The absolute cause is unknown but it is more common in women who have a close relative (mother, sister, daughter) with the disease, in women who have not had a pregnancy, have not breast fed, have had a first pregnancy after 35 years, in white women, those who have had uterine cancer, and in higher socio-economic groups. On the other hand, women who start their periods late and those who have an early menopause have a lower incidence of breast cancer. About 2% of all breast cancers occur in men as they have a tiny amount of breast tissue present just under the nipple.
Extraordinarily, left-handed women have double the risk of developing breast cancer compared to those who are right handed.
The symptoms are a hard, fixed, tender lump in the breast which is not an infection caused by a skin cut or scratch. The nipple skin itself can become cancerous (Paget’s disease of the nipple) causing a thick, firm, rubbery feeling to the nipple. There are many other causes of lumps in the breast and less than one in ten breast lumps examined by a doctor is cancerous.