All transgender people who have mammary glands must adhere to the breast cancer screening program under conditions very similar to those of cisgender women (those who identify with the sex assigned at birth). But administrative loopholes, insufficient training of health personnel and the lack of awareness of those affected exclude them from the early detection system, so that the risk of tumor development increases.
As a sign of femininity and body identity, the treatment of the mammary gland acquires special relevance for both men and trans women, who may be left out of cancer screening during the process of transition and gender adjustment, experts have warned the International Breast Cancer Center (IBCC), hyperspecialized center in breast cancer, based in Barcelona.
“It is no longer so uncommon to find a trans population that for some reason is outside the usual screening circuits”, explains Ignacio Miranda, head of radiology at the IBCC. “My last case – he explains – was that of a trans man who had not undergone a mastectomy, and despite the fact that he was already of age (from 50 years for women) he was outside the program because was administratively registered as male despite maintaining the mammary gland. The system does not identify her as a woman for the screening.”
This, transgender men who have not yet undergone a mastectomy for masculinization even though they have completed administrative gender reassignment, is one of two profiles that may be temporarily excluded from early detection. The other is that of trans women who have undergone hormonal treatments to develop breast tissue but have not yet completed the administrative procedure, so legally they are still men.
Gender reassignment treatments (hormonal or surgical) affect the mammary glandular tissue, a circumstance that can affect the risk of developing cancer. The baseline risk for trans women is similar to that of cis men, but with an added increase due to estrogen stimulation during hormone treatment. For their part, trans men have a similar risk of divorce to that of cisgender women, modified in this case by hormonal treatment with testosterone.
Breast surgeries, both mastectomies and breast augmentation, could also alter the risks of suffering from cancer.
There is little scientific evidence on the incidence of breast tumors in the trans population receiving hormone treatment. The most extensive study, carried out in the Netherlands on a sample of 2,260 women and 1,229 trans men, indicates that the former have a higher risk of cancer (46 times more) than cisgender men and that trans men have half the odds than cis women.
“With these data, it should be considered that transgender women enter the population screening programs for breast cancer, while transgender men undergoing masculinization surgery could be excluded”, points out Miranda. In this regard, it proposes three actions: that the Administration ensure that no one is excluded, that the trans population become aware of the importance of tests as cis women have done over the years and that health personnel have information, “that realities are changing and we will surely find a trans population that should be part of the programs”.
In this sense, it is estimated that in 2017 the transgender population in Spain was 10,000 individuals. But between 2017 and 2021, nearly 21,000 people were treated by units specializing in the treatment of gender identity, according to a report by Confluència Moviment Feminista.
Who should be included in the screening? The radiology and endocrinology societies of the USA have developed guidelines and indications regarding the matter. “For practical purposes, they are the same as in the population of cis women”, points out Dr. Miranda: from the age of 50. Trans women who have been on hormone treatment for at least five years and trans men who have not had breast surgery, i.e. who retain their birth female breasts.
The Canadian Cancer Society recommends mammography every two years for transgender women between the ages of 50 and 69 who have received hormone treatment, as they develop considerably the mammary glandular tissue, with proliferation of ducts, lobules and acini identical to those of the female breast . In addition, estrogen is a significant risk factor for breast cancer. However, the few studies that have been done on breast tumors in the case of the trans population have important methodological limitations that prevent definitive conclusions from being drawn.