Pancreatic endocrine neoplasms: a current update on genetics and imaging

Artificial intelligence as a noninvasive tool for pancreatic cancer prediction and diagnosis

Pancreatic cancer (PC) has a low incidence rate but a high mortality, with patients often in the advanced stage of the disease at the time of the first diagnosis. If detected, early neoplastic lesions are ideal for surgery, offering the best prognosis. Preneoplastic lesions of the pancreas include pancreatic intraepithelial neoplasia and mucinous cystic neoplasms, with intraductal papillary mucinous neoplasms being the most commonly diagnosed. Our study focused on predicting PC by identifying early signs using noninvasive techniques and artificial intelligence (AI). A systematic English literature search was conducted on the PubMed electronic database and other sources. We obtained a total of 97 studies on the subject of pancreatic neoplasms. The final number of articles included in our study was 44, 34 of which focused on the use of AI algorithms in the early diagnosis and prediction of pancreatic lesions. AI algorithms can facilitate diagnosis by analyzing massive amounts of data in a short period of time. Correlations can be made through AI algorithms by expanding image and electronic medical records databases, which can later be used as part of a screening program for the general population. AI-based screening models should involve a combination of biomarkers and medical and imaging data from different sources. This requires large numbers of resources, collaboration between medical practitioners, and investment in medical infrastructures.

Toxic effects of waterborne benzylparaben on the growth, antioxidant capacity and lipid metabolism of Nile tilapia (Oreochromis niloticus)

Benzylparaben (BzP) is a potential endocrine disruptor; however, its antioxidant defense, lipotoxicity and underlying mechanism of BzP in aquatic organisms are unknown. This study investigated the impacts of waterborne low-, environmental-related and high-level benzylparaben on the growth, antioxidant capacity, lipid metabolism and lipidomic response of Nile tilapia (Oreochromis niloticus). Juvenile tilapia (0.60 ± 0.11 g) were exposed to 0, 5, 50, 500 and 5000 ng/L benzylparaben for 8 weeks in quadruplicate for each group. Benzylparaben increased the body crude fat content but decreased brain acetylcholinesterase activity in O. niloticus. Benzylparaben caused oxidative stress, leading to hepatic morphology damage and lipid metabolism disorders in fish. Lipidomic analysis identified 13 lipid classes in fish liver. Benzylparaben exposure induced metabolic disorders of glycerol phospholipids, glycerolipids and sphingomyelins in fish liver. These findings indicate that environmentally related benzylparaben levels (5 to 50 ng/L) could induce an antioxidant response, result in triglyceride accumulation, and increase adipocyte formation and fatty acid intake in tilapia. However, high benzylparaben concentrations inhibit lipid deposition, presumably due to the effects of the antioxidant system, and induce tissue inflammation. Therefore, this study provides new insights into the toxic effects and potential mechanism of benzylparaben in fish, especially from the aspect of lipid metabolism.

The added value of intravoxel incoherent motion diffusion weighted imaging parameters in differentiating high-grade pancreatic neuroendocrine neoplasms from pancreatic ductal adenocarcinoma

The aim of the present study was to investigate the potential significance of intravoxel incoherent motion (IVIM)-diffusion weighted imaging (DWI) in differentiating high-grade pancreatic neuroendocrine neoplasms (pNENs) from pancreatic ductal adenocarcinoma (PDAC). A total of 50 patients, including 37 patients with PDAC and 13 patients with high-grade pNENs, underwent pancreatic multiple b-values DWI with 15 b-values including 0, 10, 20, 40, 60, 80, 100, 150, 200, 400, 800, 1,000, 1,200, 1,500 and 2,000 sec/mm². Standard apparent diffusion coefficient (ADC_standard) and IVIM parameter [slow apparent diffusion coefficient (D_slow), fast apparent diffusion coefficient (D_fast), fraction of fast apparent diffusion coefficient (ƒ)] values of PDAC and pNENs were compared. P<0.05 was considered to indicate a statistically significant difference. Receiver operating characteristics analysis was performed in order to evaluate the diagnostic potential of IVIM parameters for differentiating high-grade pNENs from PDAC. D_slow of pNENs was significantly lower compared with that of PDAC (0.460 vs. 0.579×10⁻³ mm²/sec; P=0.001). D_fast of pNENs was significantly higher compared with that of PDAC (13.361 vs. 4.985×10⁻³ mm²/sec; P<0.001). Area under the curve of D_slow, D_fast and combined D_slow and D_fast was 0.793, 0.863 and 0.885 respectively. The specificity and sensitivity of D_slow≤0.472×10⁻³ mm²/sec were 97.3 and 53.9%, respectively, for differentiating high-grade pNENs from PDAC. The specificity and sensitivity of D_fast >9.58×10⁻³ mm²/sec were 91.9 and 69.2%, respectively, for differentiating high-grade pNENs from PDAC. When D_slow and D_fast were combined, the specificity and sensitivity for differentiating high-grade pNENs from PDAC were 76.9 and 100%, respectively. Taken together, these results indicated that the diffusion-associated parameter D_slow and the perfusion-associated parameter D_fast of IVIM-DWI may differentiate high-grade pNENs from PDAC with high diagnostic accuracy, and that IVIM-DWI may be a valuable biomarker in differentiating pancreatic neoplasms.

A severe but reversible reduction in insulin sensitivity is observed in patients with insulinoma

BACKGROUND

Hypoglycemic manifestations are highly variable in patients with an insulinoma and largely independent of tumour size and severity of insulin hypersecretion.

