Optimal timing of surgery for differentiated thyroid cancer in pregnant women

Differentiated thyroid cancer (DTC) is the second most common cancer diagnosed in pregnant women, but there is no consensus as to whether surgery should be performed during pregnancy or after delivery.

We retrospectively reviewed the records of 45 patients with DTC operated on during pregnancy or within 1 year after delivery, and we compared the clinicopathological features and outcomes of the patients operated during pregnancy (group A, n = 24) and the patients operated after delivery (group B, n = 21).

All 45 patients were histologically diagnosed with well-differentiated papillary thyroid cancer. Nineteen (79 %) of the 24 patients in group A underwent thyroidectomy during the second trimester. No complications associated with surgery or general anesthesia were reported in either group. There were no significant differences between the two groups in terms of age, tumor size, incidence of lymph node metastasis, or incidence of extrathyroidal extension. No distant metastases were detected in any of the patients. Two small for date infants (8.3 %) and 2 heavy for date infants (8.3 %) were delivered in group A, but only 1 small for date infant (4.7 %) was delivered in group B. There were no miscarriages, and none of the infants in either group had birth defects. Because 3 patients in group A and 1 patient in group B experienced a local recurrence, salvage surgeries were performed.

Although thyroid surgery was performed safely in the second trimester, surgery after delivery was also acceptable. Surgery after delivery is recommended for most patients with non-aggressive DTC.