Abstract
BACKGROUND: Aggressive fibromatosis (AF) is a benign tumor that usually has a locally aggressive and recurrent disease course. Reports of association between AF and malignancies have been reported infrequently. CASE: We report a case of a 49-years lady who had papillary thyroid carcinoma associated with a distinct desmoid tumor occurring concurrently on the right side of the neck. Initial management comprised of total thyroidectomy followed by radio-iodine therapy and desmoid tumor resection. Recurrent AF developed at the same site as before after 2 years of resection. The recurrent tumor was managed with sorafenib, the patient responded with a resolution of symptoms, and the tumor remained stable. Beta-catenin mutation done by Sanger sequencing was negative in the tumor specimen. CONCLUSION: AF can occur as a separate tumor in association with PTC. If symptoms are not life-threatening medical management may be a better choice in management.