Hashimoto Thyroiditis Coexisting With Breast Fibroadenoma

A 34-year-old female with co-existing multiple breast nodules being treated simultaneously presented to the outpatient clinic with fatigue as the chief complaint which had progressively worsened over one year. Ultrasound showed a heterogeneous parenchymal ectopic pattern suggestive of thyroiditis, with no suspicion of nodules and cysts. Laboratory results showed raised levels of thyroid-stimulating hormone (TSH), serum anti-thyroglobulin antibody, and serum thyroid peroxidase antibody. Levothyroxine sodium at a dosage of 50 µg/day was prescribed to the patient, following which the patient had normal TSH levels on follow-up after two months. Simultaneously the patient was under investigation for the breast nodules that were seen as the patient's medical history when she presented to the endocrinology clinic. She was diagnosed with fibroadenoma with a canalicular pattern, without ductal atypia in both breasts and malignancy.