IS THYROID-HORMONE USEFUL TO PREVENT NODU LAR RECURRENCE AFTER HEMITHYROIDECTOMY

The frequency of recurrence of thyroid nodule following hemithyroidect omy is variably assessed according to the individual authors. Few stud ies put a figure to ultrasanographic recurrence, clinical recurrence o nly being taken into account: its percentage ranges from IO to 20 %, i ncreasing with the time lapse after thyroidectomy. Attempts to prvent recurrence are based on an approach of the physiopathology of thyroid nodules. Clinical and epidemiological studies of patients wioth goiter s suggest that TSH may play a role in the generation of goiters, as ha s been confirmed by experimental work. However, several other local au tocrine or paracrine growth factors may also be involved in the genera tion of goiters, including IGF I and IGF II (Insulin Growth Factors), FGF (Fibroblast Growth Factor), EGF (Epidermal Growth Factor), TGFB (T ransforming Growth Factor beta). On the basis of the possible role of TSH in goiter generation, some teams have advocated a postoperative co urse of thyroid hormones aimed at limiting thyreostimulin production. The studies, most of them retrospective studies, do not alow drawing a meaningful conclusion because their methods are open to criticism and the results observed are disparate. On a whole,although thyroid hormo ne therapy is often used after hemithyroidectomy, the physiopathologic al bases of its prescription are disputable, and the results obtained in terms of recurrence of nodules are not conclusive enough. It is the refore desirble to set up randomized studies.