Introduction and epidemiologyBreast cancer is the most frequent neoplasia among women and represents 30% of all cancers. In Catalonia in 2002, the crude incidence rate was 116.5/100,000 women and the age-adjusted incidence rate in the world standard population was 70.9/100,000 women. Breast cancer is the main cause of cancer death in women. Mortality increased until 1991Mortality increased until -1992, and then decreased up to the present. The adjusted mortality rate rose from 17.8 cases/100,000 women in 1985 to 18.8 in 1995. It then dropped to 15.3 cases/100,000 women in 2002. There are several reasons for this change, including therapeutic advances and the introduction of measures for the early diagnosis of breast cancer. Five-year survival from breast cancer increased significantly to 75.9% in 1990-1994, then to 80.9% in 1995-1999 [3-5].The main risk factors for breast cancer are related to hormonal, reproductive, sex, age and family history factors. Between 15 and 20% of new cancer cases are estimated to occur in a family with a history of cancer and from 5 to 10% of cases could be related to the inheritance of a genetic predisposition to the disease. The discovery of cancer-related genes has enabled carriers of an inherited predisposition to cancer to be identifi ed, so that the risk can be defi ned and prevention behaviour encouraged. In addition, specifi c screening can be undertaken in order to make early diagnoses [6][7][8]. Guidelines for suspected cancerThe main aim is to obtain a pathological diagnosis of the lesion before therapy begins. Studies of patients with suspected cancer should include the following tests: clinical examination, imaging and biopsy. [S]Evidence shows that the combination of these three investigations (the triple test) leads to higher diagnostic accuracy [9] [II], [SIGN] [10].