Neurofibromin and NF1 gene analysis in composite pheochromocytoma and tumors associated with von Recklinghausen's disease

Overview of the 2022 WHO Classification of Familial Endocrine Tumor Syndromes

This review of the familial tumor syndromes involving the endocrine organs is focused on discussing the main updates on the upcoming fifth edition of the WHO Classification of Endocrine and Neuroendocrine Tumors. This review emphasizes updates on histopathological and molecular genetics aspects of the most important syndromes involving the endocrine organs. We describe the newly defined Familial Cancer Syndromes as MAFA-related, MEN4, and MEN5 as well as the newly reported pathological findings in DICER1 syndrome. We also describe the updates done at the new WHO on the syndromic and non-syndromic familial thyroid diseases. We emphasize the problem of diagnostic criteria, mention the new genes that are possibly involved in this group, and at the same time, touching upon the role of some immunohistochemical studies that could support the diagnosis of some of these conditions. As pathologists play an important role in identifying tumors within a familial cancer syndrome, we highlight the most important clues for raising the suspicious of a syndrome. Finally, we highlight the challenges in defining these entities as well as determining their clinical outcome in comparison with sporadic tumors. Instead of the usual subject review, we present the highlights of the updates on familial cancer syndromes by answering select questions relevant to practicing pathologists.

Composite phaeochromocytomas-a systematic review of published literature

Introduction

Composite phaeochromocytoma is a tumour containing a separate tumour of neuronal origin in addition to a chromaffin cell tumour. This study reports on two cases from a single centre’s records and presents a systematic literature review of composite phaeochromocytomas.

Methods

In addition to describing 2 case reports, a systematic search of the Medline database from inception up to April 2020 was done for human case reports on composite phaeochromocytomas. Relevant titles and/or abstracts were screened, and full texts were reviewed to identify appropriate studies. Data was extracted and a descriptive analysis of presentation, clinical features, management strategies and outcomes was performed. The quality of included studies was assessed using a critical appraisal checklist.

Results

There were 62 studies included, with a total of 94 patients. Of 91 patients where data was available, the median (range) age of patients was 48 (4–86) years. Of 90 patients where information was provided, 57% were female. In at least 28% of patients, a genetic cause was identified. Common presenting features include abdominal pain, palpable mass, cardiovascular and gastrointestinal symptoms. The most common tumour component with phaeochromocytoma is ganglioneuroma; other components include ganglioneuroblastoma, neuroblastoma and malignant peripheral nerve sheath tumours. In patients with follow-up data (n=48), 85% of patients were alive and well at a median (range) follow-up time of 18 (0.5–168) months.

Conclusion

Composite phaeochromocytoma is a rare tumour, with a significant genetic predisposition. This review summarises available epidemiological data, which will be useful for clinicians managing this rare condition.

Neurofibromin expression by normal salivary glands

Introduction

Neurofibromin, a protein encoded by the NF1 gene, is mutated in neurofibromatosis 1, one of the most common genetic diseases. Oral manifestations are common and a high prevalence of hyposalivation was recently described in individuals with neurofibromatosis 1. Although neurofibromin is ubiquitously expressed, its expression levels vary depending on the tissue type and developmental stage of the organism. The role of neurofibromin in the development, morphology, and physiology of salivary glands is unknown and a detailed expression of neurofibromin in human normal salivary glands has never been investigated.

Aim

To investigate the expression levels and distribution of neurofibromin in acinar and ductal cells of major and minor salivary glands of adult individuals without NF1.

Material and method

Ten samples of morphologically normal major and minor salivary glands (three samples of each gland: parotid, submandibular and minor salivary; and one sample of sublingual gland) from individuals without neurofibromatosis 1 were selected to assess neurofibromin expression through immunohistochemistry. Immunoquantification was performed by a digital method.

