M.R. Guido1, V. DeTrolio2, C. Saghira2, C. Chen3, T.M. Vaghaiwalla4, J.I. Lew4 1University of Miami Leonard M. Miller School of Medicine, Miami, FL, USA 2University of Miami Leonard M. Miller School of Medicine, DeWitt Daughtry Department Of Surgery, Miami, FL, USA 3University Of Miami, Department Of Industrial Systems Engineering, Miami, FL, USA 4University of Miami Leonard M. Miller School of Medicine, Division Of Endocrine Surgery, DeWitt Daughtry Department Of Surgery, Miami, FL, USA
Introduction: Nontoxic uninodular goiter (UNG) is a common thyroid condition often referred to surgeons for compression symptoms, nodular disease, and concern for thyroid cancer (TC). Preoperative assessment including thyroid ultrasound (US), with or without fine needle aspiration (FNA) biopsy, is part of the work up of thyroid nodules to evaluate for malignancy. This study examines the rate of incidental TC for patients undergoing thyroid surgery for nontoxic UNG with presumed benign disease.
Methods: A retrospective review of prospectively collected data of 553 UNG patients treated with thyroid lobectomy between 2009 and 2022 was performed. We queried patients who were >18 years, had a preoperative US, and no prior FNA. Patients were excluded if they had a prior history of TC, and prior thyroid or parathyroid surgery. Factors including age, gender, symptoms, US features, surgical outcomes, and final pathology were reviewed. Patients were divided into two subgroups based on final pathology: those with benign nontoxic UNG and those with UNG and TC. Chi-square tests were used for independence among categorical variables and comparisons were based on T-tests. A p-value of <0.05 was considered statistically significant.
Results: A total of 346 UNG patients met inclusion criteria, of which 84.3% (n=292) were women and 15.7% (n=54) were men. The mean age at the time of surgery was 47 (+/- 13) years. Patients were referred for obstructive symptoms (21.4%; n=74) including dysphagia (n=63), dyspnea (n=19), and voice changes (n=19). On preoperative US, mean nodule size was 2.6 cm (+/- 1.25 cm). When comparing patients with benign UNG to patients with TC, no significant differences were observed on US for nodule size, microcalcifications, echogenicity, or border irregularity (p=>0.05). When examining thyroidectomy-specific outcomes, there were no differences between the two cohorts for transient recurrent laryngeal nerve (RLN) injury (1.7% vs. 0.6%), permanent RLN injury (0.6% vs. 1.2%), neck hematoma (0.6% vs. 0%), surgical site infection (0.6% vs. 0%), or seroma (1.1% vs. 0.6%) (p=>0.05). There were no 30-day readmissions. On final pathology for the entire cohort, 52% (n=180/346) were diagnosed with benign disease and 48% (n=166/346) had TC. The rate of TC with a tumor size >1 cm was 32% (n=113/346) compared to 68% of patients with TC <1 cm. Among the 166 TC patients, 92% (n=153) had papillary thyroid carcinoma (PTC) and 8% (n=13) had follicular carcinoma.
Conclusion: This study found that 32% of patients with nontoxic UNG undergoing lobectomy for presumed benign thyroid disease had incidental thyroid carcinoma >1 cm. Among patients with a TC diagnosis, more than 90% were PTC on final pathology. Patients with nontoxic UNG had excellent thyroidectomy-specific outcomes for benign disease and TC when performed by high-volume thyroid surgeons. These findings may inform surgeons during patient counseling and surgical planning for nontoxic UNG.