Browse
Search for other papers by Jenny S W Yun in
Google Scholar
PubMed
Search for other papers by Chris McCormack in
Google Scholar
PubMed
Search for other papers by Michelle Goh in
Google Scholar
PubMed
University of Melbourne, Parkville, Victoria, Australia
Search for other papers by Cherie Chiang in
Google Scholar
PubMed
Summary
Acanthosis nigricans (AN) is a common dermatosis associated with hyperinsulinemia and insulin resistance. However, AN has been rarely reported in patients with insulinoma, a state of persistent hyperinsulinemia. We present a case of metastatic insulinoma, in whom AN manifested after the first cycle of peptide receptor radionuclide therapy (PRRT). A 40-year-old man was diagnosed with metastatic insulinoma after 5 months of symptomatic hypoglycemia. Within 1 month post PRRT, the patient became euglycemic but developed a pigmented, pruritic rash which was confirmed on biopsy as AN. We discuss the rare manifestation of AN in subjects with insulinoma, the role of insulin in the pathogenesis of AN, malignant AN in non-insulin-secreting malignancies and association with other insulin-resistant endocrinopathies such as acromegaly.
Learning points
-
Acanthosis nigricans (AN) is a common dermatosis which is typically asymptomatic and associated with the hyperinsulinemic state.
-
Malignant AN can rapidly spread, cause pruritus and affect mucosa and the oral cavity.
-
AN is extremely rare in patients with insulinoma despite marked hyperinsulinemia.
-
Peptide receptor radionuclide therapy might have triggered TGF-α secretion in this subject which led to malignant AN.
-
Rapid spread or unusual distribution of pruritic AN warrants further investigation to exclude underlying malignancy.
Department of Medicine, University College London, London, UK
Search for other papers by Ziad Hussein in
Google Scholar
PubMed
Search for other papers by Marta Korbonits in
Google Scholar
PubMed
Department of Medicine, University College London, London, UK
Search for other papers by Stephanie E Baldeweg in
Google Scholar
PubMed
Search for other papers by Teng-Teng Chung in
Google Scholar
PubMed
Summary
We observed a novel therapeutic response with cabergoline in a male patient with a dopamine-secreting head and neck paraganglioma (HNPGL), macroprolactinoma and germline succinate dehydrogenase C mutation (SDHC). The macroprolactinoma was treated with cabergoline which gave an excellent response. He was found to have raised plasma 3-methoxytyramine of 1014 pmol/L (NR: 0–180 pmol/L); but it was unclear if this was a drug-induced phenomenon from dopamine agonist (DA) therapy. Cabergoline was stopped for 4 weeks and the 3-methoxytyramine level increased significantly to 2185 pmol/L, suggesting a biochemical response of his HNPGL. Subsequently, Gallium-68 Dotatate PET and MRI (Gallium-68 Dotatate PET/MRI) demonstrated a second lesion in the sacrum. Both the HNPGL and metastatic sacral deposit received external beam radiotherapy with a good biochemical and radiological response.
Conclusion
Our case report highlights the rare potential of germline SDHC mutations causing metastatic paraganglioma and concurrent pituitary tumours. Cabergoline treatment may lower elevated 3-methoxytyramine levels and, therefore, mask the biochemical evidence of metastatic disease but also may have therapeutic relevance in dopamine-secreting pheochromocytomas/paragangliomas (PPGLs).
Learning points
-
Several neuroendocrine tumours (NETs) express dopamine D2 and D4 receptors. In this case report, cabergoline significantly reduced plasma 3-methoxytyramine level in a patient with functional HNPGL. Cabergoline might have therapeutic relevance in dopamine-secreting PPGLs.
-
Paragangliomas associated with SDHC mutation classically present with asymptomatic non-functional HNPGL and have rare metastatic potential.
-
The association of pheochromocytoma or paraganglioma and pituitary adenoma is now a well-described rare association (<1%), designated as the three P association. While the three P association is most commonly seen with succinate dehydrogenase B and D mutations, it has also been described in patients with SDHA and SDHC mutations.
-
Cabergoline treatment may lower elevated 3-methoxytyramine levels and mask the biochemical evidence of metastatic disease. Regular functional imaging with Gallium-68 Dotatate PET/MRI provides better evidence of metastatic disease.