Results

Neurofibromin was expressed in the cytoplasm of both serous and mucous acinar cells, as well as in ducts from all the samples of salivary glands. Staining intensity varied from mild to strong depending on the type of salivary gland and region (acini or ducts). Ducts had higher neurofibromin expression than acinar cells (p = 0.003). There was no statistical association between the expression of neurofibromin and the type of the salivary gland, considering acini (p = 0.09) or ducts (p = 0.50) of the four salivary glands (parotid, submandibular, minor salivary, and sublingual gland). Similar results were obtained comparing the acini (p = 0.35) and ducts (p = 0.50) of minor and major salivary glands. Besides, there was no correlation between the expression of neurofibromin and age (p = 0.08), and sex (p = 0.79) of the individuals, considering simultaneously the neurofibromin levels of acini and duct (n = 34).

Conclusion

Neurofibromin is expressed in the cytoplasm of serous and mucous acinar cells, and ductal cells of salivary glands, suggesting that this protein is important for salivary gland function.

Pheochromocytoma and gastrointestinal stromal tumours in an adult neurofibromatosis type 1 patient: a rare co-occurrence

The risk of tumours including pheochromocytoma and gastrointestinal stromal tumour (GIST) has been reported to be higher in neurofibromatosis type 1 (NF1) patients. The concomitant occurrence of these two tumours was rare in NF1 patient and most were symptomatic. In this case report, we describe the case of a 47-year-old man with NF1 who presented with microscopic haematuria. Neither hypertension nor any gastrointestinal symptoms were reported by the patient. While investigating for haematuria, left adrenal mass and arterial enhancing lesions in the small bowel were incidentally documented during computerised urography. The patient subsequently underwent a left adrenalectomy and small bowel resection. The pheochromocytoma and multiple GIST tumours were diagnosed based on pathology. Here, we discuss the rare association of pheochromocytoma and GIST and the asymptomatic presentation of those tumours in an NF1 patient. We further suggest that in NF1 patients a heightened level of vigilance can help identify this infrequent combination.

A Novel Phenotype of Germline Pathogenic Variants in MAX: Concurrence of Pheochromocytoma and Ganglioneuroma in a Chinese Family and Literature Review

Background:MYC associated factor X (MAX) is a tumor suppressor gene and has been identified as one of the pathogenic genes of hereditary pheochromocytoma (PCC). To date, there have been no reports of ganglioneuroma (GN) with MAX variants. Case Presentation: The proband was a 45-years-old Chinese female with paroxysmal hypertension and palpitations who had undergone adrenalectomy for PCC 14 years ago. Her plasma free normetanephrine and 24-h urinary norepinephrine excretion were significantly increased, and abdominal computed tomography (CT) revealed an irregular mass in the left adrenal region, suggesting a recurrence of PCC. The mass was surgically removed and pathologically diagnosed as PCC with lymph node metastasis. The proband's son suffered from paroxysmal hypertension and palpitations. His plasma free metanephrine levels were normal. CT revealed a mass in the right adrenal. The tumor was surgically removed, and the pathological diagnosis was GN. Genetic testing of peripheral blood DNA revealed that the proband and her son had germline pathogenic MAX variant c.C97T, p.Arg33Ter, while proband's parents did not have MAX variants. Tumor DNA sequencing showed the same MAX variant (c.C97T, p.Arg33Ter) in PCC of the proband and GN of her son, both with retention of heterozygosity. Immunohistochemistry demonstrated loss of MAX protein expression in most tumor cells in PCC of the proband and some Schwannian cells in GN of the proband's son. Conclusion: We report a family with a new clinical phenotype of germline pathogenic variants in MAX who developed both PCC and GN. Germline pathogenic variants in MAX may contribute to the development of GN. Our findings suggest that it is not just paternally inherited MAX variants that can cause tumors.

A Guide to Pheochromocytomas and Paragangliomas

Pheochromocytomas and extra-adrenal paragangliomas are rare neuroendocrine neoplasms with characteristic histologic and immunohistochemical features. These tumors can arise in several anatomic locations, necessitating that their diagnostic recognition extends beyond the realm of endocrine disorders. A practical and reproducible risk stratification system for these tumors is still in development. In this rapidly evolving era of molecular medicine, it is essential for pathologists to equip themselves with a framework for understanding the classification of paragangliomas and pheochromocytomas and be informed of how they might advise their colleagues with regard to prognostication and appropriate follow-up.

