Heredity is not primarily the cause of tumors, despite representing a risk factor in several types of cancer, such as breast and prostate. The genetic alterations that give rise to the disordered proliferation of malignant cells in the body can be triggered by tobacco use, alcohol intake, sedentary lifestyle or poor diet, for example.
No. Family history is just one risk factor for developing the disease: having a cancer predisposing gene does not determine its occurrence.
Genetic tests can help both in the prevention and treatment of cancer. By looking for inherited changes in the individual’s genes, the doctor can assess the risk of developing the disease. When the person already has cancer, the tests can identify exactly which types of cells are affected; thus facilitating the application of a more precise therapy, such as the use of molecular-targeted drugs.