Endocrine Abstracts

Introduction: Thyroid cancer is one of the common malignancies diagnosed in pregnancy and the management of thyroid nodules in pregnancy is the same as in non-pregnant patients. Ultrasound thyroid and FNA are necessary in the investigations of any thyroid nodule.

Case presentation: A 39-year-old woman of Eastern European descent presented to the joint obstetric-endocrine clinic complaining of dysphagia and swollen neck at 34 weeks gestation. Her past medical history included hypothyroidism, psoriatic arthritis and depression. Family history was noteworthy for thyroid cancer – her mother had thyroid cancer treated with total thyroidectomy and radioactive iodine therapy. In addition, the woman herself was 2 years of age and exposed to the Chernobyl nuclear disaster. An Ultrasound (USS) thyroid revealed a right-sided solid thyroid nodule (U3-U4) measuring 9x8x1 mm and fine needle aspiration (FNA) confirmed follicular lesion Thy3F. She had a successful right hemithyroidectomy 4 weeks postpartum. The histology confirmed classic features of papillary carcinoma 1 mm staged as pT1b N0 R0. She was discussed in the thyroid MDT and the outcome was for TSH suppression, surveillance and not for completion thyroidectomy.

Discussion: Pregnant women with thyroid cancer can be asymptomatic and studies have suggested pregnancy increases the risk of developing new thyroid nodules. Pregnancy can also cause an increase in the size of pre-existing thyroid nodules by up to 50%. Development of new nodules is up to 20%. A detailed history of suspected thyroid nodules should be taken including a family history of thyroid cancer. A thorough examination of the thyroid gland should be performed followed by an USS thyroid to characterize the thyroid nodule. FNA is safe in pregnancy and can be performed in any trimester. Counselling is an important part of the management of thyroid nodules in pregnancy to allay anxiety and distress. Regular (4-6 weeks) monitoring of thyroid function tests is essential and the FT4, FT3, TSH range is trimester dependent.

Conclusion: The management of thyroid nodules in pregnancy depends on whether the nodules are benign or malignant and if the pregnant mother is symptomatic. For malignant nodules, surgical intervention is ideal in the second trimester or post-partum. Hence, an MDT approach is important. The TSH range should be maintained at 0.2-2.0mIU/l.