An undiagnosed TSH-secreting pituitary macroadenoma found during pregnancy

Summary Thyroid stimulating hormone (TSH)-secreting pituitary adenoma (TSHoma) is an uncommon cause of thyrotoxicosis, and is even rarer when found during pregnancy. Our patient presented with thyrotoxicosis accompanied by an inappropriately normal TSH level at 10 weeks of gestation during work-up of surgical termination of pregnancy (STOP). Subsequent investigations performed after STOP confirmed the presence of a TSH-secreting pituitary macroadenoma. She was initially treated with anti-thyroid drugs for biochemical control, followed by trans-sphenoidal surgery after STOP had been performed. Her thyroid function completely normalized after the trans-sphenoidal surgery. Our case illustrated the importance of recognizing the syndrome of inappropriate TSH secretion and highlighted several pregnancy-related aspects in the diagnosis and management of TSHoma during pregnancy. Learning points: This case report illustrates the need to raise awareness in recognizing the syndrome of inappropriate TSH secretion. Illustrate the different hormone tests available for reaching the diagnosis of TSH-secreting pituitary adenoma. Highlight the physiological changes in the thyroid status during pregnancy and the importance of using trimester-specific reference ranges for assessment of thyroid function during pregnancy. Describe the challenges in the management of TSH-secreting pituitary adenoma during pregnancy.

TSH secreting pituitary tumor — an experience of 20 years follow-up

Thyrotropinoma is a rare pituitary tumor that causes the development of thyrotoxicosis syndrome as a result of hyperproduction of thyroid stimulating hormone (TSH). In the Russian literature over the past 10 years, one case of thyrotropinoma in a child, four cases of TSH-producing pituitary adenoma in women and only one in a man have been described. The article presents a unique clinical case of a 20-years history of observation of a patient with TSH-oma. The rarity of this disease led to the fact that it took more than 10 years to make a correct diagnosis. The first operation of thyroid gland was performed before the diagnosis of pituitary adenoma and inappropriate TSH secretion syndrome. That right hemithyroidectomy was supposed to cure a toxic adenoma of thyroid gland. The diagnosis of thyrotropin-secreting piruitary tumor was established only after 6 years even after finding a combination of pituitary adenoma and thyrotoxicosis. After that, the patient steadfastly refuses neurosurgical treatment, despite the presence of macroadenoma with intrasellar growth. The therapy with somatostatin analogs led to patient’s intolerance with gastrointestinal side effects and hospitalization for acute pancreatitis. The absence of the therapy due to low compliance led to long-term persistence of thyrotoxicosis. The absence of signs and symptoms of expanding tumor mass (visual field defects, loss of vision, headache, partial or total hypopituitarism) demonstrates the slow growth of this kind of pituitary tumor. The long-term effect of elevated TSH levels led to diffuse goiter with compression of the neck organs, and the need of the surgical treatment of the thyroid. Stable euthyroidism after the operation led to stable normoglycemia in the patient with previously diagnosed diabetes mellitus type 2. This fact should keep an attention of physicians and endocrinologists to screen for the secondary reasons of hyperglycemia in a patient with diabetes mellitus manifestation. Long-term history of thyrotoxicosis led to the deleterious effects of thyroid hormone excess on the heart (atrial fibrillation, cardiomyopathy, cardiac failure). Those effects are still observed even after thyroidectomy and medical euthyroidism achievement. This fact demonstrates the importance of early diagnosis and treatment of TSH-omas.

Adenoma hipofisário secretor de TSH: uma revisão sistemática / TSH-secreting pituitary adenoma: a systematic review