Pheochromocytomas and Paragangliomas: New Developments with Regard to Classification, Genetics, and Cell of Origin

Pheochromocytomas (PCC) and paragangliomas (PGL) are rare neuroendocrine tumors that arise in the adrenal medulla and in extra-adrenal locations, such as the head, neck, thorax, abdomen, and pelvis. Classification of these tumors into those with or without metastatic potential on the basis of gross or microscopic features is challenging. Recent insights and scoring systems have attempted to develop solutions for this, as described in the latest World Health Organization (WHO) edition on endocrine tumor pathology. PCC and PGL are amongst the tumors most frequently accompanied by germline mutations. More than 20 genes are responsible for a hereditary background in up to 40% of these tumors; somatic mutations in the same and several additional genes form the basis for another 30%. However, this does not allow for a complete understanding of the pathogenesis or targeted treatment of PCC and PGL, for which surgery is the primary treatment and for which metastasis is associated with poor outcome. This review describes recent insights into the cell of origin of these tumors, the latest developments with regard to the genetic background, and the current status of tumor classification including proposed scoring systems.

An Update on the Histology of Pheochromocytomas: How Does it Relate to Genetics?

Pheochromocytomas are rare neuroendocrine tumors of the adrenal gland, whereas any extra-adrenal tumor with similar histology is designated as paraganglioma. These tumors have a very high rate of germline mutations in a large number of genes, up to 35% to 40%, frequently predisposing for other tumors as well. Therefore, they represent a phenomenal challenge for treating physicians. This review focuses on pheochromocytomas only, with special attention to gross and microscopic clues to the diagnosis of genetic syndromes, including the role of succinate dehydrogenase subunit A and subunit B immunohistochemistry as surrogate markers for genetic analysis in the field of succinate dehydrogenase subunit gene mutations.

Expression of Extracellular Signal-regulated Kinase 5 and Ankyrin Repeat Domain 1 in Composite Pheochromocytoma and Ganglioneuroblastoma Detected Incidentally in the Adult Adrenal Gland

Composite pheochromocytoma (cPC) is extremely rare, arising in the adrenal medulla as a mixture of PC and other tumors of neural origin. We herein report on a case of adrenal incidentaloma post-operatively diagnosed as cPC with ganglioneuroblastoma (GNBL). The PC component had 7 points on the PASS, a Ki-67 index of 5.1%, a focal absence of sustentacular cells, and no genetic aberrations in succinate dehydrogenase subunit B. The GNBL component exhibited no N-myc amplification. Tumor cells of both components were stained positively for extracellular signal-regulated kinase 5 and ankyrin repeat domain 1. The aberrant activation of growth signaling may play a role in the marginal malignancy of cPC.

A pathologist's view: molecular profiles for diagnosing pheochromocytomas and paragangliomas

Pheochromocytomas (PCC) and paragangliomas (PGL) are catecholamine (CA)-producing tumors classified into well (WD)-, moderately (MD)- or poorly differentiated (PD) types by the Grading of Adrenal Pheochromocytoma and Paraganglioma (GAPP). Seventy percent of PCCs/PGLs are WD type with 4% metastasis, the rest are MD with 60% and PD are with 88% metastasis. Thus, PCCs/PGLs can also be classified as low-grade (WD type), intermediate grade (MD type) and high-grade malignancies (PD types). MD/PD types are with 70% metastasis. Thus, PCCs/PGLs can also be classified as low-grade (WD type) and high-grade malignancies (MD/PD types) using GAPP. Hereditary PCCs/PGLs have been previously classified into cluster 1 or cluster 2 based on genetic mutations involved and types of catecholamine produced by the tumors. GAPP revealed that tumors in cluster 1 and cluster 2 correspond to MD type and WD type, respectively. Susceptible genes for high-grade malignancy (PD type) are currently unknown.

