Unawareness of postprandial hypoglycemia for 5 years was identified in a 66-year-old man at a local clinic. The patient was referred to our hospital because of this first awareness of hypoglycemia (i.e. lightheadedness and impaired consciousness) developing after lunch. In a 75 g oral glucose tolerance test, the plasma glucose concentration was decreased to 32 mg/dL (1.8 mmol/L) at 150 min with relatively high concentrations of insulin (8.1 μU/mL), proinsulin (70.3 pmol/L), and C-peptide (4.63 ng/mL). In a prolonged fasting test, the plasma glucose concentration was decreased to 43 mg/dL (2.4 mmol/L) at 66 h with an insulin concentration of 1.4 μU/mL and a C-peptide concentration of 0.49 ng/mL. Computed tomography showed an 18 mm hyperenhancing tumor in the uncinate process of the pancreas. A selective arterial calcium stimulation test showed an elevated serum insulin concentration in the superior mesenteric artery. The patient was then diagnosed with insulinoma and received pancreaticoduodenectomy. Continuous glucose monitoring (CGM) using the Dexcom G6 system showed unawareness of hypoglycemia mainly during the daytime before surgery. When the sensor glucose value was reduced to 55 mg/dL (3.1 mmol/L), the Dexcom G6 system emitted an urgent low glucose alarm to the patient four times for 10 days. Two months after surgery, an overall increase in daily blood glucose concentrations and resolution of hypoglycemia were shown by CGM. We report a case of insulinoma with unawareness of postprandial hypoglycemia in the patient. The Dexcom G6 system was helpful for assessing preoperative hypoglycemia and for evaluating outcomes of treatment by surgery.
Insulinoma occasionally leads to postprandial hypoglycemia.
The CGM system is useful for revealing the presence of unnoticed hypoglycemia and for evaluating treatment outcomes after surgical resection.
The Dexcom G6 system has an urgent low glucose alarm, making it particularly suitable for patients who are unaware of hypoglycemia.
A 55-year-old patient was admitted to our department for the management of a repetitive alteration of consciousness. Biological investigation results were consistent with endogenous hyperinsulinemic hypoglycemia. Insulinoma was therefore suspected. Abdominal computed tomography and endoscopic ultrasound showed no obvious pancreatic mass.Somatostatin receptor scintigraphy showed abnormal radioactive uptake in both the pancreatic tail and the uncinate process. Contrariwise, abdominal magnetic resonance imaging showed a unique lesion in the pancreas tail. The patient was then proposed for pancreatic surgery. Both intraoperative manual palpation and intraoperative ultrasonography of the pancreas showed a single corporal lesion of 1.5 cm. No lesion was found in the uncinate process. After a left pancreatectomy, the lesion was histopathologically confirmed to be a well-differentiated neuroendocrine tumor. The symptoms of the patient resolved almost immediately following the surgery. The follow-up is one and a half years to date.
The exact preoperative localization of the pancreatic mass remains the most challenging part of insulinoma diagnostic workup.
The radiologist’s experience is the best warrantor to a precise localization of the tumor.
111In-DTPA-octreotide uptake in the pancreatic uncinate process may be physiological and its interpretation must, therefore, be vigilant.
Manual palpation along with intraoperative ultrasonography is considered as the most effective method for the localization of insulinomas during open surgery.
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.
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.
A 33-year-old female presented in 2013 with left flank pain. Ultrasound and MRI pelvis showed a complex mass 9 × 7 cm arising from the left ovary suggestive of ovarian torsion. She underwent a laparoscopic cystectomy, but the patient was lost to follow-up. Three years later, she presented with abdominal distension. Ultrasound and CT scan revealed a solid left ovarian mass with ascites and multiple peritoneal metastasis. Investigations showed elevated CA 125, CA 19-9. Ovarian malignancy was suspected. She underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy on November 2016. The histopathology confirmed a well-differentiated thyroid cancer of ovarian origin with features of a papillary follicular variant without evidence of ovarian cancer and the thyroglobulin (Tg) level was elevated, more than 400 consistent with the diagnosis of malignant struma ovarii. The follow-up post-surgery showed normalization of CA 125, CA 19-9 and Tg. The patient underwent total thyroidectomy on January 2017. The histology was benign excluding thyroid cancer metastases to the ovary. She was started on thyroxine suppression, following which she received two ablation doses 131iodine (131I) each 5.3 GBq. The Tg remains slightly elevated at less than 10. 131I WBS showed no residual neck uptake and no distant avid metastasis. She was planned for molecular analysis which may indicate disease severity. We describe a case of malignant struma ovarii with widespread metastatic dissemination and a good response to surgery and 131I treatment without recurrence after 5 years of follow-up. The Tg remains slightly elevated indicating minimal stable residual disease.
Malignant struma ovarii is a rare disease; diagnosis is difficult and management is not well defined.
