von Hippel-Lindau disease-associated solid microcystic serous adenomas masquerading as pancreatic neuroendocrine neoplasms

Imaging of pancreatic serous cystadenoma and common imitators

Pancreatic cystic neoplasms are lesions comprised of cystic components that show different biological behaviors, epidemiology, clinical manifestations, imaging features, and malignant potential and management. Benign cystic neoplasms include serous cystic neoplasms (SCAs). Other pancreatic cystic lesions have malignant potential, such as intraductal papillary mucinous neoplasms and mucinous cystic neoplasms. SCAs can be divided into microcystic (classic appearance), honeycomb, oligocystic/macrocystic, and solid patterns based on imaging appearance. They are usually solitary but may be multiple in von Hippel-Lindau disease, which may depict disseminated involvement. The variable appearances of SCAs can mimic other types of pancreatic cystic lesions, and cross-sectional imaging plays an important role in their differential diagnosis. Endoscopic ultrasonography has helped in improving diagnostic accuracy of pancreatic cystic lesions by guiding tissue sampling (biopsy) or cyst fluid analysis. Immunohistochemistry and newer techniques such as radiomics have shown improved performance for preoperatively discriminating SCAs and their mimickers.

Management recommendations for pancreatic manifestations of von Hippel-Lindau disease

Von Hippel-Lindau disease (VHL) is a multineoplasm inherited disease manifesting with hemangioblastoma of the central nervous system and retina, adrenal pheochromocytoma, renal cell carcinoma, pancreatic neuroendocrine tumors and cysts, and neoplasms/cysts of the ear, broad ligament, and testicles. During 2018-2020, the VHL Alliance gathered several committees of experts in the various clinical manifestations of VHL to review the literature, gather the available evidence on VHL, and develop recommendations for patient management. The current report details the results of the discussion of a group of experts in the pancreatic manifestations of VHL along with their proposed recommendations for the clinical surveillance and management of patients with VHL. The recommendations subcommittee performed a comprehensive systematic review of the literature and conducted panel discussions to reach the current recommendations. The level of evidence was defined according to the Shekelle variation of the Grading of Recommendations, Assessment, Development, and Evaluation grading system. The National Comprehensive Cancer Network Categories of Evidence and Consensus defined the committee members' interpretation of the evidence and degree of consensus. The recommendations encompass the main aspects of VHL-related pancreatic manifestations and their clinical management. They are presented in a clinical orientation, including general planning of screening and surveillance for pancreatic neuroendocrine tumors, utility of biochemical biomarkers, the optimal choice for imaging modality, indirect risk stratification, indications for tissue sampling of VHL-related pancreatic neuroendocrine tumors, and interventions. These recommendations are designed to serve as the reference for all aspects of the screening, surveillance, and management of VHL-related pancreatic manifestations.

Molecular Pathology of Well-Differentiated Gastro-entero-pancreatic Neuroendocrine Tumors

Well differentiated neuroendocrine tumors (NETs) arising in the gastrointestinal and pancreaticobiliary system are the most common neuroendocrine neoplasms. Studies of the molecular basis of these lesions have identified genetic mutations that predispose to familial endocrine neoplasia syndromes and occur both as germline events and in sporadic tumors. The mutations often involve epigenetic regulators rather than the oncogenes and tumor suppressors that are affected in other malignancies. Somatic copy number alterations and miRNAs have also been implicated in the development and progression of some of these tumors. The molecular profiles differ by location, but many are shared by tumors in other sites, including those outside the gastroenteropancreatic system. The approach to therapy relies on both the neuroendocrine nature of these tumors and the identification of specific alterations that can serve as targets for precision oncologic approaches.

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.

Serous cystadenoma of pancreas: A clinicopathologic experience of 23 cases from a major tertiary care center

Background:

Serous cystadenomas of pancreas are rare benign epithelial neoplasms, which predominantly occur in the pancreatic body and tail of elderly females. Majority of these tumors have microcystic appearance. Macrocystic and solid variants have also been described. A number of more aggressive cystic pancreatic lesions are included in the differential diagnosis. Distinction from such lesions is important for optimal management.

