Pancreatic neuroendocrine tumors associated with von Hippel Lindau disease: diagnostic and management recommendations

Imaging Update for Hereditary Abdominopelvic Neuroendocrine Neoplasms

ABSTRACT

Neuroendocrine neoplasms have shown a linear increase in incidence and prevalence in recent decades, primarily due to improved cross-sectional imaging, expanded use of endoscopic procedures, and advanced genetic analysis. However, diagnosis of hereditary neuroendocrine tumors is still challenging because of heterogeneity in their presentation, the variety of tumor locations, and multiple associated syndromes. Radiologists should be familiar with the spectrum of these tumors and associated hereditary syndromes. Furthermore, as the assessment of multiple tumor elements such as morphology, biochemical markers, and presence of metastatic disease are essential for the treatment plan, conventional anatomic and functional imaging methods are fundamental in managing and surveilling these cases. Our article illustrates the role of different cross-sectional imaging modalities in diagnosing and managing various hereditary abdominopelvic neuroendocrine tumors.

Single Stage Bilateral Adrenalectomy (Cortical-Sparing) and Pancreatectomy (Corpus-Sparing) in a Patient with Von Hippel-Lindau Disease

Von Hippel-Lindau (VHL) disease is an autosomal dominant syndrome and affects many organs. We aim to report an adult patient with VHL disease having bilateral adrenal pheochromocytoma and multiple neuroendocrine tumors of the pancreas who was successfully treated with simultaneous function-preserving adrenalectomy and pancreatectomy. A 27-year-old woman was admitted to hospital with hypertension. The computed tomography of the abdomen revealed a solid tumor in both adrenal glands with the sizes of 12x7 cm on the right and 4x4 cm on the left. She also had two pancreatic solid masses in the head and three in the tail with varying sizes. The laboratory tests are all within normal limits except elevated 24-hour urinary metanephrine and normetanephrine. I-123 MIBG scanning showed increased uptake in both adrenal glands. Fine needle aspiration biopsy of the tumor on head of pancreas via endoscopic ultrasonography showed neuroendocrine tumor. Those findings were compatible with bilateral pheochromocytoma and multiple pancreatic neuroendocrine tumors and genetic tests revealed the mutation which confirmed the diagnosis of VHL disease. After suppression with alpha-1 inhibitor, right total, left cortical-sparing adrenalectomy, Whipple procedure for the pancreatic head lesions and spleen-preserving distal pancreatectomy were performed and pancreatic corpus was preserved. This case showed that multiple function-preserving procedures can be safely performed with oncological principles in patients with VHL disease.

Non-Interventional Management of Advanced Pancreatic Neuroendocrine Neoplasms in Patients with von Hippel-Lindau Disease

Von Hippel-Lindau (VHL) is a rare autosomal dominant hereditary cancer predisposition syndrome. Patients with VHL have a high risk for developing retinal and central nervous system hemangioblastoma, pheochromocytoma, renal cell carcinoma, and pancreatic neuroendocrine neoplasms (PNEN). About a fifth of patients with VHL will develop PNEN, and only a tenth of them will develop metastatic or unresectable (advanced) PNEN requiring medical intervention. In this review, we performed a literature search for studies, written in English, on the medical interventions for VHL-related localized and advanced PNENs and their clinical outcomes. We detail the various medical interventions for this rare group of patients, including their mode of action and potential efficacy and toxicity. Finally, based on the current literature, we delineate a possible management algorithm for patients with VHL and advanced PNEN. We can conclude that data on the efficacy of various vascular endothelial growth factor (VEGF) receptor inhibitors, and on the efficacy of belzutifan, a novel hypoxia-inducible factor 2 inhibitor, for the management of advanced PNEN in VHL, are scarce. Hence, deduction from the management of sporadic PNEN is required, and is implemented in the proposed management algorithm provided within this review.

Unique Characteristics of Patients with Von Hippel-Lindau Disease Defined by Various Diagnostic Criteria

Von Hippel-Lindau (VHL) disease diagnosis is based on two criteria sets: International criteria (IC, two hemangioblastomas, one hemangioblastoma plus one visceral lesion, or VHL family history/pathogenic variant plus hemangioblastoma/visceral lesion); or Danish criteria (DC, two clinical manifestations, or VHL family history/pathogenic variant plus hemangioblastoma/visceral lesion). We aimed to compare the characteristics of patients with VHL-related pancreatic neuroendocrine tumor (vPNET) meeting either the clinical Danish criteria only (DOC) or IC to those with sporadic PNET (sPNET). The cohort included 33 patients with VHL (20 vPNETs) and 65 with sPNET. In terms of genetic testing and family history of VHL, 90.0% of the patients with vPNET in the IC group had a germline VHL pathogenic variant, and 70.0% had a family history of VHL vs. 20% and 10% in the DOC group, respectively (p < 0.05 for both). Patients with vPNET were younger at diagnosis compared with sPNET (51.6 ± 4.1 vs. 62.8 ± 1.5 years, p < 0.05). Patients in the IC group were younger at diagnosis with VHL, vPNET, pheochromocytoma, or paraganglioma (PPGL) and renal-cell carcinoma (RCC) than those in the DOC group (p < 0.05 for all comparisons). The most prevalent presenting manifestations were hemangioblastoma (42.8%) and PPGL (33.3%) vs. RCC (58.3%) and PNET (41.7%) in the IC vs. DOC groups. In conclusion, patients with vPNET meeting DOC criteria show greater similarity to sPNET. We suggest performing genetic testing, rather than solely using clinical criteria, for establishing the diagnosis of VHL.

Von Hippel-Lindau Syndrome: Medical Syndrome or Surgical Syndrome? A Surgical Perspective

Von Hippel-Lindau syndrome (VHL) is an autosomal dominant disease caused by a genetic aberration of the tumor suppressor gene VHL and characterized by multi-organ tumors. The most common neoplasm is retinal or cerebral hemangioblastoma, although spinal hemangioblastomas, Renal Clear Cell Carcinoma (RCCC), pheochromocytomas (Pheo), paragangliomas, Pancreatic Neuroendocrine Tumors (PNETs), cystadenomas of the epididymis, and tumors of the lymphatic sac can also be found. Neurological complications from retinal or CNS hemangioblastoma and metastases of RCCC are the most common causes of death. There is a strong association between pheochromocytoma and VHL syndrome, and pheochromocytoma is often a classic manifestation of the syndrome. RCCCs are often incidental and identified during other tests. Between 35 and 70% of patients with VHL have pancreatic cysts. These can manifest as simple cysts, serous cysto-adenomas, or PNETs with a risk of malignant degeneration or metastasis of no more than 8%. The objective of this retrospective study is to analyze abdominal manifestations of VHL from a surgical point of view.

