A case of pancreatic neuroendocrine tumor in a patient with neurofibromatosis-1

Periampullary duodenal neuroendocrine tumor in a patient with neurofibromatosis-1: A case report

BACKGROUND

Patients with neurofibromatosis type 1 (NF1) are exposed to a higher risk of developing neuroendocrine tumors (NETs). Periampullary neuroendocrine neoplasms (NENs) in NF1 patients primarily affect the duodenum and periampullary region.

CASE SUMMARY

A 50-year-old male patient was admitted to our hospital due to progressive skin and scleral yellowing for over 6 months. An abdominal contrast-enhanced computed tomography scan revealed a tumor in the periampullary region, which measured 1.2 cm × 1.4 cm in size and showed a progressive enhancement. Magnetic resonance cholangiopancreatography indicated the dilation of intrahepatic and extrahepatic bile ducts. The patient was diagnosed with an ampullary tumor with the possibility of malignancy. A Whipple procedure was performed. Microscopically, the duodenum tumor was found to invade the mucosa, sphincter, and muscular layer of the duodenal papilla. Histologic hematoxylin and eosin staining confirmed the presence of duodenal G1 NET. Subsequently, a bibliometric analysis was performed to evaluate the state of NEN research. Publications about periampullary NENs showed an annual increase, with most of them focusing on the treatment and diagnosis of NENs.

CONCLUSION

This article reported a case of periampullary duodenal NET in a patient with NF1, and a bibliometric analysis was conducted.

Genetics, Genomics and Emerging Molecular Therapies of Pancreatic Cancer

The number of cases of pancreatic cancers in 2019 in Poland was 3852 (approx. 2% of all cancers). The course of the disease is very fast, and the average survival time from the diagnosis is 6 months. Only <2% of patients live for 5 years from the diagnosis, 8% live for 2 years, and almost half live for only about 3 months. A family predisposition to pancreatic cancer occurs in about 10% of cases. Several oncogenes in which somatic changes lead to the development of tumours, including genes BRCA1/2 and PALB2, TP53, CDKN2A, SMAD4, MLL3, TGFBR2, ARID1A and SF3B1, are involved in pancreatic cancer. Between 4% and 10% of individuals with pancreatic cancer will have a mutation in one of these genes. Six percent of patients with pancreatic cancer have NTRK pathogenic fusion. The pathogenesis of pancreatic cancer can in many cases be characterised by homologous recombination deficiency (HRD)-cell inability to effectively repair DNA. It is estimated that from 24% to as many as 44% of pancreatic cancers show HRD. The most common cause of HRD are inactivating mutations in the genes regulating this DNA repair system, mainly BRCA1 and BRCA2, but also PALB2, RAD51C and several dozen others.

Neurofibromatosis from Head to Toe: What the Radiologist Needs to Know

Neurofibromatosis type 1 (NF1) and neurofibromatosis type 2 (NF2) are autosomal dominant inherited neurocutaneous disorders or phakomatoses secondary to mutations in the NF1 and NF2 tumor suppressor genes, respectively. Although they share a common name, NF1 and NF2 are distinct disorders with a wide range of multisystem manifestations that include benign and malignant tumors. Imaging plays an essential role in diagnosis, surveillance, and management of individuals with NF1 and NF2. Therefore, it is crucial for radiologists to be familiar with the imaging features of NF1 and NF2 to allow prompt diagnosis and appropriate management. Key manifestations of NF1 include café-au-lait macules, axillary or inguinal freckling, neurofibromas or plexiform neurofibromas, optic pathway gliomas, Lisch nodules, and osseous lesions such as sphenoid dysplasia, all of which are considered diagnostic features of NF1. Other manifestations include focal areas of signal intensity in the brain, low-grade gliomas, interstitial lung disease, various abdominopelvic neoplasms, scoliosis, and vascular dysplasia. The various NF1-associated abdominopelvic neoplasms can be categorized by their cellular origin: neurogenic neoplasms, interstitial cells of Cajal neoplasms, neuroendocrine neoplasms, and embryonal neoplasms. Malignant peripheral nerve sheath tumors and intracranial tumors are the leading contributors to mortality in NF1. Classic manifestations of NF2 include schwannomas, meningiomas, and ependymomas. However, NF2 may have shared cutaneous manifestations with NF1. Lifelong multidisciplinary management is critical for patients with either disease. The authors highlight the genetics and molecular pathogenesis, clinical and pathologic features, imaging manifestations, and multidisciplinary management and surveillance of NF1 and NF2. Online supplemental material is available for this article. ^©RSNA, 2022.

