Women who obtain a benign breast disease diagnosis through screening have a nearly doubled chance of acquiring breast cancer, according to studies presented at the 13th European Breast Cancer Conference. The study compared women who had any benign breast illness, including fibroadenomas and cysts, against those who had not been diagnosed with a breast disease. It included about 7,000,000 Spanish women who had their breasts screened. Researchers believe that this group of women might benefit from more frequent screening to ensure that cancer is detected early, when the odds of survival are greatest. Breast cancer risk remained higher for at least two decades.
The study was presented at the conference by Dr Marta Roman of the Hospital del Mar in Barcelona, Spain, and it was also published in the International Journal of Environmental Research and Public Health. It included 778,306 women between the ages of 50 and 69 who had at least one breast screening at one of 20 centres in Spain between 1996 and 2015. Every two years, all women in this age range in Spain have mammography for breast cancer screening. Researchers followed the women up until 2017, when 17,827 of them were diagnosed with benign breast disease and 11,708 with breast cancer.
According to the data, around 25 out of every 1,000 women with benign breast sickness went on to be diagnosed with breast cancer. Breast cancer was diagnosed in about 15 out of every 1,000 women who did not have benign breast disease. Women with benign breast illness were shown to be at greater risk regardless of age, and the risk lasted for at least 20 years. Breast cancer diagnoses were 99 percent more frequent among women who had been observed for less than four years than in those who had been followed for 12 to 20 years.
“This is important,” Dr Roman explained. “It suggests that benign breast disease is a key indicator that a woman has a higher risk of breast cancer, rather than simply being something that could develop into cancer. In fact, we often find a benign disease in one breast and then cancer develops in the other breast.
“We can use this knowledge, alongside what we know about other risk factors, to help optimise the breast screening that we offer to women. For example, if a woman is diagnosed with a benign breast disease, and she has other high-risk factors, such as a family history of breast cancer, she could benefit from more frequent screening.”
Professor David Cameron of the University of Edinburgh Cancer Research Centre, UK, represents the European Breast Cancer Council at EBCC13 and was not involved in the research.
He said: “Screening can help diagnose breast cancer at an earlier stage when the chances of survival are greater. This large study shows that women in a screening programme who are diagnosed with a benign breast disease appear to be at a higher risk of being diagnosed with breast cancer in the long term and they may therefore benefit from enhanced screening.
“Mammograms quite often pick up signs of breast disease that are not cancer, such as cysts and fibroadenomas, and it’s important to remember that the majority of women with these conditions will not go on to develop breast cancer.”