Department of Radiology, Hanoi Medical University, Hanoi, Vietnam
Search for other papers by Le Tuan Linh in
Google Scholar
PubMed
Department of Radiology, Childrent’s Hospital 2, Ho Chi Minh city, Vietnam
Search for other papers by Nguyen Minh Duc in
Google Scholar
PubMed
Search for other papers by Hoang Tu Minh in
Google Scholar
PubMed
Search for other papers by Nguyen Ngoc Cuong in
Google Scholar
PubMed
Search for other papers by Vuong Thu Ha in
Google Scholar
PubMed
Search for other papers by Dao-Thi Luan in
Google Scholar
PubMed
Search for other papers by Thieu-Thi Tra My in
Google Scholar
PubMed
Department of Radiology, Hanoi Medical University, Hanoi, Vietnam
Search for other papers by Bui Van Lenh in
Google Scholar
PubMed
Summary
Primary hepatic neuroendocrine tumor (PHNET) is a rare type of neuroendocrine tumor (NET) that is also a primary hepatic tumor. Patients are present with almost no specific clinical symptoms and typically present with negative test results and atypical imaging characteristics; therefore, the differentiation of PHNET from other types of primary hepatic masses can be very difficult. In this article, we describe a case of PHNET that mimicked a liver helminth infection in a 57-year-old man. The diagnosis of PHNET in this patient was challenging, and the final diagnosis was based on imaging, histopathology features, and long-term follow-up.
Learning points
-
An uncommon type of neuroendocrine tumor (NET) is a primary hepatic neuroendocrine tumor (PHNET).
-
Primary hepatic neuroendocrine tumors are rare NET lesions found in the liver, characterized by non-specific clinical and imaging results, which can be easily confused with other liver lesions, including HCC and parasitic lesions.
-
To have a conclusive diagnosis and classification, a mixture of many medical assessment techniques, such as imaging, gastrointestinal endoscopy, nuclear medicine, anatomy, including histopathology, and immunohistochemistry, is essential.
Search for other papers by Ziadoon Faisal in
Google Scholar
PubMed
Search for other papers by Miguel Debono in
Google Scholar
PubMed
Summary
In this case report, we describe the management of a patient who was admitted with an ectopic ACTH syndrome during the COVID pandemic with new-onset type 2 diabetes, neutrophilia and unexplained hypokalaemia. These three findings when combined should alert physicians to the potential presence of Cushing’s syndrome (CS). On admission, a quick diagnosis of CS was made based on clinical and biochemical features and the patient was treated urgently using high dose oral metyrapone thus allowing delays in surgery and rapidly improving the patient’s clinical condition. This resulted in the treatment of hyperglycaemia, hypokalaemia and hypertension reducing cardiovascular risk and likely risk for infection. Observing COVID-19 pandemic international guidelines to treat patients with CS has shown to be effective and offers endocrinologists an option to manage these patients adequately in difficult times.
Learning points
-
This case report highlights the importance of having a low threshold for suspicion and investigation for Cushing’s syndrome in a patient with neutrophilia and hypokalaemia, recently diagnosed with type 2 diabetes especially in someone with catabolic features of the disease irrespective of losing weight.
-
It also supports the use of alternative methods of approaching the diagnosis and treatment of Cushing’s syndrome during a pandemic as indicated by international protocols designed specifically for managing this condition during Covid-19.
Search for other papers by Joana Lima Ferreira in
Google Scholar
PubMed
Search for other papers by Bernardo Marques in
Google Scholar
PubMed
Search for other papers by C Willemien Menke-van der Houven van Oordt in
Google Scholar
PubMed
Search for other papers by Wouter W de Herder in
Google Scholar
PubMed
Search for other papers by Tessa Brabander in
Google Scholar
PubMed
Search for other papers by Johannes Hofland in
Google Scholar
PubMed
Summary
Middle ear adenomas with neuroendocrine features (ANEF) are rare, with an estimated 150 reported cases. They usually pursue an indolent clinical course. Four reported cases of middle ear ANEF with distant metastases were treated with surgery, external beam radiation therapy (EBRT) and chemotherapy. To date, no successful systemic treatment for malignant behaviour of this rare tumour has been reported. Long-acting somatostatin analogues (SSAs) and peptide receptor radionuclide therapy (PRRT) have been used in well-differentiated metastatic neuroendocrine tumours (NETs), but their use has never been described in cases of metastatic middle ear ANEF. We report two patients with grade 1 middle ear ANEF treated with surgery and EBRT. They had stable disease for several years, until clinical symptoms appeared and extensive metastases were detected on 68Ga-DOTA0-Tyr3-octreotate (DOTATATE) PET/CT. Treatment with long-acting SSA was started, with stable disease for 1 year. Afterwards, despite undergoing local treatments, both patients presented progressive disease. Due to high-uptake metastases at 68Ga-DOTATATE PET/CT, both cases underwent four cycles of PRRT with 177Lu-DOTATATE, which secured disease control and improvement of quality of life in both. Similar to other well-differentiated NETs, SSA and PRRT could constitute efficacious therapeutic options in metastatic middle ear ANEF. Its neuroendocrine differentiation, potential to metastasize and somatostatin receptor type 2 expression prompt consideration and management of this disease as a neuroendocrine neoplasm.