Pancreatic Neuroendocrine Tumors: Molecular Mechanisms and Therapeutic Targets

Pancreatic neuroendocrine tumors (pNETs) are unique, slow-growing malignancies whose molecular pathogenesis is incompletely understood. With rising incidence of pNETs over the last four decades, larger and more comprehensive 'omic' analyses of patient tumors have led to a clearer picture of the pNET genomic landscape and transcriptional profiles for both primary and metastatic lesions. In pNET patients with advanced disease, those insights have guided the use of targeted therapies that inhibit activated mTOR and receptor tyrosine kinase (RTK) pathways or stimulate somatostatin receptor signaling. Such treatments have significantly benefited patients, but intrinsic or acquired drug resistance in the tumors remains a major problem that leaves few to no effective treatment options for advanced cases. This demands a better understanding of essential molecular and biological events underlying pNET growth, metastasis, and drug resistance. This review examines the known molecular alterations associated with pNET pathogenesis, identifying which changes may be drivers of the disease and, as such, relevant therapeutic targets. We also highlight areas that warrant further investigation at the biological level and discuss available model systems for pNET research. The paucity of pNET models has hampered research efforts over the years, although recently developed cell line, animal, patient-derived xenograft, and patient-derived organoid models have significantly expanded the available platforms for pNET investigations. Advancements in pNET research and understanding are expected to guide improved patient treatments.

Clinical presentation, genotype-phenotype correlations, and outcome of pancreatic neuroendocrine tumors in Von Hippel-Lindau syndrome

PURPOSE

Data regarding the clinical management and follow-up of pancreatic neuroendocrine tumors (PanNETs) associated with Von Hippel-Lindau (VHL) syndrome are limited. This study aimed to assess clinical presentation, genotype-phenotype correlations, treatment and prognosis of PanNETs in a series of VHL syndrome patients.

METHODS

Retrospective analysis of data of patients observed between 2005 and 2020.

RESULTS

Seventeen patients, including 12 probands and 5 relatives (mean age 30.8 ± 18.4; 7 males), were recruited. PanNETs were found in 13/17 patients (77.5%) at a median age of 37 years: 4/13 (30.7%) at the time of VHL diagnosis and 9 (69.3%) during follow up. Six (46.1%) PanNET patients underwent surgery, whereas seven were conservatively treated (mean tumor diameter: 40 ± 10.9 vs. 15 ± 5.3 mm respectively). Four patients (30.7%) had lymph node metastases and a mean tumor diameter significantly larger than the nonmetastatic PanNETs (44.2 ± 9.3 vs. 17.4 ± 7 mm, p = 0.00049, respectively). Five (83.3%) operated patients had stable disease after a median follow up of 3 years whereas one patient showed liver metastases. Six (85.7%) non-resected PanNETs were stable after a median follow-up of 2 years, whereas one patient developed a new small PanNET and a slight increase in diameter of a pre-existing PanNET. No correlation was found between the type of germline mutation and malignant behavior of PanNETs.

CONCLUSIONS

PanNETs are a common disease of the VHL syndrome and can be the presenting feature. Tumor size rather than genetic mutation is a prognostic factor of malignancy.

Phakomatoses and Endocrine Gland Tumors: Noteworthy and (Not so) Rare Associations

Phakomatoses encompass a group of rare genetic diseases, such as von Hippel-Lindau syndrome (VHL), neurofibromatosis type 1 (NF1), tuberous sclerosis complex (TSC) and Cowden syndrome (CS). These disorders are due to molecular abnormalities on the RAS-PI3K-Akt-mTOR pathway for NF1, TSC and CS, and to hypoxia sensing for VHL. Phakomatoses share some phenotypic traits such as neurological, ophthalmological and cutaneous features. Patients with these diseases are also predisposed to developing multiple endocrine tissue tumors, e.g., pheochromocytomas/paragangliomas are frequent in VHL and NF1. All forms of phakomatoses except CS may be associated with digestive neuroendocrine tumors. More rarely, thyroid cancer and pituitary or parathyroid adenomas have been reported. These susceptibilities are noteworthy, because their occurrence rate, prognosis and management differ slightly from the sporadic forms. The aim of this review is to summarize current knowledge on endocrine glands tumors associated with VHL, NF1, TSC, and CS, especially neuroendocrine tumors and pheochromocytomas/paragangliomas. We particularly detail recent advances concerning prognosis and management, especially parenchyma-sparing surgery and medical targeted therapies such as mTOR, MEK and HIF-2 α inhibitors, which have shown truly encouraging results.

VHL-Related Neuroendocrine Neoplasms And Beyond: An Israeli Specialized Center Real-Life Report

OBJECTIVE

Von Hippel-Lindau (VHL) syndrome is a rare and complex disease. In 1996, we described a 3 generation VHL 2A kindred with 11 mutation carriers. We aim to share our experience regarding the long-term follow-up of this family and the management of all our other VHL patients focusing on frequently encountered neuroendocrine neoplasms: pheochromocytoma/paraganglioma and pancreatic neuroendocrine neoplasms (PNEN).

METHODS

All VHL patients in follow-up at our tertiary center from 1980 to 2019 were identified. Clinical, laboratory, imaging, and therapeutic characteristics were retrospectively analyzed.

RESULTS

We identified 32 VHL patients in 16 different families, 7/16 were classified as VHL 2 subtype. In the previously described family, the 4 initially asymptomatic carriers developed a neuroendocrine tumor; 7 new children were born, 3 of them being mutation carriers; 2 patients died, 1 due to metastatic PNEN-related liver failure. Pheochromocytoma was frequent (22/32), bilateral (13/22;59%), often diagnosed in early childhood when active screening was timely performed, associated with paraganglioma in 5/22, rarely malignant (1/22), and recurred after surgery in some cases after more than 20 years. PNEN occurred in 8/32 patients (25%), and was metastatic in 3 patients. Surgery and palliative therapy allowed relatively satisfactory outcomes. Severe disabling morbidities due to central-nervous system and ophthalmologic hemangiomas, and other rare tumors as chondrosarcoma in 2 patients and polycythemia in 1 patient were observed.

CONCLUSION

A multidisciplinary approach and long-term follow-up is mandatory in VHL patients to manage the multiple debilitating morbidities and delay mortality in these complex patients.

Distinct Clinical Characteristics in Young-Onset Pancreatic Neuroendocrine Tumor

BACKGROUND

We aimed to study the effect of socioeconomic differences and molecular characteristics on survival in patients with young-onset pancreatic neuroendocrine tumors (YOPNET) and typical-onset PNET (TOPNET).

METHODS

We identified the patients with YOPNET (<50 years) and TOPNET (≥50 years) who underwent definitive surgery diagnosed between 2004 and 2016 using the National Cancer Database. We evaluated overall survival (OS) using the Kaplan-Meier and Cox regression methods before and after propensity score matching. A publicly available genomic dataset was used to compare mutation frequencies among the two groups.

RESULTS

A total of 6259 patients with PNET were included, of which 27% were YOPNET. Patients with YOPNET were more likely to be Black, Hispanic, female, and have private insurance versus patients with TOPNET (all p < 0.001). Patients with YOPNET had a lower comorbidity score, but higher stage and tumor size (all p < 0.001). YOPNET was associated with a greater improved OS than TOPNET before and after propensity score matching (p < 0.001). On multivariable analysis, this survival difference persisted for YOPNET as an independent prognostic factor (unmatched p = 0.008; matched p = 0.01). For genomic analysis, patients with YOPNET had a lower rate of multiple endocrine neoplasia type-1 (MEN-1) mutation than patients with TOPNET (26% vs. 56%, p < 0.001).