Composite pheochromocytoma masquerading as solid-pseudopapillary neoplasm of pancreas

Pheochromocytoma and ganglioneuroma form rare composite tumours of the adrenal medulla comprising less than 3% of all sympathoadrenal tumours. We present a case of intraoperatively detected adrenal medullary tumour of composite pheochromocytoma and ganglioneuroma diagnosed on histopathology, in a normotensive patient. A 50-year-old male with a past history of chronic obstructive pulmonary disease presented with abdominal pain and significant weight loss since one month. Ultrasound and contrast-enhanced computed tomography abdomen revealed a large lobulated lesion in the distal body and tail of pancreas suggestive of solid and papillary neoplasm of body and tail of pancreas. Intra-operatively, a 15 cm × 10 cm solid lesion with cystic areas was seen arising from the left lower pole of the adrenal gland pushing the pancreas which appeared unremarkable. In our case, exploratory laparotomy with tumour excision was done. Extensive sectioning and microscopic examination of this adrenal tumour confirmed a diagnosis of composite Pheochromocytoma with Ganglioneuroma on histopathology. Immunophenotyping with S-100 further supported the diagnosis. The goal of this report is to increase the awareness of this rare disease and to further identify its variable presentation.

High prevalence of hyposalivation in individuals with neurofibromatosis 1: a case-control study

Background

Neurofibromatosis type 1 (NF1) is one of the most common genetic diseases in humans and has widely variable expressivity. Oral manifestations are common, but there are no studies that investigated functional alterations in salivary glands in NF1. Our aim was to evaluate the salivary flow rate in NF1 individuals, comparing to a control group, and to investigate the possible causes and some consequences of salivary gland alteration.

Methods

This is a case–control study that evaluated the salivary flow rate of NF1 individuals (n = 49) and compared to an age and sex-matched control group. We have also investigated the possible causes and consequences of hyposalivation in NF1 individuals through anamnesis, a specific questionnaire, physical examination, tongue coating evaluation and cytopathological exam to assess the prevalence of oral candidiasis.

Results

Hyposalivation at rest was present in 59% (29/49) of NF1 individuals in contrast to 22% (11/49) in the control group, being statistically significant (P <0.0001; Wilcoxon rank-sum test). The analysis of the adjusted residual showed that the prevalence of hyposalivation in NF1 individuals (46.9%) was 4-fold higher than in controls (10.2%). None of the possible causes of hyposalivation (medications, low liquid intake, caffeinated or stimulant drink use, mouth breathers, alcohol, smoke and plexiform neurofibroma close to or involving major salivary glands areas) had important impact on the salivary flow rate in NF1 individuals.

Conclusions

Hyposalivation may be a consequence of NF1, as occurs in other genetic diseases. More studies are necessary to understand if there is and what is the relationship between NF1 and hyposalivation.

Electronic supplementary material

The online version of this article (doi:10.1186/s13023-015-0239-4) contains supplementary material, which is available to authorized users.

A mimic of sarcomatoid adrenal cortical carcinoma: epithelioid angiosarcoma occurring in adrenal cortical adenoma

The adrenal gland is a site of various neoplasms; however, it is rarely involved by sarcomas. We present herein an unusual adrenal neoplasm consisting of epithelioid angiosarcoma and adrenal cortical adenoma. In this report, the authors highlight the diagnostic challenges associated with an epithelioid angiosarcoma occurring in an adrenal cortical neoplasm by providing a comprehensive discussion on the spectrum of vascular proliferations seen in the adrenal gland along with a roadmap for practicing pathologists. The presence of angiosarcoma within an adrenal cortical adenoma may represent a collision tumor; however, one can speculate that the rich vasculature of endocrine lesions can also create a favorable milieu for the occurrence of this phenomenon. While the latter needs to be further clarified, the presented case should be added to the unusual clinical presentations of vascular lesions of the adrenal gland mimicking a sarcomatoid adrenal cortical carcinoma.

Clinical and radiologic features of pheochromocytoma/ganglioneuroma composite tumors: a case series with comparative analysis

OBJECTIVE

To describe and compare the clinical, biochemical, radiologic, and pathologic features of adrenal pheochromocytoma-ganglioneuroma (PC-GN) composites with the features of isolated pheochromocytomas (PCs) and adrenal ganglioneuromas (AGNs).

