H. H. Shi1, C. R. McHenry1,2 1Case Western Reserve University School Of Medicine,Cleveland, OH, USA 2MetroHealth Medical Center,Cleveland, OH, USA
Introduction: A thyroid nodule in a patient with Graves’ disease has traditionally been thought to have a high risk of malignancy. The purpose of this study was to determine the frequency of a thyroid nodule in patients with Graves’ disease and the rate of malignancy in patients with a clinically apparent dominant thyroid nodule.
Methods: A retrospective review of all patients with Graves’ disease who underwent thyroidectomy from 1990-2016 was completed. The number of patients operated on with an associated dominant nodule was determined. Pathology reports were reviewed for documentation of incidental thyroid nodules. Age, sex, nodule size, thyroid uptake and scan, ultrasound findings, and fine needle aspiration biopsy results were determined. Incidental occult papillary microcarcinoma was not considered in the determination of rate of malignancy. Data was analyzed using Student’s t-test and Chi-square test.
Results: There were 218 patients with Graves’ disease who underwent thyroidectomy. 92 (42%) patients had one or more thyroid nodules documented on final pathologic examination of the thyroid gland, including 41 (19%) who had a clinically significant dominant nodule with a mean size of 3.0 ± 2.4 cm that was evaluated preoperatively with fine needled biopsy (n=25; benign 12, AUS 8, follicular neoplasm 3, suspicious for papillary cancer 1 and papillary cancer 1) and/or thyroid scintigraphy (n=18, 16 with a hypo- or isofunctioning nodule). Patients with a thyroid nodule were older (43 ± 13 yrs vs. 37 ± 11 yrs, p<0.001) and more likely to have an occult papillary microcarcinoma [5 (1%) vs. 1 (1%), p=0.039]. Only 2 (5%) of the 41 patients with a dominant nodule had a clinically significant thyroid cancer.
Conclusion: Thyroid nodules occurred in 42% of patients with Graves’ disease, however, most are incidental and clinically insignificant. Clinically significant nodules were present in 18% with a 5% rate of cancer. Our results show that patients with Graves’ disease and a thyroid nodule do not appear to have a higher rate of thyroid cancer than the general population with a thyroid nodule.
