Management and follow-up of thyroid cancer in pregnant women

SUMMARY Thyroid cancer, the most common endocrine malignancy, is often detected in young female patients. Therefore, pregnancy following thyroid cancer is not infrequent, and about 10% of thyroid cancers occurring during the reproductive years are diagnosed during pregnancy or in the early post-partum period. Differentiated thyroid cancer (DTC) in young people generally has an excellent prognosis, and disease-free survival among women with DTC diagnosed during pregnancy may not differ from that in age-matched non-pregnant women with similar disease. However, thyroid cancer detected during pregnancy may cause anxiety about the optimal timing of recommended treatments and about both maternal and neonatal morbidity, as weel as pregnancy following a diagnosis of thyroid cancer obviously needs both maternal and foetal management. The main objectives in clinical monitoring of pregnant thyroid cancer patients are: 1) to reach an adequate balance of maternal calcium and thyroid hormones that is absolutely required by the foetal central nervous system for normal maturation; 2) to maintain optimal levels of maternal thyroxin to avoid possible recurrence or spread of disease; and 3) to perform safe follow-up visits for the mother and to plan further therapy when needed. Data from a review of the literature and the authors' own experience show that in patients undergoing either suppressive or substitutive thyroxine therapy foetal thyroid growth is normal at ultrasound study, newborn thyroid status is normal, and the incidence of maternal morbidity is not influenced by the pregnancy. In this review, the authors underline that regular adjustment of levo-thyroxine and calcium therapy is of outmost importance for both maternal and foetal well-being and offer some insight, very interesting from a practical point of view, to provide a clear and simple pathway for the management of pregnancy-associated thyroid cancer.