Aggressive Fibromatosis of the neck initiated after thyroidectomy

We describe the case of a 44-yr-old woman, who 2 yr after thyroidectomy for a multinodulare goiter with a follicular adenoma showed a rapidly growing mass of the neck causing dysphagia and moderate pain. Fine needle aspiration biopsy revealed the presence of fibroblast-like cells, partially with atypical features and no colloid: the cytological diagnosis was suspicious for an indeterminate (mesenchymal) neoplasm. Histological diagnosis, after extensive surgery indicated aggresive fibromatosis. Immunohisto-chemistry was positive for vimentin and negative for thyroglobulin. After surgery, muclear magnetic resonance showed a persistent mass of approximately 2 cm; dysphagia and pain persisted. Therefore, the patient received external radiation therapy (total dose 60 Gy) with clinical benefit. The patient is without symptoms 1 yr after surgery. (J. Endocrinol. Invest. 29: 78-81, 2006).