Mammary Gland Diseases: Carcicoma

Cáncer de mama

Breast carcinoma is the most common cancer in women in the United States, and since 1940 the age-adjusted incidence has increased; It is currently diagnosed in one in nine Americans during their lifetime. The death rate from breast cancer is second only to lung cancer.

Its cause is likely to be multifactorial. Female sex is a predisposing factor, since only one male shows breast carcinoma for every 100 women diagnosed.

The incidence increases with age. It begins after age 20 and reaches a stable level (plateau) around menopause, then increases net after that change. Genetic factors are important in 15% of cases, and are most noticeable in women whose mother had carcinoma in both breasts before menopause. England and Wales have the highest national breast cancer mortality and Japan the lowest.

The highest risk is related to nulliparity and the first pregnancy in the last years of fertility. Estrogens induce breast cancer in mice, but no theory of induction by hormones or birth control pills has been substantiated in humans.

Among the risk factors that have been proposed are obesity, abundant consumption of animal fats and viral factors transmitted by breast milk.

The natural course of the disease has been cited in studies since the end of the last century, at Middlesex Hospital, London, in which the median survival in 250 untreated women was 2.7 years; Survival was calculated based on the description of the onset of the first symptoms.

The five-year survival was 18% and the decennial 3.76%. Necropsies showed that 95% of women died of breast carcinoma and of them 75% had breast ulcers. Biological features of breast cancer: typical scirrhosal adenocarcinoma begins in the superoexternal quadrant (45%) of the left breast (60%) and it takes 30 duplications from the single-cell stage, for a period of five to eight years to reach a palpable size (1 cm in diameter).

Metastases arise when the tumor is 0.5 cm in diameter and the prognosis is adversely influenced by the number of axillary lymph nodes affected. With the aforementioned enlargement fibrosis shortens the Cooper's ligament and there is the characteristic depression or dimpling of the skin.

Systemic spread is most common to lungs (65%), bone (56%), and liver (56%).

The diagnostic investigation should be done in an orderly manner. In any suspicious lesion, aspiration biopsy should be performed and then by partial (incisional) removal, in the direction of the skin folds (periareolar), or as a convenient resource in case of possible segmental resection or subsequent mastectomy. Staging can be done before definitive treatment and includes a chest x-ray and liver function tests. Skeletal x-rays and bone scans are not required when there are no specific symptoms.