Cancer can result from several factors, a combination of both environmental and genetic. Although most tumours are sporadic and multifactorial, there are certain genetic abnormalities inherited from one or both parents which are present in almost all cells of the body, including sperm and eggs, which can therefore be passed on in a family.
 
Hereditary cancers are the result of germline mutations in specific genes which increase the chance of developing cancer.
 
Although being a carrier of a genetic mutation does not always imply that a person will develop cancer, it does make them more susceptible, these higher risk factors mean they must be monitored more closely.

The most common Cancer Predisposition Syndromes are:
 

• Hereditary Breast and Ovarian Cancer Syndrome (HBOS), , due to the genes (BRCA1, BRCA2, PALB2, RAD51) which usually lead to breast, prostate, or pancreatic cancer.

 

• Lynch syndrome , (MLH1, MSH2, MSH6, PMS2) ) which lead to tumours including colorectal or ovarian tumours, and those of the urinary tract, stomach, and small intestine.

 

• Familial Adenomatous Polyposis, , (FAP) causing colorectal, duodenal, desmoid, stomach and pancreatic cancer and osteomas.

 

• Li- Fraumeni Syndrome, (TP53)which causes leukaemia, lymphoma, sarcoma, brain and breast tumours.

 

• Multiple Endocrine Neoplasia Type 1, , (MEN1) the origin of parathyroid adenomas, pituitary adenomas, neuroendocrine tumours.

 

• Multiple Endocrine Neoplasia Type 2, (MEN2) which causes medullary thyroid cancer, pheochromocytoma, and parathyroid adenomas.

 

• Von Hippel-Lindau , (VHL) que originan cáncer de riñón, hemangioblastomas, feocromocitomas.

• The probability of developing cancer

 

• The probability of passing on a mutation to children.

 

This information enables specialist doctors to determine early prevention strategies or preventative therapeutic measures when someone is faced with the possibility of developing cancer.
 
Depending on the circumstances, the following may be recommended:
 

• Periodic active surveillance by a medical specialist

 

• Chemoprevention

 

• Prophylactic surgery

BRCA I AND BCRA II: Genetic test to determine the risk of hereditary breast and ovarian cancer, facilitating monitoring and preventative action.
 
Determination of Microsatellite Instability (MSI) and Alterations in DNA Repair Proteins. Tests to determine the risk of hereditary colorectal cancer and familial syndromes such as Lynch syndrome. This instability determination also provides the sensitivity of tumours to treatment with immunotherapy.