November 11, 1996

Management of Thyroid Nodules in Pregnancy

Author Affiliations

From the Division of Endocrinology/Metabolism and Internal Medicine (Drs Tan, Gharib, and Bahn), Section of Surgical Pathology (Dr Goellner), and Division of Gastroenterology and General Surgery (Dr van Heerden), Mayo Clinic and Mayo Foundation, Rochester, Minn.

Arch Intern Med. 1996;156(20):2317-2320. doi:10.1001/archinte.1996.00440190059007

Background:  Disorders of the thyroid are common in pregnancy. In particular, a thyroid nodule is frequently discovered before or during pregnancy.

Objective:  To develop guidelines for the management of thyroid nodules during pregnancy.

Methods:  We reviewed the cases of 40 pregnant patients with thyroid nodules evaluated during a 10-year period. Cytological findings were compared with available histological findings, and concordance rates were determined. The rank sum test was used for statistical analysis.

Results:  Fine-needle aspirations of thyroid nodules in 62% of patients were benign cytologically (25 patients). Of 8 patients with negative cytological results who had thyroidectomy, all had benign disease histologically (100% concordance rate). Cytological findings of papillary cancer (3 patients) strongly correlated with final histological diagnosis (100% concordance rate), whereas papillary cancer was confirmed histologically in only 2 of 4 patients with cytological findings suspicious for this disease (50% concordance rate). All 3 nodules with cytological findings suspicious for follicular neoplasm were benign adenomas histologically. Of 2 nodules suspicious for Hürthle cell neoplasm, 1 was Hürthle cell adenoma and the other was Hürthle cell carcinoma (100% concordance rate). Thyroidectomy during the second trimester of pregnancy or the early postpartum period was successful.

Conclusions:  The approach to thyroid nodules in pregnancy should be similar to that for nonpregnant patients. Thyroidectomy should be performed (1) during the second trimester for malignant lesions and cytological findings suspicious for papillary cancer and (2) in the postpartum period for cytological findings suspicious for follicular neoplasm.Arch Intern Med. 1996;156:2317-2320