Summary

Large-cell neuroendocrine carcinoma (LCNEC) is a rare neuroendocrine prostatic malignancy. It usually arises after androgen deprivation therapy (ADT), while de novo cases are even more infrequent, with only six cases described. The patient was a 78-year-old man with no history of ADT who presented with cervical lymphadenopathy. Diagnostic approaches included PET/CT, MRI, CT scans, ultrasonography, biopsies, and cytological and immunohistochemical evaluations. Results showed a poorly differentiated carcinoma in the thyroid gland accompanied by cervical lymph node enlargement. Thyroid surgery revealed LCNEC metastasis to the thyroid gland. Additional metastases were identified in both the adrenal glands. Despite appropriate treatment, the patient died of the disease. De novo LCNEC of the prostate is a rare, highly aggressive tumor with a poor prognosis. It is resistant to most therapeutic agents, has a high metastatic potential, and is usually diagnosed at an advanced stage. Further studies are required to characterize this tumor.

Learning points

• De novo LCNECs of the prostate gland can metastasize almost anywhere in the body, including the thyroid and adrenal glands.

• LCNECs of the prostate are usually associated with androgen-depriving therapy, but de novo cases are also notable and should be accounted for.

• Further studies are required to fully understand and treat LCNECs more effectively.

Summary

Osilodrostat is a novel, orally administered cortisol synthesis inhibitor, approved in 2020 by the European Medicines Agency (EMA) for the treatment of Cushing’s syndrome in adults. A significant amount of the studies currently available in the literature focus on treatment in patients with Cushing’s disease. However, data collected from patients treated with osilodrostat in real-life settings still represents a small entity. For this reason, in this article, we will discuss two real-life cases of patients with Cushing’s disease treated with this drug. The first report is about a 35-year-old woman with an adrenocorticotrophic hormone (ACTH)-secreting adenoma. After non-curative trans-nasal-sphenoidal (TNS) surgery, due to a small remnant of the adenoma, medical therapy with osilodrostat achieved fast and effective biochemical and clinical response. During treatment, progressive increase of ACTH levels and an enlargement of the pituitary remnant were documented, with planned radiosurgical treatment. The second case reports a 32-year-old man diagnosed with Cushing’s disease in 2020, who, after surgery refusal, started osilodrostat at progressively up-titrated doses, according to 24 h urinary free cortisol levels, up to 5 mg twice a day. With osilodrostat, the patient reached biochemical and clinical control of disease until TNS surgery in October 2021, with complete remission. The first post-surgical biochemical assessment was equivocal in spite of a transient clinical hypoadrenalism, reverted after 2 months with the restoration of physiological hypothalamic-pituitary-adrenal axis (HPA) function.

Learning points

• Osilodrostat is a potent oral drug viable for Cushing’s disease as medical therapy when surgery is not feasible or remission cannot be reached.

• Osilodrostat proves to be a safe drug and its main adverse effect is hypoadrenalism, due to the adrenolytic action of the compound.

• Osilodrostat needs a very tailored approach in its clinical use because there is no correlation between the level of hypercortisolism pre-treatment and the dose required to reach disease control.

Summary

Complicated Rathke’s cleft cyst (RCC) is a rare occurrence of symptomatic bleeding or growth of a previously asymptomatic (and often undiagnosed) intrasellar cyst derived from remnants of Rathke’s pouch, situated on the midline between the adeno- and neurohypophysis. Symptoms may be identical to those of pituitary apoplexy: acute onset of headache, hypopituitarism, and neurological disturbances. Both syndromes may also exhibit a similar appearance of a large haemorrhagic sellar mass at initial radiological evaluation. We report on two patients who presented with headache and complete hypopituitarism. Based on the initial MRI, they were first diagnosed with pituitary apoplexy but managed conservatively with hormone therapy alone because of the absence of severe visual or neurological threat. Upon follow-up at 4 months, clinical evolution was good in both patients but their pituitary mass had not reduced in size and, after careful radiologic reviewing, was more indicative of a large midline complicated RCC. In conclusion, the diagnosis of complicated RCC is challenging because it can mimic pituitary apoplexy clinically, biologically, and radiologically. Clinicians should distinguish between the two entities using specific radiological signs or evolution of the mass at MRI if the patient does not undergo surgery. To our knowledge, we report conservative management of this rare condition for the first time, though it seems appropriate in the absence of neurological compromise or visual compression. Long-term follow-up is however mandatory.

