Risk stratification of 282 differentiated thyroid cancers found incidentally in 1369 total thyroidectomies according to the 2015 ATA guidelines; implications for management and treatment

Introduction The purpose of this study was to evaluate the incidence of incidental differentiated thyroid carcinoma in thyroid operations for a benign preoperative diagnosis, to identify the risk factors involved and to risk stratify the cancer patients according to the 2015 American Thyroid Association (ATA) guidelines. Materials and methods The study was a retrospective review of all thyroidectomy operations performed in a single institution (January 2004 to January 2009). We excluded patients with a preoperative diagnosis of thyroid malignancy. Results Incidental differentiated thyroid carcinoma was diagnosed in 282/1369 patients (21%). The incidental group had a significantly higher number of males (19% vs 14%, P = 0.033) and a higher number of patients with histopathological evidence of thyroiditis (35% vs 25%, P = 0.004). There was a higher number of lymph nodes present in the incidental group but numbers did not reach statistical significance (17% vs 13%, P = 0.079). There were 270 cases in the ATA...