Endocrine Abstracts

An 82-year-old male was referred to the breast clinic with a four month history of painful right gynaecomastia (GM), without nipple discharge. A 4 cm plaque of tender, soft tissue was palpable. Physical examination and external genitalia were normal. There was no relevant drug history. Prolactin, Testosterone (T), CXR, Ultrasound and FNA of the breast were normal. LH 13.0 IU (1.5-10.0) and FSH 18.1 IU (1.5-10.0) were raised. FT3 was raised at 7.3 pmol/L (3.5-5.5) with TSH suppressed to <0.03mU/l. He was later re-referred after 10 months to Medicine for the Elderly, with night sweats, painful right GM and no other features of hyperthyroidism. FT3 was 7.4 and Carbimazole was commenced. Within four months, the night sweats and right GM had resolved. He was referred to the Endocrine Clinic for further assessment. He was hypothyroid, with a TSH of 18.64mU/L. Antithyroid peroxidase antibody was 241 IU/L, Testosterone was 7.3 nmol/L (9.0-29.0) and Oestradiol (E2) <140 pmol/L (0-180). Carbimazole was stopped and at review right breast tenderness recurred as well as hyperthyroidism with a FT3 6.0 and TSH <0.03. Carbimazole was restarted and referral for I131 was arranged. Thyroxine replacement was started for post radioiodine hypothyroidism to maintain euthyroid status. The right GM had completely resolved and has not recurred.GM is a well recognised, but rare feature of hyperthyroidism. We have not seen recurrent, unilateral, painful GM as a feature of relapsing hyperthyroidism and have not found similar cases reported in the literature. Hyperthyroidism modulates androgen/oestrogen balance by direct effects on aromatization and via changes in SHBG. The male breast, which is sensitive to subtle changes in T/E2 ratio, may be more likely to be stimulated in an elderly male with hypogonadism. Recognition of this association is clinically relevant to avoid unnecessary investigations, undue patient anxiety and appropriate early treatment.