CONCLUSIONS

YOPNET represents a disease with distinct clinical features. Patients with YOPNET who underwent definitive surgery had better OS than patients with TOPNET despite having higher stage and tumor size. YOPNET also had lower rate of MEN-1 mutation.

Von Hippel-Lindau Disease: Current Challenges and Future Prospects

Understanding of molecular mechanisms of tumor growth has an increasing impact on the development of diagnostics and targeted therapy of human neoplasia. In this review, we summarize the current knowledge on molecular mechanisms and their clinical implications in von Hippel-Lindau (VHL) disease. This autosomal dominant tumor syndrome usually manifests in young adulthood and predisposes affected patients to the development of benign and malignant tumors of different organ systems mainly including the nervous system and internal organs. A consequent screening and timely preventive treatment of lesions are crucial for patients affected by VHL disease. Surgical indications and treatment have been evaluated and optimized over many years. In the last decade, pharmacological therapies have been evolving, but are largely still at an experimental stage. Effective pharmacological therapy as well as detection of biomarkers is based on the understanding of the molecular basis of disease. The molecular basis of von Hippel-Lindau disease is the loss of function of the VHL protein and subsequent accumulation of hypoxia-inducible factor with downstream effects on cellular metabolism and differentiation. Organs affected by VHL disease may develop frank tumors. More characteristically, however, they reveal multiple separate microscopic foci of neoplastic cell proliferation. The exact mechanisms of tumorigenesis in VHL disease are, however, still not entirely understood and knowledge on biomarkers and targeted therapy is scarce.

Molecular Signatures and Their Clinical Utility in Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors (PNETs) are classified based on their histologic differentiation and proliferative indices, which have been used extensively to determine prognosis. Advances in next-generation sequencing and other high-throughput techniques have allowed researchers to objectively explore tumor specimens and learn about the genetic alterations associated with malignant transformation in PNETs. As a result, targeted, pathway-specific therapies have been emerging for the treatment of unresectable and metastatic disease. As we continue to trial various pharmaceutical products, evidence from studies using multi-omics approaches indicates that clinical aggressiveness stratifies along other genotypic and phenotypic demarcations, as well. In this review, we explore the clinically relevant and potentially targetable molecular signatures of PNETs, their associated trials, and the overall differences in reported prognoses and responses to existing therapies.

The North American Neuroendocrine Tumor Society Consensus Paper on the Surgical Management of Pancreatic Neuroendocrine Tumors

This manuscript is the result of the North American Neuroendocrine Tumor Society consensus conference on the surgical management of pancreatic neuroendocrine tumors from July 19 to 20, 2018. The group reviewed a series of questions of specific interest to surgeons taking care of patients with pancreatic neuroendocrine tumors, and for each, the available literature was reviewed. What follows are these reviews for each question followed by recommendations of the panel.

von Hippel-Lindau Disease: an Update

Purpose of Review

In this review, we discuss the key molecular and clinical developments in VHL disease that have the potential to impact on the natural history of the disease and improve patient outcomes.

Recent Findings

Identifiable mutations in VHL underlie most cases of VHL and define clear genotype-phenotype correlations. Detailed clinical and molecular characterisation has allowed the implementation of lifelong screening programmes that have improved clinical outcomes. Functional characterisation of the VHL protein complex has revealed its role in oxygen sensing and the mechanisms of tumourigenesis that are now being exploited to develop novel therapies for VHL and renal cancer.

Summary

The molecular and cellular landscape of VHL-associated tumours is revealing new opportunities to modify the natural history of the disease and develop therapies. Drugs are now entering clinical trials and combined with improved clinical and molecular diagnosis, and lifelong surveillance programmes, further progress towards reducing the morbidity and mortality associated with VHL disease is anticipated.

Distinct genome-wide methylation patterns in sporadic and hereditary nonfunctioning pancreatic neuroendocrine tumors

BACKGROUND

Aberrant methylation is a known cause of cancer initiation and/or progression. There are scant data on the genome-wide methylation pattern of nonfunctioning pancreatic neuroendocrine tumors (NFPanNETs) and sporadic and hereditary NFPanNETs.

METHODS

Thirty-three tissue samples were analyzed: they included samples from sporadic (n = 9), von Hippel-Lindau (VHL)-related (n = 10), and multiple endocrine neoplasia type 1 (MEN1)-related NFPanNETs (n = 10) as well as normal islet cells (n = 4) for comparison. Genome-wide CpG methylation profiling was performed with the Infinium MethylationEPIC BeadChip assay and was analyzed with R-based tools.

RESULTS

In unsupervised hierarchical clustering, sporadic and MEN1-related NFPanNETs clustered together, and the VHL group was in a separate cluster. MEN1-related NFPanNETs had a higher rate of hypermethylated CpG sites in comparison with sporadic and VHL-related tumor groups. Differentially methylated region analysis confirmed the higher rate of hypermethylation in MEN1-related tumors. Moreover, in an integrated analysis of gene expression data for the same tumor samples, downregulated gene expression was found in most genes that were hypermethylated. In a CpG island methylator phenotype analysis, 3 genes were identified and confirmed to have downregulated gene expression: secreted frizzle-related protein 5 (SFRP5) in sporadic NFPanNETs and cell division cycle-associated 7-like (CDCA7L) and RNA binding motif 47 (RBM47) in MEN1-related NFPanNETs.

CONCLUSIONS

MEN1 NFPanNETs have a higher rate of geno me-wide hypermethylation than other NFPanNET subtypes. The similarity between the pathways enriched in a methylation analysis of known genes involved in NFPanNET tumorigenesis suggests a key role for aberrant methylation in the pathogenesis of NFPanNETs.

Neoplasms of the Neuroendocrine Pancreas: An Update in the Classification, Definition, and Molecular Genetic Advances

This review focuses on discussing the main modifications of the recently published 2017 WHO Classification of Neoplasms of the Neuroendocrine Pancreas (panNEN). Recent updates separate pancreatic neuroendocrine tumors into 2 broad categories: well-differentiated pancreatic neuroendocrine tumors (panNET) and poorly differentiated pancreatic neuroendocrine carcinoma (panNEC), and incorporates a new subcategory of "well-differentiated high-grade NET (G3)" to the well-differentiated NET category. This new classification algorithm aims to improve the prediction of clinical outcomes and survival and help clinicians select better therapeutic strategies for patient care and management. In addition, these neuroendocrine neoplasms are capable of producing large quantity of hormones leading to clinical hormone hypersecretion syndromes. These functioning tumors include, insulinomas, glucagonomas, somatostatinomas, gastrinomas, VIPomas, serotonin-producing tumors, and ACTH-producing tumors. Although most panNENs arise as sporadic diseases, a subset of these heterogeneous tumors present as parts on inherited genetic syndromes, such as multiple endocrine neoplasia type 1, von Hippel-Lindau, neurofibromatosis type 1, tuberous sclerosis, and glucagon cell hyperplasia and neoplasia syndromes. Characteristic clinical and morphologic findings for certain functioning and syndromic panNENs should alert both pathologists and clinicians as appropriate patient management and possible genetic counseling may be necessary.