Learning points
-
Our cases oppose the 2017 WHO classification of middle ear adenoma with neuroendocrine features as a benign disease.
-
This entity warrants long-term follow-up, as local recurrence or persistence of disease is reported in up to 18% of surgically treated patients.
-
PET/CT scan with 68Ga-labelled somatostatin analogues (SSA) can be used for staging of metastatic middle ear adenoma with neuroendocrine features.
-
Unlabelled SSA and peptide receptor radionuclide therapy (PRRT) with radiolabelled SSA can be the first systemic therapeutic options for patients with advanced middle ear adenoma with neuroendocrine features.
Search for other papers by Sarah Y Qian in
Google Scholar
PubMed
Search for other papers by Matthew J L Hare in
Google Scholar
PubMed
Search for other papers by Alan Pham in
Google Scholar
PubMed
Department of Medicine, Monash University, Melbourne, Australia
Search for other papers by Duncan J Topliss in
Google Scholar
PubMed
Summary
Insulinomas are rare neuroendocrine tumours that classically present with fasting hypoglycaemia. This case report discusses an uncommon and challenging case of insulinoma soon after upper gastrointestinal surgery. A 63-year-old man presented with 6 months of post-prandial hypoglycaemia beginning after a laparoscopic revision of Toupet fundoplication. Hyperinsulinaemic hypoglycaemia was confirmed during a spontaneous episode and in a mixed-meal test. Localisation studies including magnetic resonance imaging (MRI), endoscopic ultrasound (EUS) and gallium dotatate positron emission tomography (68Ga Dotatate PET) were consistent with a small insulinoma in the mid-body of the pancreas. The lesion was excised and histopathology was confirmed a localised well-differentiated neuroendocrine pancreatic neoplasm. There have been no significant episodes of hypoglycaemia since. This case highlights several key points. Insulinoma should be sought in proven post-prandial hyperinsulinaemic hypoglycaemia – even in the absence of fasting hypoglycaemia. The use of nuclear imaging targeting somatostatin and GLP1 receptors has improved accuracy of localisation. Despite these advances, accurate surgical resection can remain challenging.
Learning points:
-
Hypoglycaemia is defined by Whipple’s triad and can be provoked by fasting or mixed-meal tests.
-
Although uncommon, insulinomas can present with post-prandial hypoglycaemia.
-
In hypoglycaemia following gastrointestinal surgery (i.e. bariatric surgery or less commonly Nissen fundoplication) dumping syndrome or non-insulinoma pancreatogenous hypoglycaemia syndrome (NIPHS) should be considered.
-
Improved imaging techniques including MRI, endoscopic ultrasound and functional nuclear medicine scans aid localisation of insulinomas.
-
Despite advances in imaging and surgical techniques, accurate resection of insulinomas remains challenging.
Search for other papers by Rowena Speak in
Google Scholar
PubMed
Search for other papers by Jackie Cook in
Google Scholar
PubMed
Search for other papers by Barney Harrison in
Google Scholar
PubMed
Endocrinology
Search for other papers by John Newell-Price in
Google Scholar
PubMed
Mutations of the rearranged during transfection (RET) proto-oncogene, located on chromosome 10q11.2, cause multiple endocrine neoplasia type 2A (MEN2A). Patients with mutations at the codon 609 usually exhibit a high penetrance of medullary thyroid cancer (MTC), but a sufficiently low penetrance of phaeochromocytoma that screening for this latter complication has been called to question. Patients with other RET mutations are at higher risk of younger age onset phaeochromocytoma if they also possess other RET polymorphisms (L769L, S836S, G691S and S904S), but there are no similar data for patients with 609 mutations. We investigated the unusual phenotypic presentation in a family with MEN2A due to a C609Y mutation in RET. Sanger sequencing of the entire RET-coding region and exon–intron boundaries was performed. Five family members were C609Y mutation positive: 3/5 initially presented with phaeochromocytoma, but only 1/5 had MTC. The index case aged 73 years had no evidence of MTC, but presented with phaeochromocytoma. Family members also possessed the G691S and S904S RET polymorphisms. We illustrate a high penetrance of phaeochromocytoma and low penetrance of MTC in patients with a RET C609Y mutation and polymorphisms G691S and S904S. These data highlight the need for life-long screening for the complications of MEN2A in these patients and support the role for the screening of RET polymorphisms for the purposes of risk stratification.