Idiopathic gross dilatation of the pancreatic duct with exocrine insufficiency in a patient with type 1 neurofibromatosis

Pancreatic duct dilatation occurs in conditions including chronic pancreatitis, pancreatic carcinoma and intraductal papillary mucinous neoplasms. Although several pancreatic benign and malignant tumours have been reported in association with type 1 neurofibromatosis, an association with gross pancreatic duct dilatation or ectasia has not been previously published. We report on a patient with type 1 neurofibromatosis found to have idiopathic gross pancreatic duct dilatation and exocrine insufficiency. A 51-year-old female with type 1 neurofibromatosis presented with weight loss and steatorrhoea. Computed tomography and magnetic resonance cholangiopancreatography showed a possible cystic lesion in the head of the pancreas, a grossly dilated main pancreatic duct and minimal thinned out pancreatic parenchyma. Endosonography confirmed diffuse dilatation of the pancreatic duct with no evidence of a separate cystic neoplasm. Endosonography-guided aspiration revealed non-mucinous, clear fluid with high amylase and normal carcinoembryonic antigen levels. The patient was prescribed pancreatic enzyme supplementation and showed symptomatic improvement. Associations between type 1 neurofibromatosis and pancreatic duct ectasia or chronic pancreatitis have not been reported, and this finding may be coincidental. Clinical presentation in conjunction with multimodal imaging and biochemical and cytological fluid analysis did not reveal the aetiology of the ectatic duct system and attenuated glandular tissue in this patient which is most likely congenital.

What Are the Place and Modalities of Surgical Management for Pancreatic Neuroendocrine Neoplasms? A Narrative Review

Pancreatic neuroendocrine neoplasms (panNENs) are a heterogeneous group of tumors derived from cells with neuroendocrine differentiation. They are considered malignant by default. However, their outcomes are variable depending on their presentation in the onset of hereditary syndromes, hormonal secretion, grading, and extension. Therefore, although surgical treatment has long been suggested as the only treatment of pancreatic neuroendocrine neoplasms, its modalities are an evolving landscape. For selected patients (small, localized, non-functional panNENs), a "wait and see" strategy is suggested, as it is in the setting of multiple neuroendocrine neoplasia type 1, but the accurate size cut-off remains to be established. Parenchyma-sparring pancreatectomy, aiming to limit pancreatic insufficiency, are also emerging procedures, which place beyond the treatment of insulinomas and small non-functional panNENs (in association with lymph node picking) remains to be clarified. Furthermore, giving the fact that the liver is generally the only metastatic site, surgery keeps a place of choice alongside medical therapies in the treatment of metastatic disease, but its modalities and extensions are still a matter of debate. This narrative review aims to describe the current recommended surgical management for pancreatic NENs and controversies in light of the actual recommendations and recent literature.

Frequency, Progression, and Current Management: Report of 16 New Cases of Nonfunctional Pancreatic Neuroendocrine Tumors in Tuberous Sclerosis Complex and Comparison With Previous Reports

Background: Tuberous sclerosis complex (TSC) is a genetic condition that causes benign tumors to grow in multiple organ systems. Nonfunctional pancreatic neuroendocrine tumors (PNETs) are a rare clinical feature of TSC with no specific guidelines outlined for clinical management at this time. Our purpose is to calculate the frequency of nonfunctional PNETs as well as characterize the presentation, current clinical management, and assess the impact of systemic mammalian target of rapamycin (mTOR) on nonfunctional PNETs in TSC.

Methods: This retrospective chart review was performed by a query of the TS Alliance's Natural History Database and the Cincinnati Children's Hospital TSC Database for patients with nonfunctional PNET. Clinical data from these two groups was summarized for patients identified to have a nonfunctional PNET and compared to previously reported cases with TSC and nonfunctional PNETs.

