PGT #IVF #ART ⚕

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