Follicular thyroid carcinoma and mediastinal goiter in a case of situs inversus viscerum.

A 55-year-old woman with total situs inversus viscerum was subjected to total thyroidectomy for a well-differentiated follicular thyroid carcinoma. After surgery the patient remained euthyroid for two months and serum TSH did not rise. A whole body scan with iodine-131 (131I) showed mediastinal uptake. A chest computed tomography visualized a sequestered substernal goiter. Upon the patient's refusal to undergo surgery, she was treated with 150 mCi of 131I. A further dose of 100 mCi of 131I was administered six months later. Ten years after treatment, the patient is still alive and disease-free.