Papillary carcinoma thyroid metastases presenting as thyrotoxicosis post thyroidectomy - A case report

Thyrotoxicosis can occur in the setting of differentiated thyroid cancer due to functioning metastases. Here, we report a case of a 63 year old woman with papillary carcinoma thyroid who underwent total thyroidectomy and defaulted for further scheduled treatment with high dose radioactive iodine therapy. 2 years after total thyroidectomy, she presented with signs and symptoms of thyrotoxicosis and a scalp swelling on the right side of frontal region. Excision biopsy revealed metastatic deposits of papillary carcinoma thyroid. Even after withdrawal of thyroxine, her serum thyrotropin did not rise and thyroglobulin levels were high, raising the suspicion of high volume tumour burden. I-131 whole body scan was done and it revealed radio iodine avid cervical lymph nodes along with functioning lung and skeletal metastases.