Transcriptional alterations in hereditary and sporadic nonfunctioning pancreatic neuroendocrine tumors according to genotype

BACKGROUND

Nonfunctioning pancreatic neuroendocrine tumors (NFPanNETs) may be sporadic or inherited because of germline mutations associated with von Hippel-Lindau disease (VHL) or multiple endocrine neoplasia type 1 (MEN1). The clinical behavior of NFPanNETs is difficult to predict, even in tumors of the same stage and grade. The authors analyzed genotype-specific patterns of transcriptional messenger RNA (mRNA) levels of NFPanNETs to understand the molecular features that determine PanNET phenotype.

METHODS

Thirty-two samples were included for genome-wide mRNA gene expression analysis (9 VHL-associated, 10 MEN1-associated, and 9 sporadic NFPanNETs and 4 purified normal islet cell [NIC] samples). Validation of genes was performed by real-time polymerase chain reaction analysis and immunohistochemistry. Gene expression profiles were analyzed by tumor genotype, and pathway analysis was curated.

RESULTS

Consensus clustering of mRNA expression revealed separate clustering of NICs, VHL-associated NFPanNETs, and MEN1-associated NFPanNETs; whereas some sporadic tumors clustered with MEN1. Four of 5 MEN1-like sporadic PanNET subtypes had loss of heterozygosity at the MEN1 gene locus. Pathway analysis demonstrated subtype-specific pathway activation, comprising angiogenesis and immune response in VHL; neuronal development in MEN1; protein ubiquitination in the new MEN1/sporadic subtype; and cytokinesis and cilium/microtubule development in sporadic NFPanNETs. Among many genes, platelet-derived growth factor receptor β (PDGFRB), lymphoid enhancer-binding factor-1 (Lef-1), cyclin-dependent kinase 4 (CDK4), and CDK6 were upregulated in VHL or MEN1 NFPanNETs, providing potential subtype-specific treatment targets.

CONCLUSIONS

Distinct mRNA expression patterns were identified in sporadic-associated, VHL-associated, and MEN1-associated NFPanNETs. The current results uncover new pathways involved in NFPanNETs that are subtype-specific and provide potential new diagnostic or therapeutic targets based on tumor subtype. Cancer 2018;124:636-47. © 2017 American Cancer Society.

When should genetic testing be performed in patients with neuroendocrine tumours?

Neuroendocrine tumours (NETs) are a heterogenous group of tumours arising from neuroendocrine cells in several sites around the body. They include tumours of the gastroenteropancreatic system, phaeochromocytoma and paraganglioma and medullary thyroid cancer. In recent years, it has become increasingly apparent that a number of these tumours arise as a result of germline genetic mutations and are inherited in an autosomal dominant pattern. The number of genes implicated is increasing rapidly. Identifying which patients are likely to have a germline mutation enables clinicians to counsel patients adequately about their future disease risk, and allows for earlier detection of at-risk patients through family screening. The institution of screening and surveillance programmes may in turn lead to a major shift in presentation patterns for some of these tumours. In this review, we examine the features which may lead a clinician to suspect that a patient may have an inherited cause of a NET and we outline which underlying conditions should be suspected. We also discuss what type of screening may be appropriate in a variety of situations.

Acinar Cell Cystadenoma - a Rarity in Advanced von Hippel-Lindau Disease: A Case Report

Background

Von Hippel-Lindau (VHL) disease may occur at various localisations which can be both intra- and extrapancreatic as well as challenging to diagnose by medical imaging.

Case Report

A positron emission tomography/magnetic resonance imaging in a 40-year-old woman was performed to monitor a haemangioblastoma. Additionally, it showed findings which were considered to be a pancreatic neuroendocrine tumour (pNET) and retroumbilical metastasis. The suspected metastasis was laparoscopically resected; however, pathological evaluation did not lead to a clear categorisation. Consequently, the pancreatic head was resected in which a pNET and various acinar cell cystadenomas were found.

Conclusion

Diagnostic and therapy of advanced VHL disease can be difficult; if in doubt, a surgical approach may establish clarity.

Pancreatic neuroendocrine tumor with complete replacement of the pancreas by serous cystic neoplasms in a patient with von Hippel-Lindau disease: a case report

Background

von Hippel-Lindau disease is a dominantly inherited multi-system syndrome with neoplastic hallmarks. Pancreatic lesions associated with von Hippel-Lindau include serous cystic neoplasms, simple cysts, and neuroendocrine tumors. The combination of pancreatic neuroendocrine tumors and serous cystic neoplasms is relatively rare, and the surgical treatment of these lesions must consider both preservation of pancreatic function and oncological clearance. We report a patient with von Hippel-Lindau disease successfully treated with pancreas-sparing resection of a pancreatic neuroendocrine tumor where the pancreas had been completely replaced by serous cystic neoplasms, in which pancreatic function was preserved.

Case presentation

A 39-year-old female with von Hippel-Lindau disease was referred to our institution for treatment of a pancreatic neuroendocrine tumor. Abdominal computed tomography demonstrated a well-enhanced mass, 4 cm in diameter in the tail of the pancreas, and two multilocular tumors with several calcifications, 5 cm in diameter, in the head of the pancreas. There was complete replacement of the pancreas by multiple cystic lesions with diameters ranging from 1 to 3 cm. Magnetic resonance cholangiopancreatography showed innumerable cystic lesions on the whole pancreas and no detectable main pancreatic duct. Endoscopic ultrasound-guided fine-needle aspiration of the mass in the pancreatic tail showed characteristic features of a neuroendocrine tumor. A diagnosis of pancreatic neuroendocrine tumor in the tail of the pancreas and mixed-type serous cystic neoplasms replacing the whole pancreas was made and she underwent distal pancreatectomy while avoiding total pancreatectomy. The stump of the pancreas was sutured as firm as possible using a fish-mouth closure. The patient made a good recovery and was discharged on postoperative day 9. She is currently alive and well with no symptoms of endocrine or exocrine pancreatic insufficiency 8 months after surgery.

Conclusions

A pancreas-sparing resection should be considered for patients with pancreatic neuroendocrine tumors and complete cystic replacement of the pancreas to preserve quality of life after surgery.

Clinical Profile of Pancreatic Cystic Lesions in von Hippel-Lindau Disease: A Series of 48 Patients Seen at a Tertiary Institution

OBJECTIVES

Little is known about the association between pancreatic cystic lesions (PCLs) with von Hippel-Lindau disease (VHLD). In this study, we describe the clinical presentation, type of PCLs, and risk for malignancy in PCLs in VHLD.

METHODS

Patients given a diagnosis of both VHLD and PCLs were identified from electronic medical records at Mayo Clinic, Rochester, MN, from January 1, 2000, to January 1, 2016. Various demographic, clinical, and radiologic variables were recorded.

