Management of differentiated thyroid cancer diagnosed during pregnancy.

OBJECTIVE To assess the outcome of thyroid cancer diagnosed during pregnancy. DESIGN Retrospective analysis of patients diagnosed between 1949 and 1997 with thyroid cancer presenting during pregnancy. RESULTS Nine women with a median age of 28 years were identified. A thyroid nodule was discovered by the clinician during routine antenatal examination in four cases, the remainder had noted a lump in the neck. In all patients, the nodule was reported to almost double in size during the pregnancy. One patient underwent subtotal thyroidectomy during the second trimester; eight were operated on within 3 to 10 months from delivery. Total thyroidectomy was performed in five and subtotal thyroidectomy in four. All tumours were well differentiated and ranged in size from 1 to 6 cm. OUTCOME The median follow-up was 14 years (5-31 years). One patient relapsed locally requiring further surgery. One patient developed bone metastases dying 7 years after presentation; her planned treatment had been delayed because of an intervening pregnancy. Eight of the original cohort of patients are currently disease free. CONCLUSIONS Differentiated thyroid cancer presenting in pregnancy generally has an excellent prognosis. When the disease is discovered early in pregnancy, surgery should be considered in the second trimester but radioiodine scans and treatment can be safely delayed until after delivery. In all cases, treatment should not be delayed for more than a year.