Presentation may mimic advanced carcinoma of the ovary.
Predominant sites of metastasis are adjacent pelvic structures.
Thyroidectomy and 131iodine therapy should be considered. The management should be similar to that of metastatic thyroid cancer.
The Covid-19 vaccination has been rapidly implemented among patients with cancer. We present two cases of patients with endocrine tumours who developed lymphadenopathy following a Covid-19 vaccination. In the case of a patient with multiple endocrine neoplasia (MEN) 1 syndrome, an 18-fluorodeoxyglucose (18FDG)-PET/CT showed positive axillary lymph nodes. Further work-up with fine needle aspiration showed a reactive pattern following a Covid-19 vaccination in the ipsilateral arm shortly before the 18FDG-PET/CT. A second patient, in follow-up for thyroid cancer, developed clinical supraclavicular lymphadenopathy after a Covid-19 vaccination. Follow-up ultrasound proved the lesion to be transient. These cases demonstrate lymphadenopathy in response to a Covid-19 vaccination in two patients susceptible to endocrine tumours and metastatic disease. With growing evidence about the pattern and occurrence of lymphadenopathy after mRNA Covid-19 vaccination, recommendations for scheduling and interpretation of imaging among cancer patients should be implemented to reduce equivocal findings, overdiagnosis, and overtreatment, while maintaining a good standard of care in oncological follow-up.
Reactive lymphadenopathy is very common after an mRNA vaccination against Covid-19 and should be part of the differential diagnosis in patients with endocrine tumours who recently received a Covid-19 mRNA vaccination and present with an ipsilateral lymphadenopathy.
A good vaccine history is essential in assessing the risk for lymphadenopathy and if possible, screening imaging in patients with endocrine tumours should be postponed at least 6 weeks after the previous vaccination.
For now, a multidisciplinary care approach is recommended to determine the necessary steps in the diagnostic evaluation of lymphadenopathy in the proximity of a Covid-19 vaccination.
A paired homeodomain transcription factor, PAX6 (paired-box 6), is essential for the development and differentiation of pancreatic endocrine cells as well as ocular cells. Despite the impairment of insulin secretion observed in PAX6-deficient mice, evidence implicating causal association between PAX6 gene mutations and monogenic forms of human diabetes is limited. We herein describe a 33-year-old Japanese woman with congenital aniridia who was referred to our hospital because of her uncontrolled diabetes with elevated hemoglobin A1c (13.1%) and blood glucose (32.5 mmol/L) levels. Our biochemical analysis revealed that her insulin secretory capacity was modestly impaired as represented by decreased 24-h urinary C-peptide levels (38.0 μg/day), primarily explaining her diabetes. Intriguingly, there was a trend toward a reduction in her serum glucagon levels as well. Based on the well-recognized association of PAX6 gene mutations with congenital aniridia, we screened the whole PAX6 coding sequence, leading to an identification of a heterozygous Gln135* mutation. We tested our idea that this mutation may at least in part explain the impaired insulin secretion observed in this patient. In cultured pancreatic β-cells, exogenous expression of the PAX6 Gln135* mutant produced a truncated protein that lacked the transcriptional activity to induce insulin gene expression. Our observation together with preceding reports support the recent attempt to include PAX6 in the growing list of genes causally responsible for monogenic diabetes. In addition, since most cases of congenital aniridia carry PAX6 mutations, we may need to pay more attention to blood glucose levels in these patients.
PAX6 Gln135* mutation may be causally associated not only with congenital aniridia but also with diabetes.
Blood glucose levels may deserve more attention in cases of congenital aniridia with PAX6 mutations.
Our case supports the recent attempt to include PAX6 in the list of MODY genes, and Gln135* may be pathogenic.
Treatment of insulinoma can be challenging, while surgical resection is considered the first line. When surgery is contraindicated or is refused, minimally invasive procedures such as selective arterial embolization, local ablative techniques including alcohol ablation, radiofrequency ablation and microwave ablation are being used of late. The world’s first microwave ablation of insulinoma was performed in 2015, after which there have been only a handful of reported cases. A 78-year-old female presented with painful swelling of the left lower limb. She was drowsy and was previously misdiagnosed as epilepsy when she had similar episodes since 2 years ago. She had hypoglycaemia with high serum insulin and C-peptide, and mildly high adjusted calcium, serum prolactin. MRI did not show pituitary adenoma. Lower limb venous duplex scan showed left lower limb deep vein thrombosis for which she was treated with anticoagulation. CT of the abdomen showed a tumour measuring 1.8 cm, located in the antero-superior aspect of the body of the pancreas, with the superior surface being abutted by the splenic artery and the inferior surface being 3 mm above the pancreatic duct, suggestive of an insulinoma. Selective transcatheter arterial embolization of the pancreatic tumour was attempted but was abandoned due to multiple small feeding arteries. Microwave ablation of the tumour was performed successfully. Since there was a possibility of the ablation being compromised due to the heat sink at the splenic artery, 2 mL of 99% alcohol was injected into the rim of the tumour near the artery. She was subsequently normoglycaemic. She defaulted follow up for repeat imaging of pancreas and screening for MEN1 syndrome due to the impact of the COVID-19 pandemic. Minimally invasive procedures are preferred over surgery in selected patients with insulinoma, out of which microwave ablation could be preferentially recommended due to its efficacy and minimal complications. We report the first case of MWA performed in combination with AA in successfully treating insulinoma to our knowledge. This is also the first reported case of DVT associated with isolated insulinoma prior to intervention, though it is rarely reported in MEN1 syndrome.