Learning points

• Complicated Rathke’s cleft cyst can mimic pituitary apoplexy, presenting with sudden onset of headache, hypopituitarism, and visual and neurological compromise in the most severe cases.

• At diagnosis, pituitary MRI may not be able to differentiate between the two entities, showing a large haemorrhagic mass inside the sella, with little or no normal pituitary tissue visible. Patients are often diagnosed with apoplexy at this stage and may undergo pituitary surgery.

• When surgery has not been performed initially in these patients, repeat imaging at 3–6 months is unchanged and does not show the expected involution usually seen after adenoma apoplexy.

• Conservative management with hormonal replacement seems a valid option in the absence of visual or neurological deficits that would require trans-sphenoidal surgery.

Summary

Leptin is secreted by adipocytes in response to fat storage and binds to its receptor (LEPR), which is ubiquitously expressed throughout the body. Leptin regulates energy expenditure and is anorexigenic. In this study, we describe the clinical and hormonal findings of three siblings with a personal history of rapid weight gain during the first months of life. They had delayed puberty, high levels of FSH (15.6 ± 3.7 mUI/mL; reference: 1.5–12.4) and LH (12.3 ± 2.2 mUI/mL; reference: 1.7–8.6), normal oestradiol and total testosterone and successful fertility. None of the patients had dyslipidemia, diabetes or thyroid disease. Next-generation sequencing identified a pathogenic homozygous variant c.2357T>C, p.(Leu786Pro) in LEPR. Their parents and children were heterozygous for this mutation. We compared clinical and biochemical findings of homozygous carriers with first-degree heterozygous family members and ten randomly selected patients with adult-onset morbid obesity. Homozygous carriers of the mutation had significantly higher BMI (32.2 ± 1.7 kg/m² vs 44.5 ± 7.1 kg/m², P = 0.023) and increased serum levels of leptin (26.3 ± 9.3 ng/mL vs 80 ± 36.4 ng/mL, P = 0.028) than their heterozygous relatives. Compared with the ten patients with adult-onset morbid obesity, serum levels of leptin were not significantly higher in homozygous carriers (53.8 ± 24.1 ng/mL vs 80 ± 36.4 ng/mL, P = 0.149), and thus serum levels of leptin were not a useful discriminative marker of LEPR mutations. We described a rare three-generation family with monogenic obesity due to a mutation in LEPR. Patients with early onset obesity should be considered for genetic screening, as the identification of mutations may allow personalized treatment options (e.g. MC4R-agonists) and targeted successful weight loss.

Learning points

• The early diagnosis of monogenic forms of obesity can be of great interest since new treatments for these conditions are becoming available.

• Since BMI and leptin levels in patients with leptin receptor mutations are not significantly different from those found in randomly selected morbid obese patients, a careful medical history is mandatory to suspect this condition.

• Loss of leptin receptor function has been associated with infertility. However, our patients were able to conceive, emphasizing the need for genetic counselling in affected patients with this condition.

Summary

Vasoactive intestinal peptide-secreting tumours (VIPomas) are an extremely rare form of functional pancreatic neuroendocrine tumour with an estimated annual incidence of 1 in 10 million. Associated tumour hypersecretion of other peptides, including pancreatic polypeptide (PPomas), may also be seen. These malignancies classically present with a defined triad of refractory diarrhoea, hypokalaemia and metabolic acidosis known as Verner–Morrison syndrome. Diagnosis is frequently delayed, and the majority of patients will have metastatic disease at presentation. Symptoms are usually well controlled with somatostatin analogue administration. Here we report a case of metastatic mixed VIPoma/PPoma-induced diarrhoea causing renal failure so severe that ultrafiltration was required to recover adequate renal function.

