Five new cases of breast cancer in transsexual persons

Abstract

Cross-sex hormone treatment of transsexual people may be associated with the induction and growth stimulation of hormone-related malignancies. We report here five cases of breast cancer, three in female-to-male (FtoM) transsexual subjects and two in male-to-female (MtoF) transsexual subjects. In the general population the incidence of breast cancer increases with age and with duration of exposure to sex hormones. This pattern was not recognised in these five transsexual subjects. Tumours occurred at a relatively young age (respectively, 48, 41, 41, 52 and 46 years old) and mostly after a relatively short span of time of cross-sex hormone treatment (9, 9-10 but in one after 30 years). Occurrence of breast cancer was rare. As has been reported earlier, breast tumours may occur in residual mammary tissue after breast ablation in FtoM transsexual people. For adequate treatment and decisions on further cross-sex hormone treatment it is important to have information on the staging and histology of the breast tumour (type, grade and receptor status), with an upcoming role for the androgen receptor status, especially in FtoM transsexual subjects with breast cancer who receive testosterone administration. This information should be taken into account when considering further cross-sex hormone treatment.

Cancer in Transgender People: Evidence and Methodological Considerations

“…In transmen, published case reports describe cancers of the breast, ovaries, cervix, vagina, and endometrium (17,18,34,35,44,45,(64)(65)(66)(67)(68).…”

“…The current literature includes 15 reported cases of breast cancer in transwomen who received estrogen therapy (43)(44)(45)(46)(47)(48)(49)(50)(51)(52)(53). Most reported cases were relatively young, with some patients presenting in their early 30s.…”

“…There were 7 reported cases of breast cancer in transmen who received gender affirmation therapy (44,45,(64)(65)(66). All 7 cases received testosterone therapy, and 4 underwent a mastectomy prior to diagnosis.…”

Breast cancer in male-to-female (MtF) transgender patients: is hormone receptor negativity a feature?

“…However, the authors were cautious about their findings, which were based on relatively few incident cases 9 12. They also point out that the study's follow-up period is still relatively short and it remains to be seen whether more patients will present over the next decade, with prolonged exposure to estrogen and from ageing.…”

“…These reports include four cases from an Amsterdam gender clinic following 2307 MtF transgender patients since 1975 9 12. This led the authors of the Amsterdam follow-up cohort study to conclude that there is insufficient evidence to suggest an increased risk of breast cancer in MtF transgender individuals receiving estrogen therapy 9…”