RESULTS

Forty-eight patients were identified with PCLs and VHLD. Most were female (73%), and mean (standard deviation) age was 35.9 (14.2) years. Most (92%) were asymptomatic. PCLs included simple cysts (n = 34, 69%), serous cystadenoma (n = 14, 29%), branch duct intraductal papillary neoplasm (n = 5, 10%), and cystic neuroendocrine tumors (n = 2, 4%). Eight (19%) had mixed PCLs. Cyst aspiration was performed in 8 (53%) patients who underwent EUS, and all were negative for malignancy. At a median follow-up of 84 months, no PCL-associated cancers were seen.

CONCLUSIONS

Simple cyst is the most common type of PCL found in VHL disease; however, other PCLs were also seen with no malignancy potential. Branch duct intraductal papillary mucinous neoplasms were present in 10%, and this association was not hitherto reported.

Single-stage laparoscopic adrenalectomy for pheochromocytoma and enucleation of a pancreatic neuroendocrine tumor in Von Hippel-Lindau disease: A case report

Von Hippel-Lindau (VHL) disease is an inherited syndrome with autosomal-dominant transmission, characterized by central nervous system and retinal hemangioblastomas, visceral cysts and tumors. Optimal surgical treatment, including its timing, remains a controversial topic. The present study reports the case of a 67-year-old female patient with adrenal and pancreatic manifestations of VHL. A laparoscopic cortex-sparing left adrenalectomy for a 4-cm pheochromocytoma and pancreatic enucleation for pancreatic polypeptidoma of the pancreas tail were performed during the same operative procedure. The total operative time was 240 min. There were no operative complications, and the surgery was completed laparoscopically with minimal blood loss. A prolonged hospital stay was necessary to treat a grade C postoperative pancreatic fistula. The histopathological result was an adrenal pheochromocytoma and a well-differentiated neuroendocrine tumor, secreting pancreatic polypeptides. In conclusion, organ-sparing laparoscopic surgery is an important option for treating simultaneous lesions in several abdominal solid viscera, such as VHL disease, and the present case study represents, to the best of the authors' knowledge, the first report of single-stage laparoscopic adrenalectomy and pancreatic tumor enucleation.

Guidelines for the management of neuroendocrine tumours by the Brazilian gastrointestinal tumour group

Neuroendocrine tumours are a heterogeneous group of diseases with a significant variety of diagnostic tests and treatment modalities. Guidelines were developed by North American and European groups to recommend their best management. However, local particularities and relativisms found worldwide led us to create Brazilian guidelines. Our consensus considered the best feasible strategies in an environment involving more limited resources. We believe that our recommendations may be extended to other countries with similar economic standards.

Von Hippel-Lindau disease involving pancreas and biliary system: A rare case report

RATIONALE

Von Hippel-Lindau (VHL) disease is a rare inherited, autosomal-dominant syndrome caused by heterozygous germline mutations in the VHL gene. VHL patients are prone to develop benign and malignant tumors and cysts in multiple organ systems involving kidneys, pancreas and central nervous system (CNS). The varied and complex clinical manifestations and radiological findings of VHL are of interest.

PATIENT CONCERNS

We report a 38-year-old woman with a ten-year history of VHL disease involving both pancreas and biliary system. To the best of our knowledge, direct involvement of the biliary system in VHL disease has never been reported.

DIAGNOSES

The diagnosis was established via computed tomography scan and was confirmed by genetic testing.

INTERVENTIONS

The patient chose to receive conservative treatment and was followed up by magnetic resonance cholangiopancreatography and magnetic resonance imaging examination.

OUTCOMES

Renal angiomas and cysts were found during follow-up and there were no evidence of malignant change of the pancreas and biliary system.

LESSONS

We described the first case of VHL-associated choledochal cysts and may present new visceral manifestations of VHL disease. Gastroenterologists should be aware of the clinical presentations of this rare disease for early detection of its life-threatening manifestations.

Pancreatic Tumor Growth Prediction With Elastic-Growth Decomposition, Image-Derived Motion, and FDM-FEM Coupling

Pancreatic neuroendocrine tumors are abnormal growths of hormone-producing cells in the pancreas. Unlike the brain which is protected by the skull, the pancreas can be significantly deformed by its surrounding organs. Consequently, the tumor shape differences observable from images at different time points arise from both tumor growth and pancreatic motion, and tumor growth model personalization may be compromised if such motion is ignored. Therefore, we incorporate pancreatic motion information derived from deformable image registration in model personalization. For more accurate mechanical interactions between tumor growth and pancreatic motion, elastic-growth decomposition is used with a hyperelastic constitutive law to model the mass effect, which allows growth modeling while conserving the mechanical properties. Furthermore, a way of coupling the finite difference method and the finite element method is proposed to greatly reduce the computation time. With both 2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomographic and contrast-enhanced computed tomographic images, functional, structural, and motion data are combined for a patient-specific model. Experiments on synthetic and clinical data show the importance of image-derived motion on estimating pathophysiologically plausible mechanical properties and the promising performance of our framework. From seven patient data sets, the recall, precision, Dice coefficient, relative volume difference, and average surface distance between the personalized tumor growth simulations and the measurements were 83.2 ±8.8%, 86.9 ±8.3%, 84.4 ±4.0%, 13.9 ±9.8%, and 0.6 ±0.1 mm, respectively.

18F-FDG PET/CT Volumetric Parameters are Associated with Tumor Grade and Metastasis in Pancreatic Neuroendocrine Tumors in von Hippel-Lindau Disease

BACKGROUND

Approximately 8-17 % of patients with von Hippel-Lindau (VHL) syndrome develop pancreatic neuroendocrine tumors (PNETs), with 11-20 % developing metastases. Tumor grade is predictive of prognosis.

OBJECTIVE

The aim of this study was to determine if preoperative metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were associated with metastatic disease and tumor grade.

METHODS

Sixty-two patients with VHL-associated PNETs prospectively underwent ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT). MTV, TLG, and maximum standardized uptake value (SUV_max) were measured using a semi-automatic method. Surgically resected PNETs were classified according to 2010 World Health Organization tumor grade classification. MTV, TLG, and SUV_max were analyzed by metastatic disease and tumor grade using the Mann-Whitney test.

RESULTS

A total of 88 PNETs were identified by CT and ¹⁸F-FDG PET/CT, 10 of which were non-FDG-avid. Histologic grading was available for 20 surgical patients. Patients with metastatic PNETs had a higher TLG (median 25.9 vs. 7.7 mean SUV [SUV_mean]*mL; p = 0.0092) compared with patients without metastasis, while patients with grade 2 PNETs had a higher MTV (median 6.9 vs. 2.6 mL; p = 0.034) and TLG (median 41.2 vs. 13.1 SUV_mean*mL; p = 0.0035) compared with patients with grade 1 PNETs. No difference in tumor size or SUV_max was observed between the groups.

CONCLUSIONS

Patients with metastatic PNETs have a higher TLG compared with patients without metastasis. Grade 2 PNETs have a higher MTV and TLG compared with grade 1 PNETs. Tumor size and SUV_max were not associated with grade. Volumetric parameters on ¹⁸F-FDG PET/CT may be useful in detecting higher grade PNETs with a higher malignant potential that may need surgical intervention.

Mixed serous neuroendocrine neoplasm of the pancreas: Case report and literature review

INTRODUCTION

The aim of this study was to report a new case of mixed serous neuroendocrine neoplasm (MSNN) and review the literature concerning this type of lesion, which was added to the World Health Organization classification of pancreatic tumors in 2010.