METHODS

We reviewed data for PC-GN composite cases seen at a single tertiary center between 1993 and 2012 and compared them with cases of isolated AGN and relatively similar median-size PCs.

RESULTS

Nine PC-GN composites were included. The median age at diagnosis was 52 years (range, 28 to 83 years) for PC-GN compared with 55 years (range, 24 to 78 years) for PC patients and 40 years (range, 18 to 64 years) for AGN patients. Similar to PCs, all PC-GN composites were associated with catecholamine overproduction, whereas AGNs were nonfunctioning. On pathology, the median tumor sizes were 7 cm (range, 2.5 to 13 cm) for PC-GN tumors, 6.5 cm (range, 3.5 to 7 cm) for PCs, and 8 cm (range, 3.2 to 20 cm) for AGNs. On computed tomography (CT) imaging, PC-GN composites and PCs were heterogeneous, with both having significantly higher postcontrast density values than AGNs, which typically looked homogeneous and had a progressive enhancement pattern without contrast washout in most cases.

CONCLUSION

The presence of a PC component significantly increases tumor heterogeneity and postcontrast density values. CT imaging could be very helpful in distinguishing AGNs from both PC-GN and PC tumors, but only pathologic examination can yield the diagnosis. Clinically and radiologically, PC-GN composites are indistinguishable from PCs and need to be managed similarly.

Paragangliomas: update on differential diagnostic considerations, composite tumors, and recent genetic developments

Recent developments in molecular genetics have expanded the spectrum of disorders associated with pheochromocytomas (PCCs) and extra-adrenal paragangliomas (PGLs) and have increased the roles of pathologists in helping to guide patient care. At least 30% of these tumors are now known to be hereditary, and germline mutations of at least 10 genes are known to cause the tumors to develop. Genotype-phenotype correlations have been identified, including differences in tumor distribution, catecholamine production, and risk of metastasis, and types of tumors not previously associated with PCC/PGL are now considered in the spectrum of hereditary disease. Important new findings are that mutations of succinate dehydrogenase genes SDHA, SDHB, SDHC, SDHD, and SDHAF2 (collectively "SDHx") are responsible for a large percentage of hereditary PCC/PGL and that SDHB mutations are strongly correlated with extra-adrenal tumor location, metastasis, and poor prognosis. Further, gastrointestinal stromal tumors and renal tumors are now associated with SDHx mutations. A PCC or PGL caused by any of the hereditary susceptibility genes can present as a solitary, apparently sporadic, tumor, and substantial numbers of patients presenting with apparently sporadic tumors harbor occult germline mutations of susceptibility genes. Current roles of pathologists are differential diagnosis of primary tumors and metastases, identification of clues to occult hereditary disease, and triaging of patients for optimal genetic testing by immunohistochemical staining of tumor tissue for the loss of SDHB and SDHA protein. Diagnostic pitfalls are posed by morphological variants of PCC/PGL, unusual anatomic sites of occurrence, and coexisting neuroendocrine tumors of other types in some hereditary syndromes. These pitfalls can be avoided by judicious use of appropriate immunohistochemical stains. Aside from loss of staining for SDHB, criteria for predicting risk of metastasis are still controversial, and "malignancy" is diagnosed only after metastases have occurred. All PCCs/PGLs are considered to pose some risk of metastasis, and long-term follow-up is advised.

Retroperitoneal composite pheochromocytoma-ganglioneuroma : a case report and review of literature

Abstract

Composite pheochromocytoma/paraganglioma is a rare tumor with elements of pheochromocytoma/paraganglioma and neurogenic tumor. Most were located in the adrenal glands, and extra-adrenal composite pheochromocytoma is extremely rare. Only 4 cases in the retroperitoneum have been described in the online database PUBMED. Here, we report a case of retroperitoneal extra-adrenal composite pheochromocytoma and review the related literature.

