Diagnosis and Treatment > Signs and Symptoms
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.
School of Medicine and Dentistry, James Cook University, Douglas, Queensland, Australia
Search for other papers by Beverly T Rodrigues in
Google Scholar
PubMed
Search for other papers by Zulfiquer Otty in
Google Scholar
PubMed
Search for other papers by Kunwarjit Sangla in
Google Scholar
PubMed
School of Medicine and Dentistry, James Cook University, Douglas, Queensland, Australia
Search for other papers by Vasant V Shenoy in
Google Scholar
PubMed
Summary
Autoimmune hypophysitis (AH) has been previously described in a typical demographic population, primarily women in the reproductive age group and perinatal period. The era of immune modulation using anti-cytotoxic T-lymphocyte-associated antigen 4 biological therapy (ipilimumab) against advanced cancers like metastatic melanomas has now resulted in a new form of hypophysitis being increasingly recognised under a spectrum of immune-related adverse events. Drug-related AH often presents with subtle symptoms and a pituitary mass, with the potential for fatality necessitating wide awareness and a high index of clinical suspicion given that it is usually treatable. We describe below two cases of AH within the last three months at our centre, which were treated with different regimens and produced good endocrine outcomes.
Learning points
-
AH is a new and defined clinical entity occurring as a side effect of ipilimumab, which enhances immune-mediated destruction of metastatic melanoma.
-
It can present insidiously and have life-threatening complications related to hypocortisolism, hence a high index of clinical suspicion must be exerted by treating physicians, and seems to result in resolution of pituitary masses and variable improvements of pituitary function.
-
Clinical improvement, radiological resolution of pituitary masses and variable normalisation of pituitary function are possible with early treatment with high-dose oral or i.v. steroids and hormone replacement therapy, although duration and dosing protocols are unclear at this stage.
-
Ipilimumab should continue to be prescribed as treatment for metastatic melanoma; however, close clinical observation of patient's progress must be maintained while they are on this drug.
-
Predictive factors for onset of AH remain unclear and it is imperative that AH is distinguished from pituitary metastases.
-
Further studies are required to determine the safety of continuing therapy with ipilimumab in patients who have developed AH while on treatment.