Are large thyroid nodules classified as benign on fine needle aspiration more likely to harbor cancer?

Abstract

Introduction: Our aim was to investigate whether benign thyroid nodules ≥ 4 cm have a higher malignancy rate.

Methods: A retrospective review of patients with a nodule and a benign FNAB who underwent thyroidectomy was completed. Patients were divided into two groups; nodule size: < 4 cm or ≥4 cm, and clinical factors, nodule size and rates of malignancy were compared.

Results: 337 patients underwent thyroidectomy: 99 had nodules <4 cm (2.8 ± 0.58 cm) and 238 had nodules ≥ 4 cm (5.9 ± 1.97 cm). Seven (2.1%) patients had cancer, 2 (2.0%) with a nodule < 4 cm and 5 (2.1%) with a nodule ≥ 4 cm (p = 0.962). There was no difference in clinical factors between groups (p > 0.05).

Conclusion: There is no difference in rates of malignancy for nodules < 4 cm or ≥ 4 cm. Thus, thyroidectomy should not be recommended based solely on nodule size.

Keywords: False-negative rate; Fine-need aspiration biopsy; Nodular thyroid disease; Thyroid cancer; Thyroidectomy.