Management of hypopituitarism: a perspective from the Brazilian Society of Endocrinology and Metabolism

TTF1-positive posterior pituitary tumors: a single-center experience of 10 years

PURPOSE

Primary TTF1-positive posterior pituitary tumors (PPT) are uncommon and frequently misdiagnosed preoperatively. This study aims to describe our experience with PPT, examining clinical, radiological and histopathological data, as well as surgical and clinical outcomes.

METHODS

We conducted a retrospective review of medical records from patients treated at a single neurosurgical center between 2013 and 2023. Immunohistochemistry for TTF-1 was performed using AB_1158934.

RESULTS

Nine PPT were included: 6 spindle cell oncocytomas (SCO), 2 granular cell tumor (GCT) and 1 pituicytoma. The median age was 53 years (range 34-70), with six (66.7%) patients being male. Most patients presented preoperatively with panhypopituitarism (8 cases), visual impairment (7 cases) and headache (7 cases). The median largest tumor diameter of 2.7 cm (range 1.7-5.4 cm) and PPT appeared isointense on T1W. SCO typically manifested as large intrasellar tumors with suprasellar extension and pronounced contrast-enhancement. GCT and pituicytoma were predominantly suprasellar lesions, with GCT showing a characteristic "star-like crack" pattern. Surgical outcomes varied, with the minority of successful cases involving SCO, known for their hypervascularity and firm consistency.

CONCLUSION

PTT constituted 0.6% of sellar/suprasellar surgeries at our center. SCO should be suspected if a large and significant contrast-enhancement lesion is seen, and GCT if there is a suprasellar tumor with a "star-like crack" pattern. Surgical outcomes were not favorable: the majority of cases showed subtotal resection requiring adjuvant radiotherapy. Long-term follow-up is crucial due to the limited curative outcomes observed in most patients.

Hypopituitarism presenting with cardiovascular manifestations: a case report

Hypopituitarism is a rare condition that can be particularly challenging to diagnose in individuals aged 65 and older. It is characterized by a reduced production of one or more hormones by the pituitary gland, resulting in a deficiency of the hormones that normally regulate various bodily functions. While hypopituitarism can affect multiple systems in the body, it is uncommon for it to present with cardiovascular symptoms. This rarity often leads to the condition being overlooked in clinical practice. Therefore, healthcare professionals must maintain a high level of suspicion for hypopituitarism to ensure timely diagnosis and appropriate management. In this study, we present a case of hypopituitarism caused by a tumor in the sellar region, which uniquely manifested with cardiovascular symptoms.

Altered amino acid levels in young hypopituitarism: impact of NAFLD and insulin resistance

Elevated concentrations of amino acids (AAs) are commonly observed in patients with nonalcoholic fatty liver disease (NAFLD). Individuals with hypopituitarism (HP) are at a heightened risk of developing NAFLD due to factors such as visceral obesity, increased insulin resistance (IR), and disturbances in lipid metabolism. However, the changes in AAs concentrations associated with HP remain poorly understood. Therefore, our study aimed to investigate whether individuals with HP, who were not receiving growth hormone replacement therapy (GHRT), exhibited altered AAs compared to controls (CTs), and whether these AAs were associated with IR, the presence of NAFLD, and the Metabolic Syndrome (MetS) score. The AAs profiles of 133 young males with HP (age: 24.5 ± 5.9; 57 with NAFLD and 76 without NAFLD) and 90 age and BMI-matched CTs were analyzed using untargeted metabolomics. The results revealed that most AAs were found to be elevated in subjects with HPs compared to CTs. Glutamate, glutamine, norleucine, and branched-chain amino acids (BCAAs) (leucine and valine) were correlated with the homeostasis model assessment of insulin resistance (HOMA-IR), with glutamate and norleucine showing independent linkage. Glutamate and proline levels were specifically associated with MetS score, while alanine and proline linked to NAFLD. Given that elevated glutamate and BCAAs levels have higher prevalence of NAFLD, we hypothesized that the changes in AAs observed in HPs may be attributed to the impact of NAFLD and IR.

Progress, challenges and perspectives in the management of hypopituitarism

Hypopituitarism is a rare endocrine disorder characterized by insufficient hormone secretion from the pituitary gland. This condition leads to deficient production of one or more pituitary hormones, including growth hormone (GH), thyroid-stimulating hormone (TSH), luteinizing hormone (LH), follicle-stimulating hormone (FSH), adrenocorticotropic hormone (ACTH), and antidiuretic hormone (ADH), also called arginine vasopressin (AVP). Symptoms vary widely and are often not, late recognized.Diagnosis typically involves a thorough clinical evaluation, hormone level assessments, and neuroimaging studies to identify underlying causes. Treatment aims to replace deficient hormones and address the underlying cause and related complications when possible. In this special issue we address diagnosis, comorbidities, and management of hypopituitarism. We hope that it will help healthcare professionals to manage their patients.

Special features on insulin resistance, metabolic syndrome and vascular complications in hypopituitary patients

Pituitary hormone deficiency, hypopituitarism, is a dysfunction resulting from numerous etiologies, which can be complete or partial, and is therefore heterogeneous. This heterogeneity makes it difficult to interpret the results of scientific studies with these patients.Adequate treatment of etiologies and up-to-date hormone replacement have improved morbidity and mortality rates in patients with hypopituitarism. As GH replacement is not performed in a reasonable proportion of patients, especially in some countries, it is essential to understand the known consequences of GH replacement in each subgroup of patients with this heterogeneous dysfunction.In this review on hypopituitarism, we will address some particularities regarding insulin resistance, which is no longer common in these patients with hormone replacement therapy based on current guidelines, metabolic syndrome and its relationship with changes in BMI and body composition, and to vascular complications that need to be prevented taking into account the individual characteristics of each case to reduce mortality rates in these patients.

Subclinical central hypothyroidism in patients with hypothalamic-pituitary disease: does it exist?

Central hypothyroidism (CH) is characterized by decreased thyroid hormone production due to insufficient stimulation of an otherwise normal thyroid gland by TSH. In patients with established hypothalamic-pituitary disease, a low FT4 concentration is considered highly specific, although poorly sensitive, for the diagnosis of CH. That would be comparable to diagnosing primary hypothyroidism in patients at risk only when serum FT4 concentrations are below the reference range, missing all patients with subclinical primary hypothyroidism and preventing proper therapy in patients in which thyroxine replacement is clearly beneficial. Cardiac time intervals, especially the isovolumic contraction time (ICT), have been considered the gold standard of peripheral thyroid hormone action. Using Doppler echocardiography, we have previously shown a very high proportion of prolonged ICT in patients with hypothalamic-pituitary disease and serum FT4 levels indistinguishable from controls. As ICT decreased/normalized after thyroxine-induced increases in FT4 concentrations within the normal reference range, prolonged ICT was considered a bona fide diagnostic biomarker of subclinical CH. Those findings challenge the usual interpretation that FT4 concentrations in the mid-reference range exclude hypothyroidism in patients with hypothalamic-pituitary disease. Rather, subclinical central hypothyroidism, a state analogous to subclinical primary hypothyroidism, seems to be frequent in patients with hypothalamic-pituitary disease and normal FT4 levels. They also challenge the notion that thyroid function is usually the least or the last affected in acquired hypopituitarism. The relevance of Doppler echocardiography to correctly diagnose and monitor replacement therapy in both clinical and subclinical forms of CH should improve quality of life and decrease cardiovascular risk, as already demonstrated in patients with clinical and subclinical primary hypothyroidism.