Results: Our calculated frequency of nonfunctional PNETs is 0.65%. We identified 16 individuals, nine males and seven females, with a median age of 18.0 years (interquartile range: −15.5 to 25.5). Just over half (56.3%, n = 9) of the patients provided results from genetic testing. Six had pathogenic variants in TSC2 whereas three had pathogenic variants in TSC1. The average age at PNET diagnosis was 15.0 years (range: 3–46 years). Almost all individuals were diagnosed with a PNET during routine TSC surveillance, 56.3% (n = 9) by MRI, 12.5% (n = 2) by CT, 25% (n = 4) by ultrasound, and 6.2% (n = 1) through a surgical procedure. Follow up after diagnosis involved 68.8% (n = 11) having serial imaging and nine of the sixteen individuals proceeding with surgical removal of the PNET. Eight individuals had a history of using systemic mTOR inhibitors. Tumor growth rate was slightly less in individuals taking an mTOR inhibitor (−0.8 mm/yr, IQR: −2.3 to 2.2) than those without (1.6 mm/yr; IQR: −0.99 to 5.01, p > 0.05).

Conclusions: Nonfunctional PNETs occurred at younger ages in our TSC cohort and more commonly compared to ages and prevalence reported for the general population. PNETs in patients on systemic mTOR inhibitors had lower rates of growth. The outcome of this study provides preliminary evidence supporting the use of mTOR inhibitor therapy in conjunction with serial imaging as medical management for nonfunctional PNETs as an alternative option to invasive surgical removal.

Cystic Pancreatic Neuroendocrine Tumor in a Patient with Neurofibromatosis Type 1

Neurofibromatosis type 1 (NF-1) is strongly associated with neurofibromas and malignancies. Solid pancreatic neuroendocrine tumors (PanNETs) have been recently reported in patients with NF-1. PanNETs are always solid and rarely present with a cystic appearance due to central necrosis and hemorrhage caused by rapid growth. A 33-year-old female diagnosed with NF-1 at age 16 was referred for evaluation of a pelvic mass found on abdominal ultrasound. Magnetic resonance imaging showed a 6 cm solid pelvic mass adjacent to the left external iliac artery, and contrast-enhanced computed tomography scan showed a 3-cm solid para-aortic mass and a 3-cm cystic mass in the pancreatic tail. Endoscopic ultrasonography showed a cystic tumor with necrotic tissue and septa. Preoperative diagnosis was pancreatic cystic malignancy with para-aortic lymph node metastasis accompanied with a pelvic neurofibroma. These lesions were resected simultaneously. The specimen resected from the pancreas showed a necrotizing cystic tumor invading abutting lymph nodes. Immunohistochemical analysis showed positive chromogranin A and synaptophysin. The Ki-67 index was <1%, and the mitotic count was 1/10 in high power field. Therefore, a non-functional PanNET (grade G1) was diagnosed. The pelvic and para-aortic tumors were both neurofibromas. A cystic appearance is atypical for PanNET and makes preoperative diagnosis difficult. To the best of our knowledge, this is the first report of a cystic PanNET in a patient with NF-1.

Pancreatic Gastrinoma, Gastrointestinal Stromal Tumor (GIST), Pheochromocytoma, and Hürthle Cell Neoplasm in a Patient with Neurofibromatosis Type 1: A Case Report and Literature Review

BACKGROUND Neurofibromatosis type 1 (NF1) is a multi-tumor syndrome in which affected patients develop malignancies that are rare in the overall population, such as tumors of neural or endocrine origin. CASE REPORT A 67-year-old woman with a clinical diagnosis of NF1 presented with abdominal pain and pneumoperitoneum. She underwent small-bowel resections for a perforated jejunal lesion and a second lesion in the ileum; pathology showed a neurofibroma at the site of the perforation and a 1-cm low-grade GIST, respectively. Additional staging with cross-sectional imaging identified a 3.7-cm pancreatic head mass and a 1.7-cm left adrenal mass; biochemical studies revealed elevated serum gastrin and urinary free metanephrines and catecholamines consistent with pheochromocytoma. Initial surgical management was a left posterior retroperitoneoscopic adrenalectomy. Postoperatively, gallium-68-DOTATOC PET/CT showed uptake in the pancreatic head and a 28-mm left thyroid nodule. Months later, she had an open pancreaticoduodenectomy. Pathology showed pheochromocytoma and a low-grade (G1) gastrinoma involving 2/8 peripancreatic lymph nodes (pT3pN1M0), respectively. Fine-needle aspiration biopsy of the thyroid nodule showed features consistent with a Hürthle cell neoplasm. Genetic testing identified a pathogenic mutation in NF1 and no mutations in BRCA1/2, CDC72, MEN1, or PALB2. The patient continues surveillance, with no evidence of recurrent disease. CONCLUSIONS We report the fifth case of gastrinoma associated with NF1 and the first to arise from the pancreas. This case of a pancreatic neuroendocrine tumor was associated with multiple additional neoplasms. Neuroendocrine tumors found in NF1 should raise suspicion of other malignancies.