Objective:

Our aim was to study the clinical and histological features of serous cystadenomas which would be helpful in making their correct diagnosis and understanding their behavior.

Methods:

We reviewed 23 cases of serous cystadenomas diagnosed in our institution between January 2001 and June 2018.

Results:

Mean age at presentation was 53.43 years. Female to male ratio was 4.75:1. Over half (56.5%) of the cases were diagnosed incidentally. Abdominal pain was the most common symptom. Body and tail (either alone or in combination) were the most common locations. Tumor size ranged from 2 to 16 cm. Central scar was seen in 43.4% cases. Two cases were unilocular (macrocystic). Microscopically, all cases showed simple cuboidal to flattened epithelium with round, uniform nuclei, and glycogen-rich clear cytoplasm. Focal micropapillae formation was seen in eight cases (34.7%). Surgical resection was performed in 82.6% cases. Recurrence occurred in only one single case.

Conclusion:

Pancreatic serous cystadenomas are benign neoplasms with excellent prognosis. The tumors showed typical morphological features in all cases. Surgical resection was performed in the majority of cases in our study owing to lack of optimal and complete radiological workup pre-operatively and the concern for not missing and adequately treating pancreatic mucinous cystic neoplasms.

Synchronous Pancreatic Serous Cystic Neoplasm and Duodenal Neuroendocrine Tumor: Case Report and Review of the Literature

Simultaneous presence of pancreatic serous cystic neoplasms and neuroendocrine neoplasms is rare. We present a case with the incidental finding of a duodenal neuroendocrine tumor (NET) with 2 lymph node metastases in a Whipple resection specimen performed to remove a pancreatic cystic neoplasm that postoperatively turned out to represent a serous cystic neoplasm (SCN). The patient was a 75-year-old female. She presented with loss of appetite and weight. Preoperative contrast-enhanced computed tomography scan of the abdomen showed a multicystic lesion in the head of pancreas. On histologic examination of the resection specimen, a pancreatic SCN was found, and in addition in 2 peripancreatic lymph nodes, metastases from a NET. Further examination of the resected specimen revealed a duodenal NET. Review of the literature revealed only one prior study with 4 cases of pancreatic SCN associated with a duodenal NET. In 1 of the 4 cases, the patient had von Hippel-Lindau disease. Our report emphasizes the importance of careful examination of pancreatic resection specimens including the peripancreatic lymph nodes also when dealing with SCNs, as coexisting and more malignant tumors may otherwise be missed.

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 solid serous cystadenoma treated by laparoscopy: Presentation of a new case report and review of the literature

•

Solid-type serous cystadenoma of the pancreas is pauci-symptomatic.

•

Preoperative diagnosis is often misdiagnosis with other solid pancreatic tumors.

•

Laparoscopic resection is feasible for treatment with good prognosis.

Solid serous cystadenoma is an uncommon benign pancreatic tumor, with only, including this case, 21 cases published so far. It is often misdiagnosis with other malignant pancreatic tumors.

Below we report a new case of a solid serous cystadenoma of the pancreas treated by laparoscopic distal pancreatectomy in 53-year-old female who presented with epigastric pain. Histological and immunohistochemical examination revealed a solid serous cystadenoma of the pancreas. Preoperative diagnosis of this subtype of serous cystadenoma is difficult, and, due to its benign nature, conservative resection of the tumor is the recommended treatment.

After analyzing the literature, including this case from our department, we discuss clinical presentation, imaging characteristics and histopathological findings, considering in particular difficulties in preoperative diagnosis, feasibility of laparoscopic resection.

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.