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1700539911908679

The role of angiogenesis in the transformation of plexiform neurofibroma into malignant peripheral nerve sheath tumors in children with neurofibromatosis type 1

PURPOSE

The role of angiogenesis in the transformation of peripheral neurofibroma (PNF) to malignant peripheral nerve sheath tumor (MPNST) in neurofibromatosis type 1 (NF1) remains elusive and forms the objective of this study.

EXPERIMENTAL DESIGN

Archival tissue from 5 children with NF1 and PNF, who developed MPNST between the ages of 8 and 15 years were analyzed for differences in microvasculature. The role of proangiogenic growth factors such as Vascular Endothelial Growth Factor (VEGF), and its receptors Flk-1 and Flt-1, and vessel maturity, defined as von Willebrand factor (vWf), α-smooth muscle actin+ (SMA+), were evaluated by immuno-histochemistry.

RESULTS

A qualitative evaluation of the vasculature showed predominantly α-SMA+/vWf+ more stable vessels in PNF, and an irregular meshwork of α-SMA-/vWf+ endothelial cells structures in MPNST. In NF and PNF tumor cells were VEGF-, in contrast to VEGF+ tumor cells in MPNST. If present, the VEGF stain was confined mainly to the perivascular spaces in PNF, unlike the mainly stromal VEGF stain in MPNST. VEGF receptors also manifested a tumor stage-specific pattern. Flk-1 and Flt-1 were restricted to the mature, well-formed vasculature in PNF, but exhibited a diffuse pattern in MPNST.

CONCLUSION

Our study provides a rare opportunity to document consistent and histologically detectable differences in the vascular organization of PNF and MPNST. It permits a pair-wise evaluation of the malignant conversion of benign PNF into its malignant counterpart, in the same patients. The phenotypic variations and characteristics of the vessels in these tumors are consistent with the idea that a strong proangiogenic drive contributes to the progressive growth in MPNST.

Composite pheochromocytoma-ganglioneuroma: a rare experiment of nature

OBJECTIVE

To present a rare case of composite pheochromocytoma-ganglioneuroma (Pheo-GN) of the adrenal medulla, review the related literature, and discuss the clinical features, pathologic findings, behavior, and management of such tumors.

METHODS

A case report of a patient with composite Pheo-GN of the adrenal gland is presented. Using the online database PUBMED, we searched and analyzed all cases of composite pheochromocytoma reported in the English-language literature during the past 70 years.

RESULTS

On computed tomography, a 61-year-old man was incidentally found to have a 3.8-cm nonadenomatous right adrenal lesion. Adrenalectomy revealed a 5-cm mass consistent with composite Pheo-GN. To date, 45 cases of composite pheochromocytomas have been reported during the past 70 years, 71% of which coexisted with ganglioneuromas. These tumors occurred with approximately equal frequency in male and female patients, the majority of whom were from 40 to 60 years old. Only 14 cases have been reported in the United States. Bilateral tumors were found in 3 cases. The mean size was 4 to 6 cm. Preoperatively, functional evidence was found in 76.3% of all composite pheochromocytomas (and in 67% of Pheo-GN). Only one Pheo-GN was found to have liver metastatic lesions at the time of autopsy; the rest were not aggressive.

CONCLUSION

To our knowledge, this is the first literature review describing the characteristics and behavior of all reported cases of composite pheochromocytomas, with an emphasis on those with ganglioneuromas. Composite pheochromocytoma is a rare variant of a relatively uncommon disease diagnosed by pathologists only. Fortunately, the treatment of such an entity remains the same as for any pheochromocytoma.

Uncommon clinical presentations of pheochromocytoma and paraganglioma in two different patients affected by two distinct novel VHL germline mutations

CONTEXT

The von Hippel-Lindau (VHL) syndrome is an inherited multitumour disorder characterized by clinical heterogeneity and high penetrance. Pheochromocytoma (Pheo) is present in 10%-15% of cases and can be isolated or associated with other lesions such as haemangioblastomas, kidney cysts or cancer and pancreatic lesions. In VHL patients, Pheos generally secrete norepinephrine and are located in the adrenals. Extra-adrenal Pheos (paragangliomas, PGLs) are rare.