Identification of Genomic Alterations in Sporadic Pancreatic Neurogenic Tumors

Pancreatic neurogenic tumors, including schwannoma and neurofibroma, are rare, and their genetic aberrances have not been defined. The present study aimed at investigating the genomic alterations of pancreatic schwannoma and neurofibroma. Two patients with pancreatic schwannoma and 1 patient with neurofibroma, who underwent surgical resection at the First Affiliated Hospital, Sun Yat-sen University between June 2016 and April 2019, were recruited into the study. Their tumor tissues were analyzed by exome sequencing and genome sequencing. Exome sequencing revealed a MUTYH likely pathogenic germline variant in 1 schwannoma with somatic NF2del and NOTCH1 amplification. Pathway enrichment analysis on the other schwannoma case showed that the main abnormal function involved DNA damage repair, mitosis, and cell cycle. In addition, genome sequencing showed the inversion (INV) variant of SPIRE gene and multiple mitochondrial INV variants in both schwannoma cases. Furthermore, exome sequencing revealed NF1del, single nucleotide variation, TP53, and ERBB3 amplification in neurofibroma, whereas genomic duplication/deletion variants and mitochondrial abnormalities were much less than that in schwannoma. In conclusion, variants in NF1 and NF2 genes, amplification of key driver genes, and somatic and mitochondrial INV variants may play important roles in the development of pancreatic schwannoma and neurofibroma.

Surgical management of primary pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors (PanNETs) are the second most common malignancy of the pancreas, and their incidence is increasing. PanNETs are a diverse group of diseases which range from benign to malignant, can be sporadic or associated with genetic mutations, and be functional or nonfunctional. In as much, the treatment and management of PanNETs can vary from a "Wait and See" approach to orthotopic liver transplantation (OLT). Despite this, surgical resection is still the primary treatment modality to achieve cure. This review focuses on the surgical management of PanNETs.

Molecular Genetic Studies of Pancreatic Neuroendocrine Tumors: New Therapeutic Approaches

Pancreatic neuroendocrine tumors (PNETs) arise sporadically or as part of familial syndromes. Genetic studies of hereditary syndromes and whole exome sequencing analysis of sporadic NETs have revealed the roles of some genes involved in PNET tumorigenesis. The multiple endocrine neoplasia type 1 (MEN1) gene is most commonly mutated. Its encoded protein, menin, has roles in transcriptional regulation, genome stability, DNA repair, protein degradation, cell motility and adhesion, microRNA biogenesis, cell division, cell cycle control, and epigenetic regulation. Therapies targeting epigenetic regulation and MEN1 gene replacement have been reported to be effective in preclinical models.

The Role of mTOR in Neuroendocrine Tumors: Future Cornerstone of a Winning Strategy?

The mechanistic target of rapamycin (mTOR) is part of the phosphoinositide-3-kinase (PI3K)/protein kinase B (AkT)/mTOR pathway and owes its name to the inhibitory effect of rapamycin. The mTOR has a central converging role for many cell functions, serving as a sensor for extracellular signals from energy status and nutrients availability, growth factors, oxygen and stress. Thus, it also modulates switch to anabolic processes (protein and lipid synthesis) and autophagy, in order to regulate cell growth and proliferation. Given its functions in the cell, its deregulation is implicated in many human diseases, including cancer. Its predominant role in tumorigenesis and progression of neuroendocrine tumors (NETs), in particular, has been demonstrated in preclinical studies and late clinical trials. mTOR inhibition by everolimus is an established therapeutic target in NETs, but there are no identified predictive or prognostic factors. This review is focused on the role of mTOR and everolimus in NETs, from preclinical studies to major clinical trials, and future perspectives involving mTOR in the treatment of NETs.