OBJECTIVES

We investigated the clinical, biological and tumoral characteristics of insulinomas in a large monocentric series of patients and we evaluated their insulin sensitivity before and after successful pancreatic surgery.

PATIENTS AND METHODS

This was a retrospective analysis of 40 patients treated for an insulinoma between 1982 and 2012 in our academic hospital. Insulin sensitivity and beta cell function were evaluated by a HOMA test outside hypoglycaemic episodes in a large subset of these patients.

RESULTS

The mean age at onset of symptoms was 48.8±20.1 years and the mean age at diagnosis was 50.7±19.9 years. Neuroglycopenic symptoms were observed in 90% of patients. The most effective preoperative imaging technique to localize the tumour was endoscopic ultrasound. Insulin sensitivity was greatly reduced in patients with insulinoma (38.9%±22.3%), while beta cells function was increased (359.0±171.5%), but to a variable extent (range: 110.6-678.6%). After complete resection of the tumour and remission of hypoglycemic episodes, insulin sensitivity increased in all evaluated subjects (72.8±36.7%) and normalized in the majority.

CONCLUSION

Although neuroglycopenic symptoms are present in most patients, diagnosis of insulinoma is often delayed. Endoscopic ultrasound remains the most sensitive preoperative technique to localize the tumour. We also show that in response to chronic hyperinsulinemia, patients with insulinoma develop protective mechanisms responsible for a marked insulin resistance, which is reversible after complete resection of the tumour.

Pancreatic Imaging

Imaging of the endocrine pancreas is dominated by neuroendocrine tumors, a diverse category of neoplasms that may or may not cause symptoms from hormone hypersecretion. These tumors may also be evidence of several different genetic syndromes. Understanding the usefulness of different imaging modalities and entities that simulate neuroendocrine tumors is key for both radiologists and referring physicians.

Role of (68)Ga-DOTATATE PET/CT in patients with multiple endocrine neoplasia type 1 (MEN1)

Multiple endocrine neoplasia type 1 (MEN1) is a hereditary syndrome predisposing to many endocrine and neuroendocrine tumors (NET). Conventional imaging (CI) cannot provide satisfactory results for all the different types of MEN1-related tumors. Objective of this prospective observational study was to evaluate the role of (68)Ga-DOTATATE PET/CT in MEN1 compared to CI. Diagnostic performance of (68)Ga-DOTATATE PET/CT for the detection of NET was evaluated as well as the prognostic role of SUVmax. Eighteen patients with genetically confirmed MEN1 were evaluated by (68)Ga-DOTATATE PET/CT, endoscopic ultrasounds, multidetector-row computed tomography, magnetic resonance imaging, and hormone/markers serum measurements. Four MEN1-related tumor sites (pancreas, pituitary, parathyroids, adrenals) were considered. Sensitivity and specificity of (68)Ga-DOTATATE PET/CT for the detection of NET were calculated. There was (68)Ga-DOTATATE PET/CT uptake in 11/11 patients with pancreatic lesions, in 9/12 with pituitary adenoma, in 5/15 with parathyroid enlargements, and in 5/7 with adrenal lesions. (68)Ga-DOTATATE PET/CT showed sensitivity and specificity of 100 and 100 % in pancreas, 75 and 83 % in pituitary, 28 and 100 % in parathyroids, and 62.5 and 100 % in adrenals, respectively. Compared with CI, no significant difference in sensitivity for pancreas, pituitary, and adrenals was found, while CI had a better sensitivity for parathyroids (p = 0.002). On the ROC analysis, progression of pancreatic lesions was significantly associated to SUVmax <12.3 (p < 0.05). (68)Ga-DOTATATE PET/CT is greatly helpful in the work-up of MEN1 providing a panoramic view of MEN1-related lesions. There is also a prognostic role of (68)Ga-PET in patients with MEN1-pancreatic lesions.

A Novel Deletion Mutation in the MEN1 Gene in a Patient with Prolactinoma and a Family History of Pancreatic Tumors

OBJECTIVE

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant tumor syndrome caused by mutations in the MEN1 gene. Mutations in this tumor suppressor gene are often associated with neuroendocrine tumors. Here we describe a novel deletion mutation at codon 304 in the MEN1 gene of a patient with a prolactinoma and strong family history of pancreatic tumors.

METHODS

We describe the patient's clinical course and mutational analysis and review the relevant literature.

RESULTS

A 30-year-old pregnant female was referred to our institution's psychological department for treatment of depression. She had developed a prolactinoma at age 17 and was being treated with 1 mg/week of cabergoline. A medical interview revealed a family history of pancreatic islet cell and other tumors; her mother died of pancreatic cancer, her brother is living with gastrinoma, and her sister died of leiomyosarcoma. Extensive examinations performed after delivery, including laboratory tests and computed tomography (CT) scans, did not reveal any other tumors. Mutational analysis of the MEN1 gene identified a heterozygous deletion mutation (c911_914delAGGT) at codon 304. This mutation produces a frameshift at p.304Lys and might disturb the splicing of intron 6 due to the lack of a donor site. The predicted menin protein from the mutated allele is truncated at amino acid 328.

CONCLUSION

We report a novel deletion mutation (c911_914delAGGT) in the MEN1 gene that was likely associated with the patient's prolactinoma and her strong family history of pancreatic tumors.