Novel therapeutic minimally invasive procedures are successful in treating selected cases of insulinoma.
Microwave ablation could be recommended preferentially over selective trans-arterial embolization, and radiofrequency ablation in treating insulinoma due to its efficacy and minimal complications.
We report the first case of microwave ablation performed in combination with alcohol ablation in successfully treating insulinoma to our knowledge.
Royce P VincentDepartment of Clinical Biochemistry, King’s College Hospital NHS Foundation Trust, Denmark Hill, London, UK Faculty of Life Sciences and Medicine, School of Life Course Sciences, King’s College London, London, UK
Ashley B GrossmanOxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, UK Barts and the London School of Medicine, Centre for Endocrinology, William Harvey Institute, London, UK Neuroendocrine Tumour Unit, Royal Free Hospital, London, UK
Georgios K DimitriadisDepartment of Endocrinology ASO/EASO COM, King ’s College Hospital NHS Foundation Trust, Denmark Hill, London, UK Obesity, Type 2 Diabetes and Immunometabolism Research Group, Department of Diabetes, Faculty of Life Sciences, School of Life Course Sciences, King’s College London, London, UK Division of Reproductive Health, Warwick Medical School, University of Warwick, Coventry, UK
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.
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.
Multiple endocrine neoplasia type 1 NM_001370259.2(MEN1):c.466G>C(p.Gly156Arg) is characterized by tumors of various endocrine organs. We report on a rare, growth hormone-releasing hormone (GHRH)-releasing pancreatic tumor in a MEN1 patient with a long-term follow-up after surgery. A 22-year-old male with MEN1 syndrome, primary hyperparathyroidism and an acromegalic habitus was observed to have a pancreatic tumor on abdominal CT scanning, growth hormone (GH) and insulin-like growth factor 1 (IGF1) were elevated and plasma GHRH was exceptionally high. GHRH and GH were measured before the treatment and were followed during the study. During octreotide treatment, IGF1 normalized and the GH curve was near normal. After surgical treatment of primary hyperparathyroidism, a pancreatic tail tumor was enucleated. The tumor cells were positive for GHRH antibody staining. After the operation, acromegaly was cured as judged by laboratory tests. No reactivation of acromegaly has been seen during a 20-year follow-up. In conclusion, an ectopic GHRH-producing, pancreatic endocrine neoplasia may represent a rare manifestation of MEN1 syndrome.
Clinical suspicion is in a key position in detecting acromegaly.
Remember genetic disorders with young individuals having primary hyperparathyroidism.
Consider multiple endocrine neoplasia type 1 syndrome when a person has several endocrine neoplasia.
Acromegaly may be of ectopic origin with patients showing no abnormalities in radiological imaging of the pituitary gland.
Benjamin SolomonDepartment of Medical Oncology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia Sir Peter MacCallum Department of Oncology, The University of Melbourne, Victoria, Australia
Adrenocortical carcinoma is a rare disease with poor prognosis whose clinical heterogeneity can at times present a challenge to accurate and timely diagnosis. We present the case of a patient who presented with extensive pulmonary lesions, mediastinal and hilar lymphadenopathy and an adrenal mass in whom the oncological diagnosis was initially uncertain. Through the use of immunohistochemistry, biochemistry and genomic testing, an accurate diagnosis of adrenocortical carcinoma was ultimately made which resulted in more directed treatment being administered. The use of multidisciplinary input and genomics to aid in diagnosis and prognosis of adrenocortical carcinoma is discussed.
Adrenocortical carcinomas can present a diagnostic challenge to clinicians given it is a rare malignancy with significant clinical heterogeneity.
Specialist multidisciplinary team input is vital in the diagnosis and management of adrenocortical carcinomas.
Hormonal testing is recommended in the diagnostic workup of adrenal masses, even in the absence of overt clinical signs/symptoms of hormone excess.
Immunostaining for the highly sensitive and specific steroidogenic factor-1 is vital for accurate diagnosis.
Genomics can provide prognostic utility in management of adrenocortical carcinoma.