RESULTS

A 73-year-old woman presented with a pancreatic mass. The lesion was an intriguing combination of serous cystic neoplasm (SCN) and pancreatic neuroendocrine tumor (PanNET), in which the PanNET component grew into the wall of the serous oligocystic adenoma. We searched different databases for studies that had investigated MSNN. A total of 15 patients (age, 28-78), including the patient in the present study, were evaluated. We discuss these cases in detail especially regarding morphology and pathology; our case was the only one involving a collision type combination.

CONCLUSION

Although MSNN is recognized as a variant of SCN, it is quite different from SCN or PanNET. A new morphological analysis of MSNN may help in elucidating its histogenesis and prognosis.

Management of pancreatic gastrinoma associated with Von Hippel-Lindau disease: a case report

BACKGROUND

Pancreatic neuroendocrine tumors (PNET) are a heterogeneous group and constitute 1.3% of all pancreatic tumors. Approximately 10% of these occur in the context of hereditary syndromes, such as VHL disease.

CASE REPORT

We report a case of a female patient of 37 years diagnosed VHL and intervened on several occasions by cerebral hemangioblastoma and renal carcinomas. During its follow-up she was diagnosed 2 gastrinomas functioning under 2 cm were enucleated. Later developed new PNET and underwent a total duodenopancreatectomy without pyloric preservation.

DISCUSSION

The management of PNET in VHL is difficult due to the association of multiple tumors in different organs and the morbidity and mortality associated with the surgery of the pancreas. Management must be individualized for each patient, based on the ability to produce hormones and present symptoms, the size and location, and in the context of other tumors that usually present in these patients.

von Hippel-Lindau Disease: Review of Genetics and Imaging

von Hippel-Lindau (VHL) disease is an autosomal-dominant, hereditary, multisystem neoplasia syndrome with increased susceptibility to several benign and malignant tumors. VHL occurs in about 1 in 36,000 live births and is associated with germline mutation of the VHL tumor suppressor gene on the short arm of chromosome 3. VHL disease exhibits diverse genotype and phenotype correlations, exhibits variable intrafamilial and interfamilial expressivity, and can manifest with benign and malignant tumors of the central nervous system, kidneys, adrenals, pancreas, and reproductive organs. Imaging and management of this entity are therefore multidisciplinary. An overview of VHL disease is presented.

Pancreatic neuroendocrine tumors: Challenges in an underestimated disease

Pancreatic neuroendocrine tumours (PanNETs) are considered a relatively unusual oncologic entity. Due to its relative good prognosis, surgery remains the goal standard therapy not only in localized disease but also in the setting of locally or metastatic disease. Most of the patients are diagnosed in metastatic scenario, where multidisciplinary approach based on surgery, chemotherapies, liver-directed and/or molecular targeted therapies are commonly used. Owing to a deeper molecular knowledge of this disease, these targeted therapies are nowadays widely implemented, being the likely discovery of predictive biomarkers that would allow its use in other settings. This review is focused on describing the different classifications, etiology, prognostic biomarkers and multidisciplinary approaches that are typically used in PanNET.

Full laparoscopic total pancreatectomy with and without spleen and pylorus preservation: a feasibility report

BACKGROUND/PURPOSE

Laparoscopic pancreatic surgery is gaining acceptance and clear advantages have been demonstrated in distal resection. Total pancreaticoduodenectomy (TPD) combines the operative steps of distal pancreatectomy and pancreaticoduodenectomy, but facilitates reconstruction and lowers the risk of common complications by avoiding the need for a pancreatic anastomosis. The aim of this report is to analyse the feasibility of laparoscopic total pancreaticoduodenectomy, with and without spleen and pylorus preservation.

METHODS

Two patients underwent laparoscopic TPD for pancreatic intraductal mucinous neoplasm and endocrine tumors. Total splenopancreaticoduodenectomy (TSP) and pylorus- and spleen-preserving total pancreaticoduodenectomy (PSPTP) were performed.

RESULTS

The two procedures were successfully completed laparoscopically. PSPTP was more time-consuming (420 vs. 360 min) and had an increased risk of hemorrhage (600 vs. 200 ml) compared with TSP. After both procedures, the postoperative outcome was uneventful and the postoperative length of hospital stay was 8 days.

CONCLUSIONS

This report confirms the feasibility of full laparoscopic TPD, and presents the first full laparoscopic pylorus- and spleen-preservation technique with conservation of the splenic vessels, without robotic assistance. No conclusions can be drawn from this report, but it shows that the laparoscopic approach provides visual magnification, improved exposure, and delicate manipulation of tissues, which may reproduce the clear advantages of laparoscopic distal pancreatectomy.

Laparoscopic Pylorus- and Spleen-Preserving Duodenopancreatectomy for a Multifocal Neuroendocrine Tumor

Background

In contrast to laparoscopic left pancreatic resection, laparoscopic total duodenopancreatectomy is a procedure that has not been standardized until now. It is not only the complexity that limits such a procedure but also its rare indication. The following article demonstrates the technical aspects of laparoscopic pylorus- and spleen-preserving duodenopancreatectomy.

Case Report

The indication for intervention in the underlying case was a patient diagnosed with a multiple endocrine neoplasia (MEN) I syndrome and a multifocal neuroendocrine tumor (NET) infiltrating the duodenum and the pancreas. The patient was post median laparotomy which was necessary after jejunal perforation due to a peptic ulcer. The resection was carried out entirely laparoscopically, and the reconstruction, which included a biliodigestive anastomosis and a gastroenterostomy, was carried out by means of a median upper abdomen laparotomy of 7 cm in length through which the resected specimen was also removed. The total operative time was 391 min. The blood loss accounted for 250 ml. The postoperative course was uneventful, and the patient was discharged on the eighth postoperative day.

Conclusion

Laparoscopic pancreatectomy is a treatment option in carefully selected indications. The complexity of the operation demands a high level of expertise in the surgical team.

Long-term Prognosis of Resected Pancreatic Neuroendocrine Tumors in von Hippel-Lindau Disease Is Favorable and Not Influenced by Small Tumors Left in Place

BACKGROUND

Management of pancreatic neuroendocrine tumors (PNETs) associated with von Hippel-Lindau disease (VHL) is challenging because of the malignant potential and difficulty in predicting prognosis.

OBJECTIVE

Compare the long-term outcome of resected VHL-PNET and sporadic PNET.

METHODS

Data of all patients with VHL (n = 23) operated on for nonmetastatic PNET were reviewed. Patient characteristics and recurrence-free survival rates were compared with those in patients operated on for sporadic PNET, matched for tumor size, stage, and Ki-67 index.

