The link between a woman’s reproductive life and the risk of breast cancer, the most frequent neoplasia in women in Italy, is very close. In fact, the probability of breast cancer onset increases in combination with several factors: not only premature menarche, i.e. the first menstruation, but also late entry into menopause. “Menarche and menopause are the two elements that inaugurate and finish the reproductive story of women. The extension of this fertile period can have repercussions on the risk of breast cancer,” recalls Dr. Andrea Sagona, breast surgeon at the Humanitas Cancer Center.
More diagnoses, fewer deaths
For 2017, the Italian Association of Medical Oncology estimated more than fifty thousand breast cancer diagnoses, a cancer that also causes more deaths among women. However, the trend has slightly increased in incidence in recent years, but is decreasing in mortality rates. This form of neoplasia remains firmly in first place among the most common cancers that affect women. This remains true in all three age groups: up to forty-nine years of age, from fifty to sixty-nine years and above seventy years of age.
If we look at the incidence by age group, we can see how this increases up to the menopause years, then in the 50-55 age group, and then it slows down before beginning to increase again after the age of sixty. This trend is suggestive of the relationship between the length of the fertile period and the risk of cancer disease. Early menarche and late menopause are two risk factors associated with the reproductive life of a woman, together with, for example, the age of the first term pregnancy after age of 30 or nulliparity (the fact that she had no children).
Hormones and breast cancer
As has already been widely reported by scientific research, in the period between the increase in risk and the duration of a woman’s fertile period there is exposure to steroid hormones produced by the ovaries that directly affect the development and function of the breast. Thus, the breast tissues are continuously and progressively stimulated by the action of these hormones.
A study published in Lancet Oncology – a substantial review of more than one hundred epidemiological studies with data referring to just under 119,000 women with breast cancer – related the risk of breast cancer to late menopause and early menopause. “It has been shown how cancer risk increased significantly in the case of early menarche and each extra year in one fertile period,” recalls Dr. Sagona.
It should be noted that the increased risk of developing breast cancer was higher for early menarche than for late menopause, probably due to excessive stimulation of the mammary gland at a critical stage of its development.
Women are able to reduce the probability of breast cancer onset for as long as possible by controlling modifiable risk factors and actively preventing them also by participating in screening programmes: “Typically every two years, women over the age of 50, and up to sixty-nine, may in fact undergo mammography according to the provisions of national screening. This period of time has been extended to include women aged 45 to 74, given the increase in cases even at a younger age and the risk still present after 69 years of age. Early diagnosis is important in order to make the course of a possible pathology more favorable”.
“Every woman, starting from adolescence, should lead a healthy and active lifestyle by trying to control body weight, avoid being overweight as well as obesity, maintaining a healthy and balanced diet, avoid the habit of cigarette smoking, avoid or limit the consumption of alcoholic beverages as much as possible (especially in adolescence, where alcohol damage on breast tissue is greater), try to maintain aerobic physical activity”, concludes Dr. Sagona