Introdução: Os adenomas hipofisários são tumores caracterizados pela proliferação de células adeno-hipofisárias produtoras de hormônios tróficos. Dentre eles, os adenomas hipofisários produtores de TSH (TSHomas), neoplasias benignas pouco frequentes, que correspondem a menos do que 3% dos adenomas hipofisários. Método: Pesquisamos os termos TSHomas, tireotropinomas e adenomas pituitários secretores de TSH nas bases Pubmed, Lilacs e Scielo. Incluímos artigos publicados entre 2010 e 2020, sendo excluídos relatos de casos, artigos indisponíveis e que não tratavam sobre o tema. Resultados e discussão: Os TSHomas são tumores fibrosos, monoclonais, com incidência entre 0,015 a 0,03 casos/100.000 habitantes, que se manifestam por hipertireoidismo e sintomas causados por efeito de massa. São diagnosticados diante da elevação de TSH juntamente a hormônios tireoidianos, na presença de alterações neurorradiológicas. O tratamento de primeira escolha consiste na neurocirurgia transesfenoidal, sendo os análogos de somatostatina e a radioterapia alternativas para o manejo de pacientes em que a intervenção cirúrgica é desaconselhada. Conclusão: Os TSHomas são raros, contudo, precisam ser investigados diante da secreção inadequada de TSH.Palavras chave: Adenoma, Hormônios tireoidianos, Neoplasias hipofisárias, Síndrome da secreção inadequada de TSH, Hipertireoidismo centralABSTRACTIntroduction: Pituitary adenomas are tumors characterized by the proliferation of adenohypophysis cells that produce trophic hormones. Among them, TSH-producing pituitary adenomas (TSHomas), uncommon benign neoplasms, whichcorrespond to less than 3% of pituitary adenomas. Method: We searched for the terms TSHomas, thyrotropinomas and pituitary adenomas secreting TSH in the Pubmed, Lilacs and Scielo databases. We included articles published between 2010 and 2020, excluding case reports, articles that were unavailable and did not deal with the topic. Results and discussion: TSHomas are fibrous, monoclonal tumors, with an incidence of 0.015 to 0.03 cases / 100,000 inhabitants, which are manifested by hyperthyroidism and symptoms caused by a mass effect. They are diagnosed with elevated TSH along with thyroid hormones, in the presence of neuroradiological changes. The first-choice treatment consists of transsphenoidal neurosurgery, with somatostatin analogs and radiotherapy being alternatives for the management of patients in whom surgical intervention is not recommended. Conclusion: TSHomas are rare, however, they need to be investigated due to inadequate TSH secretion.Keywords: Adenoma, Thyroid hormones, Pituitary neoplasms, Inappropriate TSH secretion syndrome, Central hypothyroidism

Differential diagnosis between autoimmune thyrotoxicosis and thyroid hormone resistance syndrome: clinical case report

We report a case of 50-year-old woman with thyroid hormone resistance syndrome. For 20 years this patient have been treated for autoimmune thyrotoxicosis: she underwent thyroid surgery and then was on thyroid-blocking therapy. Repeated laboratory tests demonstrated elevated serum thyroid hormones concentrations and elevated TSH concentration. Inappropriate TSH secretion became the reason for conducting further investigations. In those cases, the diagnostic approach is complicated and cases may be referred as a syndrome of thyroid hormones resistance or as a pituitary mass. Results of magnetic resonance imaging as well as results of octreotide test did not confirm TSH-producing pituitary adenoma. Lack of consistent thyrotoxicosis symptoms and normal level of biochemical markers that reflect peripheral tissue response to excessive thyroid hormones action were regarded as an evidence for thyroid hormones resistance syndrome. In cases of thyroid hormone resistance syndrome, there is no reduction in thyroid hormones after octreotide administration and we could observe it in our patient. Thereby clinical data and laboratory tests supported the diagnosis of thyroid hormone resistance syndrome. To establish definitive diagnosis and to verify genetic cause of the disease we performed direct sequencing of the THRB gene exons 910.

DIAGNOSIS OF ENDOCRINE DISEASE: Diagnostic approach to TSH-producing pituitary adenoma

Thyrotropin (TSH)-secreting adenomas (TSHomas) are the rarest form of pituitary adenomas, and most endocrinologists will see few cases in a lifetime, if any. In most cases, the diagnostic approach is complicated and cases may be referred after being presented as a syndrome of inappropriate TSH secretion or as a pituitary mass. This review aims to cover the past, present and possible future diagnostic approaches to TSHomas, including different clinical presentations, laboratory assessment and imaging advances. The differential diagnoses will be discussed, as well as possible coexisting disorders. By evaluating the existing reports and reviews describing this rare condition, this review aims to present a clinically practical suggestion on the diagnosic workup for TSHomas, Major advances and scientific breakthroughs in the imaging area in recent years, facilitating diagnosis of TSHomas, support the belief that future progress within the imaging field will play an important role in providing methods for a more efficient diagnosis of this rare condition.

TSH-secreting pituitary adenoma: benefits of pre-operative octreotide

Summary TSH-secreting pituitary adenomas are rare and the optimal investigation and management is uncertain. We describe a case of a 43 year-old woman with a TSH-secreting pituitary adenoma, highlighting diagnostic testing and our use, pre-operatively of somatostatin analogue therapy, which induced biochemical euthyroidism and a reduction in tumour size. Learning points The differential diagnosis of the syndrome of inappropriate TSH secretion is non-thyroidal illness, medications, assay interference due to heterophilic antibodies, thyroid hormone resistance and TSH-secreting pituitary adenoma. TRH stimulation test and triiodothyronine suppression test assist in differentiating thyroid hormone resistance and TSH-secreting pituitary adenoma. Somatostatin analogue therapy can induce biochemical euthyroidism and reduce tumour size.