Case Report of Graves’ Disease in a 45-Year-Old Woman Secondary to Herceptin Treatment for Breast Cancer

Abstract

ABSTRACT

Graves’ disease is the commonest cause of thyrotoxicosis characterised by ophthalmopathy with proptosis, chemosis, or conjunctival injection; pretibial myxedema; and thyroid acropachy. It is an autoimmune disease which can be genetic or influenced by coexisting environmental factors like exposure to anticancer drugs like immune checkpoint inhibitors. The incidence rate of breast cancer is increasing attributed to rising risk factors and screening for breast cancer and the mortality rate decreasing attributed to recent advances in cancer treatment. However, there are side effects attributed to these treatments modalities manifesting in various forms in breast cancer survivors which is reflected in the patient in this case study.

CASE PRESENTATION

This patient who was exposed to monoclonal antibody trastuzumab and developed worsening proptosis, palpitation, insomnia, low TSH and elevated thyroxine and triiodothyronine with the progression of Herceptin therapy.  Graves disease was confirmed  following elevated thyroid antibodies in which symptoms abated with the conclusion of trastuzumab treatment and commencement of antithyroid medications (Carbimazole and Propranolol). She is currently euthyroid within two years of antithyroid treatment and follow-up.

CONCLUSION

There is a high probability of the stimulation of TSH receptors by trastuzumab in breast cancer patients. Early screening for thyroid function for all breast cancer patients, funding of research in the treatment of breast cancer patients and survivors.

Keywords: Graves’ disease, Thyroid antibodies, AIT, breast cancer, Herceptin