RESULTS

Patients in both groups had similar demographic characteristics, except that patients with VHL were younger (36 vs 56 years, P < 0.0001). Median tumor size was 30 mm. Median Ki-67 index was 3% and 4% in the VHL and sporadic groups (P = 0.95), respectively, and lymph node metastases were present in 43% and 30% of cases, respectively (P = 0.45). Sixteen (70%) patients with VHL had multiple PNET; lesions less than 15 mm were left in place in 11 patients. Median postoperative follow-up was 107 months (interquartile range, 57-124 months) and 71 months (interquartile range, 58-131 months) in the VHL and control groups, respectively. Median recurrence-free survival could not have been estimated in the VHL group due to the low number of events (hazard ratio, 5.6; 95% confidence interval, 1.4-22.6; P = 0.013). Five patients with VHL died (3 from VHL-related tumors including 1 from PNET), whereas only one control patient died due to unrelated causes.

CONCLUSIONS

The long-term outcome of resected VHL-PNET is better than that of sporadic PNET. PNET less than 15 mm left in place did not progress. A parenchyma-sparing surgical strategy seems appropriate in patients with VHL-PNET, who may develop more life-threatening tumors of other organs.

Clinical features of pancreatic involvement in von Hippel-Lindau disease: a retrospective study of 55 cases in a single center

BACKGROUND

von Hippel-Lindau (VHL) disease is an autosomal dominant disorder characterized by the development of multiple tumors in the central nervous system and visceral organs. In this study, we describe clinical features of pancreatic involvement in VHL disease, of which there have been few reported studies to date.

METHODS

We reviewed medical records of 63 VHL patients, diagnosed at Asan Medical Center between January 1995 and December 2013. Demographic, genetic, and radiologic features, and the clinical course of VHL patients with pancreatic involvement were retrospectively analyzed.

RESULTS

Among the 63 VHL patients, 55 (87.4%) had VHL-associated pancreatic lesions (male: female, 31:24; median age at onset, 33 years; range, 12-67 years). These presented as single simple cysts (n = 5, 9.1%), multiple simple cysts (n = 14, 25.5%), serous cystadenoma (n = 29, 52.7%), or neuroendocrine tumors (NETs) (n = 17, 30.9%). Genetic tests were performed on 35 of the 55 patients (63.6%) and VHL gene mutations were observed in 28 of them (80%). Of the 55 patients, 11 received surgical treatment, 2 received endoscopic ultrasonography-guided ethanol ablation therapy as local treatment for NET, and 42 patients were followed regularly without intervention (20%, 3.6%, and 76.4%, respectively).

CONCLUSION

Pancreatic involvement in VHL disease is common, with a prevalence of 87.4%. Serial screening imaging studies for the early detection of VHL-associated NET are necessary in individuals at risk of VHL disease. A large-scale epidemiological study of VHL disease is needed to examine the natural course of the disease and the prognosis for pancreatic involvement.

Pancreatic Tumor Growth Prediction with Multiplicative Growth and Image-Derived Motion

Pancreatic neuroendocrine tumors are abnormal growths of hormone-producing cells in the pancreas. Different from the brain in the skull, the pancreas in the abdomen can be largely deformed by the body posture and the surrounding organs. In consequence, both tumor growth and pancreatic motion attribute to the tumor shape difference observable from images. As images at different time points are used to personalize the tumor growth model, the prediction accuracy may be reduced if such motion is ignored. Therefore, we incorporate the image-derived pancreatic motion to tumor growth personalization. For realistic mechanical interactions, the multiplicative growth decomposition is used with a hyperelastic constitutive law to model tumor mass effect, which allows growth modeling without compromising the mechanical accuracy. With also the FDG-PET and contrast-enhanced CT images, the functional, structural, and motion data are combined for a more patient-specific model. Experiments on synthetic and clinical data show the importance of image-derived motion on estimating physiologically plausible mechanical properties and the promising performance of our framework. From six patient data sets, the recall, precision, Dice coefficient, relative volume difference, and average surface distance were 89.8 ± 3.5%, 85.6 ± 7.5%, 87.4 ± 3.6%, 9.7 ± 7.2%, and 0.6 ± 0.2 mm, respectively.

Management of von hippel-lindau disease: an interdisciplinary review

Von Hippel-Lindau (VHL) disease is an autosomal dominantly inherited tumour predisposition syndrome with an incidence of 1:36,000 newborns, the estimated prevalence in Europe is about 1-9/100,000. It is associated with an increased risk of developing various benign and malignant tumours, thus affecting multiple organs at different time points in the life of a patient. Disease severity and diversity as well as age at first symptoms vary considerably, and diagnostic delay due to failure of recognition is a relevant issue. The identification of a disease-causing VHL germline mutation subsequently allows family members at risk to undergo predictive genetic testing after genetic counselling. Clinical management of patients and families should optimally be offered as an interdisciplinary approach. Prophylactic screening programs are a cornerstone of care, and have markedly improved median overall survival of affected patients. The aim of this review is to give an overview of the heterogeneous manifestations of the VHL syndrome and to highlight the diagnostic and therapeutic challenges characteristic for this orphan disease. A comprehensive update of the underlying genetic and molecular principles is additionally provided. We also describe how the St. Gallen VHL multidisciplinary group is organised as an example of interdisciplinary cooperation in a tertiary hospital in Switzerland.

Obstructive jaundice due to von Hippel-Lindau disease-associated pancreatic lesions: A case report

von Hippel-Lindau (VHL) disease is an autosomal dominantly inherited neoplastic syndrome that may lead to pancreatic masses and obstructive jaundice. The present study describes the case of a 20-year-old male who suffered from obstructive jaundice due to VHL disease-associated pancreatic lesions whose primary symptom was dizziness, followed by the appearance of jaundice. Since the excision of the renal cell carcinomas was not possible, the patient also refused surgery to resect the pancreatic head mass. A metallic stent was placed at the stenosis site of the common bile duct. Percutaneous transhepatic cholangiography (PTCD) surgery was later performed following complete blockage of the stent, however, to date, the patient continues to rely on PTCD. VHL disease-associated pancreatic lesions are rarely the direct cause of mortality, however, obstructive jaundice due to these lesions may be lethal. Therefore, the treatment of patients with incurable renal or central nervous system tumors and obstructive jaundice presents a problem.

Pancreatic involvement in Japanese patients with von Hippel-Lindau disease: results of a nationwide survey

BACKGROUND

The frequency and prognosis of pancreatic endocrine tumors (PNET)/pancreatic cystic tumors (PCT) in Japanese patients with von Hippel-Lindau disease (VHL) are still open to question.

METHODS

We conducted the first nationwide epidemiological study of VHL disease in Japan to elucidate this question. Data on 377 VHL patients (PNET, 53; PCT, 152) were reported, and then their clinical characteristics were analyzed.

RESULTS

PNET was found in 14.1 % and PCT in 40.3 %; 4.5 % had both. The onset of PNET and PCT mostly occurred at 30-39 years of age (median ages, 34 and 33 years, respectively). Metastasis was observed in 7.5 % of PNET patients at diagnosis, and 64.2 % underwent surgery including enucleation, partial and total pancreatectomy, and bypass surgery. Two patients received non-surgical therapies. No PNET-related deaths were observed. In PCT patients, no metastasis was observed at diagnosis, and 9.2 % underwent surgery or drainage. According to the classification system without or with adrenal pheochromocytoma, the VHL patients studied herein were subdivided into 313 (83 %) with VHL type 1 and 64 (17 %) with VHL type 2; 29 (9.3 %) and 24 (37.5 %) patients had PNET with VHL type 1 and 2, suggesting that patients with VHL type 2 were significantly more related to PNET than those with VHL type 1 (P < 0.01).