The clinical impact of ultrasound contrast agents in EUS: a systematic review according to the levels of evidence

BACKGROUND AND AIMS

The use of contrast-harmonic EUS (CH-EUS) in routine clinical practice is increasing rapidly but is not yet standardized. We present the levels of evidence (LEs) found in the literature to put its clinical outcomes in the appropriate perspective.

METHODS

We conducted a systematic review of the available English-language articles. The LEs were stratified according to the Oxford Centre for Evidence-Based Medicine guidelines.

RESULTS

Overall, 210 articles were included and presented according to different pathologic conditions. For pancreatic solid neoplasms, the pooled sensitivity and specificity in the diagnosis of pancreatic carcinoma were very high (LE 1); quantitative analysis and guidance of FNA were reported as investigational research (LE 2-3). For pancreatic cystic lesions, the identification of neoplastic solid components as hyperenhanced lesions represented a promising application of CH-EUS (LE 2). For lymph nodes, CH-EUS increased the diagnostic yield of B-mode EUS for the detection of malignancy (LE 2). For submucosal tumors, CH-EUS seemed useful for differential diagnosis and risk stratification (LE 2-3). For other applications, differential diagnosis of gallbladder and vascular abnormalities by CH-EUS were reported (LE 2-3).

CONCLUSIONS

The LEs of CH-EUS in the literature have evolved from the initial descriptive studies to multicenter and prospective trials, and even meta-analyses. The differential diagnosis between benign and malignant lesions is the main field of application of CH-EUS. With regard to pancreatic solid neoplasms, the concomitant use of both CH-EUS and EUS-FNA may have additive value in increasing the overall accuracy by overcoming the false-negative results associated with each individual technique. Other applications are promising but still investigational.

Somatic and germline mutations in NETs: Implications for their diagnosis and management

It is now understood that specific somatic and germline mutations may lead to the development of the neuroendocrine tumours (NETs). NETs usually occur as sporadic isolated tumours, although they also may present as part of complex familial endocrine cancer syndromes, such as multiple endocrine neoplasia type 1 (MEN1) and type 2 (MEN2), Von Hippel-Lindau (VHL) and neurofibromatosis syndromes, tuberous sclerosis, Carney triad and dyad, Reed syndrome and polycythaemia-paraganglioma syndromes. Only in MEN2 syndrome is there a specific genotype-phenotype correlation, although in both sporadic and syndromic NETs some gene mutations are associated with specific clinico-pathological features and prognosis. There have been several advances in our understanding of the NETs leading to earlier detection and targeted therapeutic treatment, but given the poor prognosis associated with metastatic NETs, it will be necessary to find new biomarkers for the prediction of malignant potential and to find novel therapeutic targets for NETs.

Gastrinoma and neurofibromatosis type 2: the first case report and review of the literature

Background

Gastroenteropancreatic neuroendocrine tumors have occasionally been described in association with neurofibromatosis type 1, whereas an association with neurofibromatosis type 2 has never been reported.

Case presentation

This report refers to an Italian 69 year old woman with neurofibromatosis type 2 and a pancreatic gastrinoma. In the past she had encephalic meningiomas, a tongue schwannoma and bilateral acoustic neurinomas. She presented with weight loss and a long-term history of diarrhea, responsive to proton pump inhibitors. Upper gastrointestinal endoscopy revealed peptic ulcer of the duodenal bulb. Blood tests were normal, except for the elevation of plasma gastrin (1031 pg/ml; reference value <108) and chromogranin A (337 U/L; reference value <36). After secretin stimulation testing, the plasma gastrin level rose to 3789 pg/ml. The abdomen magnetic resonance imaging and gallium68-DOTATOC positron emission tomography scan demonstrated the presence of a 1.2 x 2 cm lesion in the pancreatic head and a liver metastatis. Pancreatic endoscopic ultrasound with fine needle aspiration revealed cytomorphologic features suggestive of pancreatic gastrinoma. Brain magnetic resonance showed a pituitary microadenoma. There was no evidence of hyperparathyroidism. The genetic test for multiple endocrine neoplasia type 1 syndrome mutation was negative.

Conclusion

This report focuses on the first case of coexistence of gastrinoma with neurofibromatosis type 2. Although the clinical relevance of this association remains to be determined, our case report will surely give cause for due consideration.