Benign phyllodes tumour in a transgender woman receiving hormonal therapy

We present a case of a transwoman taking hormonal feminisation therapy for over 20 years, who underwent surgical excision of a benign phyllodes tumour of the breast. Hormones progesterone and oestrogen act on breast epithelium to increase proliferation. For ciswomen, endogenous and exogenous oestrogen exposure over a lifetime is associated with increased risk for certain benign and malignant breast pathologies. Transwomen taking hormonal therapy may also be at an increased risk of breast disease.