CONCLUSIONS

This study showed no significant difference in the epidemiology of pancreatic involvement between Japanese and non-Japanese VHL patients. Concerning the prognosis, follow-up study is needed.

Prospective natural history study of central nervous system hemangioblastomas in von Hippel-Lindau disease

OBJECT

The tumors most frequently associated with von Hippel-Lindau (VHL) disease are hemangioblastomas. While they are associated with significant neurological impairment and mortality, their natural history and optimal management have not been fully defined.

METHODS

Patients with VHL were enrolled in a prospective study designed to define the natural history of CNS hemangioblastomas. In the present analysis, serial imaging, laboratory, genetic, and clinical data were evaluated in those with at least 2 years of follow-up data.

RESULTS

At study entrance 225 patients (111 males, 114 females) harbored 1921 CNS hemangioblastomas in the supratentorial compartment (21 tumors [1%]), cerebellum (865 [45%]), brainstem (129 [7%]), spinal cord (689 [36%]), cauda equina (212 [11%]), and nerve roots (5 [0.3%]; follow-up 15,819 hemangioblastoma-years). Increased tumor burden was associated with partial deletions in the VHL gene (p = 0.005) and male sex (p = 0.002). Hemangioblastoma development (median 0.3 new tumors/year) was associated with younger age (p < 0.0001) and more tumors at study entrance (p < 0.0001). While 1278 hemangioblastomas (51%) did not grow, 1227 hemangioblastomas (49%) grew in a saltatory (886 [72%]), linear (76 [6%]), or exponential (264 [22%]) pattern. Faster tumor growth was associated with male sex (p = 0.001), symptomatic tumors (p < 0.0001), and tumors associated with cysts (p < 0.0001). Location-dependent tumor size was the primary predictor of eventual symptom formation (159 symptomatic tumors [6.3%]; area under the curve > 0.9).

CONCLUSIONS

Central nervous system hemangioblastoma burden in VHL is associated with partial germline deletions and male sex. Unpredictable growth of hemangioblastomas compromises assessment of nonsurgical therapies. The judicious treatment of symptom-producing hemangioblastomas, while avoiding unnecessary treatment of asymptomatic tumors that may not progress, can provide clinical stability.

A novel mutation in the von hippel-lindau tumor suppressor gene identified in a patient presenting with gestational diabetes mellitus

BACKGROUND

Von Hippel-Lindau (VHL) disease is an autosomal dominantly inherited, multisystemic tumor syndrome caused by mutations in the VHL gene. To date, more than 1,000 germline and somatic mutations of the VHL gene have been reported. We present a novel mutation in the VHL tumor suppressor gene that presented with gestational diabetes mellitus.

METHODS

A 30-year-old woman presented with gestational diabetes mellitus. She sequentially showed multiple pancreatic cysts, spinal cord hemangioblastoma, cerebellar hemangioblastoma, and clear cell type renal cell carcinomas. Also, her father and brother had brain hemangioblastomas. Each of the three exons of the VHL gene was individually amplified by polymerase chain reaction and direct sequencing was performed using an ABI 3730 DNA analyzer.

RESULTS

DNA sequence analysis to determine the presence of VHL mutation in her family revealed del291C, a novel frameshift mutation.

CONCLUSION

We found a novel mutation in the VHL tumor suppressor gene that presented with gestational diabetes mellitus.

Digestive neuroendocrine tumors (DNET): the era of targeted therapies

Neuroendocrine tumors (NETs) are a heterogeneous group of malignancies. Therapeutic options depend on location of the primitive tumor, its expandability, its hormonal symptoms and its differentiation. Though relatively rare, with an increasing incidence and a high prevalence digestive neuroendocrine tumors (DNETs) are ranked just behind colorectal cancer as the most common digestive cancers in developed countries. Three main therapeutic axes have been individualized in the field of well-differentiated DNETs (corresponding to grades 1 and 2 of new WHO classification 2010), firstly, antitumor activity of somatostatin analogs, particularly in slowly progressive metastatic DNETs with limited hepatic invasion, secondly, targeting angiogenesis in these hypervascular tumors and thirdly targeting the mTOR pathway involved in DNETs carcinogenesis. As a consequence of two major randomized phase III trials in 2011, sunitinib and everolimus have been considered as new therapeutic options for well-differentiated, advanced and progressive pancreatic NETs. For everolimus, another phase III study, although non-significant with the chosen criteria, showed effectiveness notably against small intestine NETs. These targeted therapies are new therapeutic weapons in management of well-differentiated DNETs, but its exact role in care strategy, in comparison with other treatments (somatostatin analogs, chemo-embolization, chemotherapy...) deserves to be precise in the future.

Nervous system involvement in von Hippel-Lindau disease: pathology and mechanisms

Patients with von Hippel-Lindau disease carry a germline mutation of the Von Hippel-Lindau (VHL) tumor-suppressor gene. We discuss the molecular consequences of loss of VHL gene function and their impact on the nervous system. Dysfunction of the VHL protein causes accumulation and activation of hypoxia inducible factor (HIF) which can be demonstrated in earliest stages of tumorigenesis and is followed by expression of VEGF, erythropoietin, nitric oxide synthase and glucose transporter 1 in VHL-deficient tumor cells. HIF-independent functions of VHL, epigenetic inactivation of VHL, pVHL proteostasis, and links between loss of VHL function and developmental arrest are also described. A most intriguing feature in VHL disease is the occurrence of primary hemangioblastic tumors in the nervous system, the origin of which has not yet been entirely clarified, and current hypotheses are discussed. Endolymphatic sac tumors may extend into the brain, but originally arise from proliferation of endolymphatic duct/sac epithelium; the exact nature of the proliferating epithelial cell, however, also has remained unclear, as well as the question why tumors almost consistently develop in the intraosseous portion of the endolymphatic sac/duct only. The epitheloid clear cell morphology of both advanced hemangioblastoma and renal clear cell carcinoma can make the differential diagnosis challenging, recent developments in immunohistochemical differentiation are discussed. Finally, metastasis to brain may not only be caused by renal carcinoma, but may derive from VHL disease-associated pheochromocytoma/paraganglioma, or pancreatic neuroendocrine tumor.

The metabolic basis of kidney cancer

Kidney cancer is not a single disease; it is made up of a number of different types of cancer that occur in the kidney. Each of these different types of kidney cancer can have a different histology, have a different clinical course, can respond differently to therapy and is caused by a different gene. Kidney cancer is essentially a metabolic disease; each of the known genes for kidney cancer, VHL, MET, FLCN, TSC1, TSC2, TFE3, TFEB, MITF, fumarate hydratase (FH), succinate dehydrogenase B (SDHB), succinate dehydrogenase D (SDHD), and PTEN genes is involved in the cells ability to sense oxygen, iron, nutrients or energy. Understanding the metabolic basis of kidney cancer will hopefully provide the foundation for the development of effective forms of therapy for this disease.