Learning points

• Profuse, watery diarrhoea is a common presenting complaint with a multitude of aetiologies. This, combined with the rarity of these tumours, makes diagnosis difficult and frequently delayed. A functional neuroendocrine tumour should be suspected when diarrhoea is unusually extreme, prolonged and common causes have been promptly excluded.

• These patients are likely to be profoundly unwell on presentation. They are extremely hypovolaemic with dangerous electrolyte and metabolic abnormalities. Aggressive initial rehydration and electrolyte replacement are imperative. A somatostatin analogue should be commenced as soon as the diagnosis is suspected.

• This is an extreme example of Verner–Morrison syndrome. We are unaware of another case where renal failure secondary to diarrhoea and dehydration was so severe that renal replacement therapy was required to restore adequate renal function, further emphasising how critically unwell these patients can be.

• Both the primary tumour and metastases showed a remarkably good and rapid response to somatostatin analogue administration. Cystic change and involution were noted on repeat imaging within days.

• Prior to his illness, this patient was extremely high functioning with no medical history. His diagnosis was an enormous psychological shock, and the consideration and care for his psychological well-being were a crucial part of his overall management. It highlights the importance of a holistic approach to cancer care and the role of the clinical nurse specialist within the cancer multidisciplinary team.

Summary

Gorham–Stout disease (GSD) is a rare bone disease characterized by massive osteolysis and lymphatic proliferation. The origin of the condition is unknown, and no established treatment protocol exists. Massive pleural effusion is a frequent complication of GSD in the thoracic region. We present the case of a 23-year-old male with thoracic GSD, subsequent paraparesis, and life-threatening pleural effusion. The patient was managed by a multidisciplinary team with a good recovery. The pleural effusion was successfully treated with a pleuro-peritoneal shunt. This is the first report of the use of this mini-invasive technique in the management of pleural effusion related to GSD. Further, we present the potential role of interleukin-6 and bone resorption markers in the measurement of the disease activity.

Learning points

• Multidisciplinary approach is important in the management of rare and severe disorders such as Gorham-Stout disease.

• Pleuro-peritoneal shunting is a valuable option in the treatment of pleural effusion related to GSD.

• Interleukin-6 and bone resorption markers appear useful in measuring the disease activity of GSD.

Summary

Insulinomas are a rare cause of persistent hypoglycemia in a previously healthy child. In addition to symptoms of hypoglycemia, individuals with insulinomas usually present with a history of incessant caloric intake and weight gain due to a constant need to counter hypoglycemia. In addition to an extensive review of the literature, we report the first case of an insulinoma coexisting with reduced appetite secondary to anorexia nervosa in an adolescent female.

Learning points

• Eliciting a detailed family history is important in hypoglycemia cases.

• Obtaining a thorough dietary intake, weight history, and menstrual cycles (in females) and considering a psychiatric consultation for an eating disorder when indicated.

• Although rare in the pediatric population, multiple endocrine neoplasia type 1 syndrome should be considered in the evaluation of children and adolescents with hypoglycemia who also have a family history of pituitary, pancreatic, and/or parathyroid endocrinopathies.