OBJECTIVE

While performing genetic testing in patients affected by apparently sporadic Pheos or PGLs, we found two novel different VHL germline mutations in two females who presented with two distinct very uncommon clinical pictures. One patient was studied for the presence of an adrenal incidentaloma and the other for the presence of a neck tumour.

METHODS AND RESULTS

Patients coding regions and exon-intron boundaries of RET (exons 10, 11, 13-15), VHL, SDHD, SDHB and SDHC genes were amplified and sequenced. We identified two novel VHL point mutations: a L198V missense mutation in a 32-year-old female affected by a right adrenal compound and mixed tumour constituted by an epinephrine secreting Pheo, a ganglioneuroma and an adrenocortical adenoma, and a T152I missense mutation in a 24-year-old female affected by a left carotid body tumour. No other lesions were found in the patients or in the VHL mutation positive relatives.

CONCLUSIONS

These cases enlarge the list of VHL mutations and add new insights in the clinical variability of VHL disease, thus confirming the importance of genetic testing in patients affected by apparently sporadic Pheos or PGLs.

Multiple gastrointestinal stromal tumors and bilateral pheochromocytoma in neurofibromatosis

The coincidence of a gastrointestinal stromal tumor (GIST) and a neuroendocrine tumor (NET) in neurofibromatosis type 1 (NF1) is described only five times within the literature. We report on a 63 year old Caucasian female with the rare condition of neurofibromatosis type 1 coinciding with recurrent gastrointestinal stromal tumor plus bilateral pheochromocytoma (PCC). After a history of palpitations and dizziness that lasted for years, a left adrenal mass was detected by CT. Laparotomy revealed a pheochromocytoma of the left adrenal gland while an ileoterminal GIST was found incidentally intraoperatively. After six months contralateral PCC and multiple recurrent GIST were resected again. After four years the patient is doing well without any signs of further recurrent tumors. Discussion includes review of the literature.

Unusual association of adrenal pheochromocytoma and para-aortic neurofibroma in pregnancy

The association of pheochromocytoma (PHEO) and pregnancy is uncommon and life threatening for both the fetus and the mother. Early diagnosis and treatment is essential to decrease maternal and fetal mortality and to differentiate the disease from the more common pre-eclampsia. While medical treatment should be started immediately after diagnosis, the timing of surgical treatment is still debated. We describe the case of a 27-yr-old woman in the 18th week of pregnancy who showed a biochemical pattern typical of PHEO and, by imaging studies, 2 tumors with the same characteristics: the first localized on the right adrenal gland, the second at the right renal hilum. The patient underwent surgery because of suspicion of malignant PHEO with local metastasis, while histology revealed a rare association of a solitary PHEO and para-aortic neurofibroma, both tumors embryologically deriving from a common cell precursor.

Familial pheochromocytomas and paragangliomas: stories from the sign-out room

In this overview we present five patients with apparently sporadic pheochromocytomas or paragangliomas which turned out to be associated with an inheritable familial disease. For each patient a family history together with clinical, morphological, as well as molecular data are reported. The identified syndromes include multiple endocrine neoplasia type 2 (MEN2), von Hippel-Lindau syndrome (VHL), neurofibromatosis type 1 (NF1), and familial pheochromocytoma/paraganglioma syndrome (SDHx). A brief summary of phenotypes, the genes involved, and typical mutations in these syndromes is provided.

Unique association of non-functioning pheochromocytoma, ganglioneuroma, adrenal cortical adenoma, hepatic and vertebral hemangiomas in a patient with a new intronic variant in the VHL gene

