A. R. Marcadis1, S. Liu1, M. Rodriguez1, J. I. Lew1 1University Of Miami Miller School Of Medicine,Division Of Endocrine Surgery,Miami, FL, USA
Introduction: Patients who undergo surgical resection for benign thyroid disease may have incidental papillary thyroid cancer (PTC) discovered on final pathology. The incidence of PTC has historically been between 5 to 10% in patients treated operatively for benign thyroid disease. This study attempts to determine if there are any preoperative factors for incidental PTC that may help determine the extent of thyroidectomy in patients with benign thyroid disease.
Methods: A retrospective review of prospectively collected data of 1822 consecutive patients who underwent thyroidectomy at a single institution was performed. Of these patients, 355 underwent surgical resection for benign thyroid disease. Indications for surgery were obstructive or compressive symptoms (n=142), hyperthyroid symptoms including Graves’ disease (n=111), goiter size >4 cm (n=92), and substernal goiter (n=10). Patients with indeterminate or malignant preoperative FNA results were excluded. Of all patients, 74% (n=263) underwent total thyroidectomy, and 26% (n=93) underwent a lobectomy. Benign final pathology included nontoxic multinodular goiter (MNG) (n=136), toxic MNG (n=75), nontoxic solitary nodule (n=67), toxic solitary nodule (n=21) and Graves’ disease (n=6). Incidental cancers were defined as PTC discovered only upon final pathology. Age and gender were examined to determine if certain subsets of these categories had a higher indication for incidental cancers, using a two-tailed Z-test at a significance of 0.05.
Results: Overall, 14% (50/355) of patients who underwent surgical resection for benign thyroid disease had incidental PTC on final pathology. Women constituted 90% (n=322) of patients. There was no significant difference between incidental PTC rates in women (14%, 46/322) and men (12%, 4/33). Patients treated for obstructive symptoms had the highest incidental PTC rate at 19% (27/142), followed by goiters >4 cm at 15% (14/92), hyperthyroidism at 8% (9/111). Patients <50 years of age with benign indications for surgical resection had incidental PTC rates of 18% (33/187) compared to a 10% (17/169) incidental PTC rate for patients >50 years of age. Patients <50 years of age with benign thyroid disease had a significantly higher percentage of incidental PTC on final pathology than those patients >50 years of age (p=0.0394).
Conclusion: There is a higher than expected rate of incidental PTC in patients who undergo operations for benign thyroid disease, especially in patients <50 years of age. Therefore, total thyroidectomy by an experienced surgeon should be strongly considered when managing benign thyroid disease in such patients.