Treatment of Hyperthyroidism Associated with Thyrotropin-Secreting Pituitary Adenomas with Iopanoic Acid

Abstract

TSH-secreting tumors comprise less than 2% of all pituitary adenomas. All patients present with hyperthyroidism with a detectable TSH level, and a majority have macroadenomas. Oral cholecystographic agents (e.g. iopanoic acid) potently inhibit the activation of T(4) to the more potent T(3). They have been used successfully to treat primary thyroidal hyperthyroidism and thyroxine overdose. However, they have not been employed in the treatment of central hyperthyroidism. We report, herein, the first two patients with thyrotropinomas, in whom iopanoic acid (Telepaque) has been used perioperatively to safely and rapidly achieve euthyroidism. In case 1, free T(3) index improved from a value of 634 to 175 (normal range 78-162) after 3 d of therapy with iopanoic acid. In case 2, free T(3) by dialysis improved from 697 pg/dl (10.7 pmol/liter) to 195 pg/dl (3.0 pmol/liter) (normal range 210-440 pg/dl; 3.2-6.7 pmol/liter) after 7 d of therapy with iopanoic acid.

Refractory Transposing Hyperthyroid Disorder Inducing Tsh-secreting Pituitary Adenoma: A Case Report and Literature Review

“…Nevertheless, combined treatment by means of surgical excision and external radiation attains remedy in 50-80% of patients though comparisons of surgical excision and combined treatment exhibited no substantial transformation in the magnitudes of treated, better-quality, and untreated patients (14,28,29). Many authors (14,27,30,31) support medical management option with somatostatin analogue octreotide or lanreotide hence this treatment modality has yielded positive results. Furthermore, studies (14,32) have proven that octreotide accomplishes PA regression in about 38.5% of cases.…”

Tratamiento médico del hipertiroidismo

“…La cabergolida ha sido empleada en algunos pacientes con resultados variables, que consisten en la supresión parcial de TSH en la mayoría de los casos [15]. En pacientes con hipertiroidismo muy severo se han descrito casos de rápida consecución del eutiroidismo utilizando ácido iopanoico, a la dosis de 500 mg dos veces al día durante 7 a 11 días [17]. En casos de contraindicación quirúrgica o rechazo de la misma, está indicado el tratamiento radioterápico y/o análogos de la somatostatina.…”

Adénomes hypophysaires à TSH ou adénomes thyréotropes

“…Avant le traitement chirurgical d'un adénome thyréotrope, un contrôle de la thyrotoxicose préopératoire doit être obtenu par les ß-bloquants, les antithyroïdiens de synthèse, l'iopodate [17] ou les analogues de la somatostatine [18] …”