Endocrine Abstracts

Objective: We present a 62-year-old male who had manifested with gynaecomastia to a surgeon. He was able to avoid mastectomy when it was found that his gynaecomastia was being caused by asymptomatic hyperthyroidism.

Case report: A 62 years male presented to a surgeon with 6 months history of gradual enlargement of both of his breasts primarily for cosmetic reasons. The surgeon had planned bilateral mastectomies pending funding from the primary care trust. His tests revealed: The blood results were FT4 58.3 pmol/l (8–20), FT3 24.3 pmol/l (2.5–6), TSH 0.010 mU (0.2–4.0), testosterone 37.6 nmol/l (8–27), SHBG >180 nmol/l (15–55), FSH 19.9 IU/l (1–10), LH 21.9 IU/l (1–10), oestadiol 374 pmol/l (<130), prolactin 152 mU/l (50–700), PSA 0.4, HCG 0 IU/l (<3), cortisol 522 nmol/l (184–623), normal FBC, LFTs, U&Es. The mammogram confirmed presence of bilateral gynaecomastia more on the left breast. Ultrasound of testes and CT scan of adrenal gland was normal. The patient treated with carbimazole 40 mg daily. After 2 months, his blood results revealed euthyroid picture with FT4 16.9 pmol/l, FT3 4.9 pmol/l and TSH of 0.04 and normal gonadotrophins and sex steroids. The patient has significant decrease in size of his breasts and this confirmed by repeat mammogram. We expect his breasts to regain their normal size in due course.

Conclusion: Gynaecomastia can be the only manifestation of hyperthyroidism and in many cases patient may not be able to appreciate symptoms suggestive of hyperthyroidism but most men are able to note any change in their breast size. Therefore, it is essential to include thyroid function in the work up of any patient with gynaecomastia. Recognition of this uncommon presentation in a common disease like hyperthyroidism will avoid unnecessary intervention, like our patient was saved from mastectomy.