Learning points:
-
C609Y RET mutations may be associated with a life-long risk of phaeochromocytoma indicating the importance of life-long screening for this condition in patients with MEN2A.
-
C609Y RET mutations may be associated with a lower risk of MTC than often quoted, questioning the need for early prophylactic thyroid surgery discussion at the age of 5 years.
-
There may be a role for the routine screening of RET polymorphisms, and this is greatly facilitated by the increasing ease of access to next-generation sequencing.
Wolfson Diabetes and Endocrinology Clinic, Institute of Metabolic Science, Cambridge University Hospitals NHS Foundation Trust, Addenbrookes Hospital, Box 281, Cambridge, CB2 0QQ, UK
Search for other papers by Benjamin G Challis in
Google Scholar
PubMed
Faculty of Health and Medical Sciences, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Blegdamsvej 3B, Copenhagen, DK-2200, Denmark
Search for other papers by Nicolai J Wewer Albrechtsen in
Google Scholar
PubMed
Search for other papers by Vishakha Bansiya in
Google Scholar
PubMed
Search for other papers by Keith Burling in
Google Scholar
PubMed
Search for other papers by Peter Barker in
Google Scholar
PubMed
Faculty of Health and Medical Sciences, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Blegdamsvej 3B, Copenhagen, DK-2200, Denmark
Search for other papers by Bolette Hartmann in
Google Scholar
PubMed
Search for other papers by Fiona Gribble in
Google Scholar
PubMed
Wolfson Diabetes and Endocrinology Clinic, Institute of Metabolic Science, Cambridge University Hospitals NHS Foundation Trust, Addenbrookes Hospital, Box 281, Cambridge, CB2 0QQ, UK
Search for other papers by Stephen O'Rahilly in
Google Scholar
PubMed
Faculty of Health and Medical Sciences, Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Blegdamsvej 3B, Copenhagen, DK-2200, Denmark
Search for other papers by Jens J Holst in
Google Scholar
PubMed
Search for other papers by Helen L Simpson in
Google Scholar
PubMed
Summary
Pancreatic neuroendocrine tumours (pNETs) secreting proglucagon are associated with phenotypic heterogeneity. Here, we describe two patients with pNETs and varied clinical phenotypes due to differential processing and secretion of proglucagon-derived peptides (PGDPs). Case 1, a 57-year-old woman presented with necrolytic migratory erythema, anorexia, constipation and hyperinsulinaemic hypoglycaemia. She was found to have a grade 1 pNET, small bowel mucosal thickening and hyperglucagonaemia. Somatostatin analogue (SSA) therapy improved appetite, abolished hypoglycaemia and improved the rash. Case 2, a 48-year-old male presented with diabetes mellitus, diarrhoea, weight loss, nausea, vomiting and perineal rash due to a grade 1 metastatic pNET and hyperglucagonaemia. In both cases, plasma levels of all measured PGDPs were elevated and attenuated following SSA therapy. In case 1, there was increased production of intact glucagon-like peptide 1 (GLP-1) and GLP-2, similar to that of the enteroendocrine L cell. In case 2, pancreatic glucagon was elevated due to a pancreatic α-cell-like proglucagon processing profile. In summary, we describe two patients with pNETs and heterogeneous clinical phenotypes due to differential processing and secretion of PGDPs. This is the first description of a patient with symptomatic hyperinsulinaemic hypoglycaemia and marked gastrointestinal dysfunction due to, in part, a proglucagon-expressing pNET.
Learning points
-
PGDPs exhibit a diverse range of biological activities including critical roles in glucose and amino acid metabolism, energy homeostasis and gastrointestinal physiology.
-
The clinical manifestations of proglucagon-expressing tumours may exhibit marked phenotypic variation due to the biochemical heterogeneity of their secreted peptide repertoire.
-
Specific and precise biochemical assessment of individuals with proglucagon-expressing tumours may provide opportunities for improved diagnosis and clinical management.
