Incidentally discovered papillary carcinoma of the thyroid: value of ultrasonographic follow-up. A case-report.

Incidentalomas of the thyroid are common small nodules found occasionally during imaging procedures. Their pathological nature is generally benign, but about 4% may harbour malignant tissue. Most current studies only suggest clinical follow-up, but there are no data about the natural history of malignant incidentalomas. The authors describe a patient with multiple incidentaloma of the thyroid submitted to fine-needle aspiration biopsy because his larger nodule grew 50% in 3 months at ultrasonographic follow-up. The cytological examination suggested thyroid malignancy in this nodule and surgical pathology showed multicentric papillary carcinoma. This case suggests that the larger diameter of a malignant incidentaloma may change rapidly. If more time had been spent before repeating the ultrasonography, the volume could have changed even more and the prognosis could have been changed as indicated by most prognostic score indexes.