Mammograms for the early detection of breast cancer should begin at age 40, be repeated every two years, and continue until age 74, according to new recommendations approved by the United States Preventive Services Task Force (USPSTF). in English) and which are presented today in the journal JAMA, published by the American Medical Association (AMA).
The new recommendations, which lower the starting age of mammograms recommended by the USPSTF by ten years, have been adopted due to the increase in cases of breast cancer registered in the age group of 40 to 50 years. The decision is part of an international trend to expand the age range in which early detection of breast cancer is offered.
In Europe, the European Commission already recommends mammograms from ages 45 to 74, and repeating them every two or three years. In Spain, only the Valencian Community, Galicia and Murcia currently follow the European recommendation.
The Spanish Society of Medical Oncology (SEOM) considers that “the European recommendations are correct,” declares oncologist César A. Rodríguez, president of the entity. “It cannot be said at this time that the benefits of screening in the 40 to 44 age group are well established. In the group of 45 to 49, they are.”
The majority of communities - including Catalonia and Madrid - currently limit early detection of breast cancer through public health to the age group of 50 to 69 years. Four other communities (Castilla-La Mancha, Castilla y León, La Rioja and Navarra) have increased the starting age to 45, but still do not offer it in the group of 70 to 74 years, in which the incidence of breast cancer is higher.
“It is a complex issue in which risks and benefits must be assessed,” declares Montserrat Muñoz, coordinator of the Breast Cancer Unit at the Hospital Clínic in Barcelona. “In the 40 to 50 age group there are fewer people affected than in the 50 to 69 age group,” so “many mammograms must be done on women who will not have pathology to detect a small number of cancers.”
The USPSTF of the United States has assessed that “the incidence [of breast cancer] in women aged 40 to 49 years increased gradually between 2000 and 2015” and that “it increased most notably between 2015 and 2019, with an average increase 2.0% annually,” according to the report presenting the new recommendations published in JAMA.
There is no data on the possible increase in breast cancer cases in women under 50 years of age in Spain.
The new USPSTF recommendations update previous ones, published in 2016, and are based on a review of currently available scientific evidence on mammography and epidemiological trends in breast cancer.
The recommendations are aimed at cis women with a medium risk of breast cancer, as well as trans men and non-binary people born anatomically as women. They are not applicable to people at high risk of breast cancer (for example, for hereditary reasons or having been exposed to high doses of radiation to the chest), for whom the early detection strategy must be assessed on an individual basis.
The group of experts recommends repeating mammograms every two years, rather than every year, because this reduces the number of false positives and maintains the ability to detect early tumors, when the prospects for successfully treating them are high. False positives - that is, the detection of a possible cancer that later turns out not to be cancer - require additional diagnostic tests and usually have a negative psychological impact on affected women.
The USPSTF estimates that performing biannual mammograms from ages 50 to 74 prevents 6.7 breast cancer deaths per thousand women (which is equivalent to saving one in every 149 women). If screening begins at age 45, 7.5 deaths are avoided per thousand women (one every 133). If you go ahead to 40, 8.2 are avoided per thousand (one every 122).
“The incidence of breast cancer increases with age and reaches its highest point between ages 70 and 74,” notes the USPSTF. In this age group, in which only a minority of communities in Spain offer breast cancer screening, biannual mammograms reduce breast cancer mortality by 22%.
Over the age of 75, the USPSTF refrains from recommending that mammograms continue to be performed because no studies have been done to evaluate whether the benefits outweigh the risks in this group.
The new recommendations are framed in “a trend to reduce the age at which mammograms begin; "It is something that requires an adequate provision of resources so that screening reaches the entire target population and that is being evaluated here in Catalonia," says Cristina Saura, a breast cancer specialist at the Vall d'Hebron hospital and the Institute of Oncology of Vall d'Hebron (VHIO).
Looking to the future, adds Saura, “we will evolve towards greater personalization of breast cancer screening programs, taking into account the individual risk of each person and incorporating new imaging and artificial intelligence technologies.”
