Difficulties of gender affirming treatment in trans women with BRCA1+ mutation: A case report

Endocrinol Diabetes Nutr (Engl Ed). 2024 Mar;71(3):144-148. doi: 10.1016/j.endien.2023.12.002.

Abstract

Gender affirming treatment in transgender women is based on a combination of antiandrogens and estrogens, with the latter maintained over the long term. When prescribing these treatments, we must consider the possibility of developing estrogen-dependent breast cancer. In transgender women, a breast cancer incidence of 4.1 per 100,000 has been estimated, which would increase the risk by 46% in relation to cisgender men but decrease it by 70% in relation to cisgender women. It is known that certain gene mutations such as BRCA1 imply an increased risk of breast cancer, but at present the risk in transgender women with BRCA1 treated with estrogens is not well established. We present the case of a transgender woman with a family history of breast cancer and BRCA1 mutation and the therapeutic decisions made in a multidisciplinary team. Following this case, we review and discuss the published literature.

Keywords: BRCA1; Breast cancer; Cáncer de mama; Estrogens therapy; LGBT; Mujer transgénero; Terapia estrogénica; Transgender woman.

Publication types

  • Case Reports
  • Review

MeSH terms

  • BRCA1 Protein / genetics
  • Breast Neoplasms* / drug therapy
  • Breast Neoplasms* / genetics
  • Estrogens
  • Female
  • Humans
  • Male
  • Mutation
  • Transgender Persons*
  • Transsexualism* / drug therapy

Substances

  • Estrogens
  • BRCA1 protein, human
  • BRCA1 Protein