We analyzed the clinical, hormonal, immunohistochemical and genetic features in a 69-yr-old Caucasian woman with a very rare "composite and mixed pheochromocytoma". This was characterized by right adrenal pheochromocytoma associated with homolateral ganglioneuroma and controlateral adrenal cortical adenoma. The three tumors, incidentally discovered, proved to be non-functioning (normal secretion of catecholamines and of other neuroendocrine peptides, glucocorticoids, mineralcorticoids and androgens). Accordingly, the patient showed no sign or symptom of endocrine disease. Computed tomography (CT) and magnetic resonance (MR) demonstrated a typical adenomatous lesion on the left adrenal gland with precocious uptake of the radiotracer on radioidine (131I)-norcholesterol adrenal scintigraphy, while the controlateral gland showed hyperdensity on CT, hyperintensity on MR and no uptake at adrenal scintigraphy. In addition, CT and MR revealed a vertebral and two hepatic hemangiomas. The right adrenal gland was surgically removed and, microscopically, pheochromocytoma and ganglioneuroma areas appeared intermixed without a predominant component. The former showed strong immunoreactivity for chromogranin, synaptophysin, vascular endothelial growth factor (VEGF) and CD34, while the latter appeared positive for neuron-specific enolase (NSE) and S-100. Peripheral blood genomic DNA analysis revealed a new intronic variant (5557A > G) in the von Hippel-Lindau gene (VHL) not observed in our control population.

Hereditary hormone excess: genes, molecular pathways, and syndromes

Hereditary origin of a tumor helps toward early discovery of its mutated gene; for example, it supports the compilation of a DNA panel from index cases to identify that gene by finding mutations in it. The gene for a hereditary tumor may contribute also to common tumors. For some syndromes, such as hereditary paraganglioma, several genes can cause a similar syndrome. For other syndromes, such as multiple endocrine neoplasia 2, one gene supports variants of a syndrome. Onset usually begins earlier and in more locations with hereditary than sporadic tumors. Mono- or oligoclonal ("clonal") tumor usually implies a postnatal delay, albeit less delay than for sporadic tumor, to onset and potential for cancer. Hormone excess from a polyclonal tissue shows onset at birth and no benefit from subtotal ablation of the secreting organ. Genes can cause neoplasms through stepwise loss of function, gain of function, or combinations of these. Polyclonal hormonal excess reflects abnormal gene dosage or effect, such as activation or haploinsufficiency. Polyclonal hyperplasia can cause the main endpoint of clinical expression in some syndromes or can be a precursor to clonal progression in others. Gene discovery is usually the first step toward clarifying the molecule and pathway mutated in a syndrome. Most mutated pathways in hormone excess states are only partly understood. The bases for tissue specificity of hormone excess syndromes are usually uncertain. In a few syndromes, tissue selectivity arises from mutation in the open reading frame of a regulatory gene (CASR, TSHR) with selective expression driven by its promoter. Polyclonal excess of a hormone is usually from a defect in the sensor system for an extracellular ligand (e.g., calcium, glucose, TSH). The final connections of any of these polyclonal or clonal pathways to hormone secretion have not been identified. In many cases, monoclonal proliferation causes hormone excess, probably as a secondary consequence of accumulation of cells with coincidental hormone-secretory ability.

Hypokalemic rhabdomyolysis due to WDHA syndrome caused by VIP-producing composite pheochromocytoma: a case in neurofibromatosis type 1

A 47-year-old woman with neurofibromatosis type 1 suffered from general muscle weakness and watery diarrhea. Laboratory findings showed elevated muscular enzymes, severe hypokalemia and excessive production of catecholamines and vasoactive intestinal polypeptide (VIP). A computed tomography scan showed a 10 cm left adrenal mass, in which [(131)I]-metaiodobenzylguanidine scintigraphy showed high uptake. After she underwent surgical removal of the tumor, all the symptoms and signs subsided. A histological study revealed that the mass consisted of pheochromocytoma and ganglioneuroma, respectively producing catecholamines and VIP. In immunohistochemical staining of neurofibromin, pheochromocytoma and ganglion cells showed positive staining, whereas the staining was negative for nerve bundles and Schwann cells. We concluded that the patient had hypokalemic rhabdomyolysis due to watery diarrhea, hypokalemia and achlorhydria (WDHA) syndrome, which was induced by a VIP-producing composite pheochromocytoma. Composite pheochromocytoma is a neuroendocrine tumor that is composed of pheochromocytoma and ganglioneuroma, both derived from the neural crest. Deficiency of neurofibromin in Schwann cells might have played an important role in the development and the growth of the composite pheochromocytoma in this patient.