[Von Hippel-Lindau disease type 2-related pancreatic neuroendocrine tumor and adrenal myelolipoma]

The paper describes a case of von Hippel--Lindau-related pancreatic neuroendocrine tumor and adrenal myelolipoma in a 44-year-old woman. The pancreatic tumor and a left retroperitoneal mass were removed in the women in July 2014 and May 2015. Histological examination of the pancreatic tumor revealed that the latter consisted of clear cells forming tubular and tubercular structures showing the expression of chromogranin A, synaptophysin, and cytokeratins 18 and 19 and a negative response to CD10 and RCC. The adrenal medullary mass presented as clear-cell alveolar structures with inclusions of adipose tissue mixed with erythroid, myeloid, and lymphoid cells. The clear-cell component of the adrenal gland expressed neuroendocrine markers with a negative response to cytokeratins, CD10, and RCC. Molecular genetic examination yielded a signal corresponding to two copies of the VHL gene. No deletions or amplifications of the gene were detected. Cases of von Hippel--Lindau disease concurrent with adrenal pheochromocytoma and myelolipoma and simultaneous pancreatic involvement were not found in the literature.

Pancreatic manifestations in von Hippel-Lindau disease: A case report

INTRODUCTION

Pancreatic manifestations in Von Hippel-Lindau (VHL) disease can present as a multitude of forms, and their management can be challenging.

PRESENTATION OF THE CASE

A 66-year-old woman presented with increasing abdominal girth without other associated symptoms of nausea, vomiting, abdominal pain, weight-loss, and jaundice. Her medical and surgical histories were significant for type II diabetes, cerebral tumor resection, bilateral nephrectomies, and laser photocoagulation of retinal hemangiomas. Computed tomography (CT) of the abdomen showed a massive multi-cystic lesion in the pancreas and the patient was referred to our hepatopancreatic biliary center.

DISCUSSION

The findings on the subsequent cross-sectional MRI imaging signified pancreatic manifestations in VHL disease.

CONCLUSION

The management of VHL disease-associated benign pancreatic cystic lesions involves interval monitoring with cross-sectional imaging for malignant changes/development.

Serous Neoplasms of the Pancreas: A Clinicopathologic Analysis of 193 Cases and Literature Review With New Insights on Macrocystic and Solid Variants and Critical Reappraisal of So-called "Serous Cystadenocarcinoma"

The literature on "variants" and "malignant" counterparts of pancreatic serous cystic neoplasms (SCNs) is highly conflicted. Clinicopathologic characteristics of 193 SCNs were investigated, along with a critical literature review. For the macrocystic (oligocystic) variant, in this largest series, a demographic profile in contrast to current literature was elucidated, with 21% frequency, predominance in female individuals (4:1), body/tail location (1.7×), younger age of patients (mean age, 50 y), and frequent radiologic misdiagnosis as other megacystic neoplasms. Solid SCNs were rare (n=4, 2%) and often misinterpreted radiologically as neuroendocrine tumors. Available fine-needle aspiration in 11 cases was diagnostic in only 1. Radiologic impression was "malignancy" in 5%. Associated secondary tumors were detected in 13% of resections, mostly neuroendocrine. Secondary "infiltration" (direct adhesion/penetration) of spleen, stomach, colon, and/or adjacent nodes was seen in 6 (3%) fairly large SCNs (mean, 11 cm) with no distant metastasis. Three SCNs recurred locally, but completeness of original resection could not be verified. Our only hepatic SCN lacked a concurrent pancreatic tumor. Literature appraisal revealed that there are virtually no deaths that are directly attributable to dissemination/malignant behavior of SCNs, and most cases reported as "malignant" in fact would no longer fulfill the more recent World Health Organization criteria but instead would represent either (1) local adhesion/persistence of tumor, (2) cases with no histologic verification of malignancy, or (3) liver SCNs with benevolent behavior (likely representing multifocality, rather than true metastasis, especially considering there was no fatality related to this and no reported metastases to other remote sites). In conclusion, in contrast to the literature, the clinicopathologic characteristics of solid and macrocystic SCN variants are similar to their microcystic counterpart, although their radiologic diagnosis is challenging. Recurrence/secondary invasion of neighboring organs occurs rarely in larger SCNs but seems innocuous. An SCN should not be classified as "malignant" unless there is clear-cut evidence of histologic malignancy or documented distant metastasis.

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.