[Follicular cancer of the thyroid: atypical presentation].

Follicular thyroid carcinoma usually presents as a thyroid nodule, with rare cases showing metastatic disease at diagnosis. We present a patient with follicular thyroid carcinoma who was diagnosed as a large pelvic metastatic mass with a biochemical profile of subclinical hyperthyroidism. She was treated with local-field radiotherapy, since surgical resection was not possible and radioiodine therapy would be of little benefit due to its large volume. She is currently in continuous remission two years from diagnosis.