Summary

A 49-year-old teacher presented to his general physician with lethargy and lower limb weakness. He had noticed polydipsia, polyuria, and had experienced weight loss, albeit with an increase in central adiposity. He had no concomitant illnesses and took no regular medications. He had hypercalcaemia (adjusted calcium: 3.34 mmol/L) with hyperparathyroidism (parathyroid hormone: 356 ng/L) and hypokalaemia (K: 2.7 mmol/L) and was admitted for i.v. potassium replacement. A contrast-enhanced CT chest/abdomen/pelvis scan revealed a well-encapsulated anterior mediastinal mass measuring 17 × 11 cm with central necrosis, compressing rather than invading adjacent structures. A neck ultrasound revealed a 2 cm right inferior parathyroid lesion. On review of CT imaging, the adrenals appeared normal, but a pancreatic lesion was noted adjacent to the uncinate process. His serum cortisol was 2612 nmol/L, and adrenocorticotrophic hormone was elevated at 67 ng/L, followed by inadequate cortisol suppression to 575 nmol/L from an overnight dexamethasone suppression test. His pituitary MRI was normal, with unremarkable remaining anterior pituitary biochemistry. His admission was further complicated by increased urine output to 10 L/24 h and despite three precipitating factors for the development of diabetes insipidus including hypercalcaemia, hypokalaemia, and hypercortisolaemia, due to academic interest, a water deprivation test was conducted. An ¹⁸flurodeoxyglucose-PET (FDG-PET) scan demonstrated high avidity of the mediastinal mass with additionally active bilateral superior mediastinal nodes. The pancreatic lesion was not FDG avid. On 68Ga DOTATE-PET scan, the mediastinal mass was moderately avid, and the 32 mm pancreatic uncinate process mass showed significant uptake. Genetic testing confirmed multiple endocrine neoplasia type 1.

Learning points

• In young patients presenting with primary hyperparathyroidism, clinicians should be alerted to the possibility of other underlying endocrinopathies.

  In patients with multiple endocrine neoplasia type 1 (MEN-1) and ectopic adrenocorticotrophic hormone syndrome (EAS), clinicians should be alerted to the possibility of this originating from a neoplasm above or below the diaphragm.

• Although relatively rare compared with sporadic cases, thymic carcinoids secondary to MEN-1 may also be associated with EAS.

• Electrolyte derangement, in particular hypokalaemia and hypercalcaemia, can precipitate mild nephrogenic diabetes insipidus.

Summary

Maturity-onset diabetes of the young type 3 (MODY3) accounts for approximately 50% of cases of MODY. First-line treatment with sulfonylureas has been well established for individuals with MODY3. In contrast, the use of sodium-glucose co-transporter 2 (SGLT2) inhibitors in the treatment of individuals with MODY3 remains unclear. This case illustrates the in vivo effect of an SGLT2 inhibitor in a 30-year-old woman with MODY3 with poor glycaemic control despite the treatment with supramaximal doses of sulfonylurea and metformin. The addition of a SGLT2 inhibitor resulted in a rapid improvement in glycaemic control without any hypoglycaemic episodes. This case suggests that SGLT2 inhibitors may be an effective and potent treatment option in addition to sulfonylureas for individuals with MODY3.

Learning points

• Maturity-onset diabetes of the young type 3 (MODY3) arises from mutations in the hepatocyte nuclear factor-1alpha gene, which controls the expression of sodium-glucose co-transporter 2 (SGLT2) in the kidneys.

• Paradoxically, despite individuals with MODY3 having reduced expression of SGLT2, SGLT2 inhibitors induce higher glycosuria in individuals with MODY3 compared to individuals with type 2 diabetes mellitus.

• SGLT2 inhibitors may be an effective treatment for achieving glycaemic control in individuals with MODY3.

Summary

Feminizing estrogen-secreting adrenocortical carcinomas (ACCs) are exceedingly rare and carry a poor prognosis. The most common presenting trait is gynecomastia, but enlarged breasts are also a frequent clinical finding in healthy men. Biochemical evaluation may be challenging. As such, there is a high risk of delayed diagnosis and treatment opportunity. Here, we present a case with an estrogen-producing ACC where the abnormal steroid profile obtained at the time of initial workup was essential for the prompt diagnosis. Wider adoption of liquid chromatography mass spectrometry-based steroid assays has potential to improve early diagnosis of feminizing estrogen-secreting ACC.

Learning points

• Feminizing estrogen-secreting adrenocortical carcinomas (ACCs) are a rare, but an important differential diagnosis in men with rapidly developing gynecomastia.

• Biochemical evaluation is essential for a prompt diagnosis.

• Steroid hormone profiling using liquid chromatography mass spectrometry technology has the potential to improve early diagnosis of feminizing estrogen-secreting ACC.