Seven out of ten tumors, which are found in the breast are usually benign. Benign tumors are distinguished from malignant tumors, including cancer, in that their cells do not usually have those properties that cancer. The growth of malignant cells is not like cancer, they do not grow in normal tissue, and do not form metastases. Often, a woman who learned the results of a biopsy that she had a benign tumor, it would be like "a stone falls to the soul." However, be aware that some benign breast tumors may increase risk of cancer.
Studies have shown that the risk in these women increased by 50 - 60%. It is not known whether all types of benign tumors leads to an increased risk of breast cancer or certain.
To find out what types of benign tumors are associated with an increased risk of developing breast cancer, researchers have for several years conducted surveillance of women who are removed are benign tumors of the mammary glands. Most of the women were observed for 15 years. In one study examined a large number of women with benign tumors.
The aim of the study was to determine what percentage of women who have or had at one time the formation of benign breast cancer, later suffered from breast cancer.
The researchers studied data on 9087 patients during the period from 1967 to 1991. Age of women was in the range 18 - 85 years. The researchers asked patients the following questions:
Have a family history of breast cancer.
Age and menstrual status at the time of surgery.
Was she ever breast cancer.
In addition, each woman held a survey carried out a biopsy of benign breast tumors. The results obtained biopsies of benign tumors were divided into three groups:
No proliferative changes - these are the fibrous tissue that make up the ligaments and tendons, or cysts.
Proliferative changes - with the growth and formation of new cells more quickly than normal. Atypia is not marked.
Proliferative changes - with the growth and formation of new cells more quickly than normal. It is also noted atypia. Atypia means that the cells differ in structure from normal, for example, the content of the nuclei. In atypical ductal hyperplasia, the abnormal cells are located in the ducts of the breast. In atypical lobular hyperplasia, abnormal cells are found in glandular tissue.
The results showed that the risk of developing breast cancer in benign tumors is increased by 56%. This increased risk was noted for 25 years after the removal of benign breast tumors. All benign tumors of the mammary glands were separated from women studied in three categories:
66.7% - non proliferative changes.
29.6% - proliferative changes without atypia cells.
3.7% - proliferative changes with atypia cells.
In addition, this study showed that the type of benign tumor diagnosed affect the ability of breast cancer in the future. On this basis, we obtained the following data: in patients with atypical hyperplasia, the risk of developing breast cancer was 424% (that is 4 times higher). In patients with proliferative changes without atypia cells the risk of developing breast cancer was 88%. In nonproliferative changes in the risk of developing breast cancer in the future, was 27%.
Familial predisposition to breast cancer also plays a role.
Women with "severe" family history (first degree relatives have had breast cancer before age 50 years) risk of developing breast cancer was 93%. For first-degree female relatives include his mother, sister or daughter. In women with a "weak" family history risk for breast cancer was 43%. In women without a family history risk for breast cancer was 18%. However, to learn about family history in the study was only half of the surveyed women.
The researchers also studied the average age of women with benign tumors: in women younger than 45 years with atypical hyperplasia, the risk of developing breast cancer was 7 times higher. In women under age 45 to 55 years, the risk of developing breast cancer was five times higher. In women older than 55 years with atypical hyperplasia, the risk of developing breast cancer was three times higher.
It is important to note that women with nonproliferative type of benign mammary tumors in the absence of family history risk for breast cancer was absent.
As a result, studies have concluded that certain types of benign tumors may increase the risk of breast cancer.
Further, it was found that:
Women with atypical hyperplasia, the risk of developing breast cancer was 42.4% (ie 4-fold) in the case of familial predisposition.
Women with proliferative changes without hyperplasia, the risk of developing breast cancer was 88%.
Among women with nonproliferative benign tumors the risk of developing breast cancer was 27%.
Women with atypical hyperplasia under the age of 45 years, the risk of developing breast cancer was much higher. They have this risk is 7 times higher.
Among women with nonproliferative tumors without familial predisposition to breast cancer risk for this disease was absent.
