Von Hippel-Lindau disease

A Case of von Hippel-Lindau Disease with Colorectal Adenocarcinoma, Renal Cell Carcinoma and Hemangioblastomas

von Hippel–Lindau (VHL) disease is an autosomal dominant inherited tumor syndrome associated with mutations of the VHL tumor suppressor gene located on chromosome 3p25. The loss of functional VHL protein contributes to tumorigenesis. This condition is characterized by development of benign and malignant tumors in the central nervous system (CNS) and the internal organs, including kidney, adrenal gland, and pancreas. We herein describe the case of a 74-year-old man carrying the VHL gene mutation who was affected by simultaneous colorectal adenocarcinoma, renal clear cell carcinoma, and hemangioblastomas of CNS.

von Hippel Lindau disease with colon adenocarcinoma, renal cell carcinoma and adrenal pheochromocytoma

von Hippel-Lindau (VHL) disease is an autosomal dominant inherited tumor syndrome characterized by the presence of heterogeneous tumors derived from different organs. VHL is caused by germline mutations in the VHL tumor suppressor gene located on chromosome 3p25-26. The loss of functional VHL protein contributes to tumorigenesis. VHL tumors are most frequently derived from the kidneys, adrenal gland, central nervous system, eyes, inner ear, epididymis and pancreas. We herein describe the case of a 64-year-old man carrying the VHL gene mutation affected by simultaneous colon adenocarcinoma, renal clear cell carcinoma and adrenal pheochromocytoma.

Pancreatic manifestations of von Hippel-Lindau disease

Von Hippel-Lindau disease is an uncommon, multisystem, multitumor disorder that can present in sporadic form but is more commonly inherited as an autosomal-dominant disease with high penetrance. Affected patients are at increased risk for developing multiple synchronous or metachronous benign or malignant, cystic, and vascular neoplasms of various organs. The characteristic neoplasms associated with von Hippel-Lindau are hemangioblastoma of the central nervous system and retina, clear cell renal cell carcinoma, and pheochromocytoma, but other lesions are well recognized. Pancreatic lesions, both primary and metastatic, are common, and several differential diagnostic possibilities must be considered.

VHL deletion impairs mammary alveologenesis but is not sufficient for mammary tumorigenesis

Overexpression of hypoxia inducible factor-1 (HIF-1)alpha, which is common in most solid tumors, correlates with poor prognosis and high metastatic risk in breast cancer patients. Because HIF-1alpha protein stability is tightly controlled by the tumor suppressor von Hippel-Lindau (VHL), deletion of VHL results in constitutive HIF-1alpha expression. To determine whether VHL plays a role in normal mammary gland development, and if HIF-1alpha overexpression is sufficient to initiate breast cancer, Vhl was conditionally deleted in the mammary epithelium using the Cre/loxP system. During first pregnancy, loss of Vhl resulted in decreased mammary epithelial cell proliferation and impaired alveolar differentiation; despite these phenotypes, lactation was sufficient to support pup growth. In contrast, in multiparous dams, Vhl(-/-) mammary glands exhibited a progressive loss of alveolar epithelium, culminating in lactation failure. Deletion of Vhl in the epithelium also impacted the mammary stroma, as there was increased microvessel density accompanied by hemorrhage and increased immune cell infiltration. However, deletion of Vhl was not sufficient to induce mammary tumorigenesis in dams bred continuously for up to 24 months of age. Moreover, co-deletion of Hif1a could not rescue the Vhl(-/-)-dependent phenotype as dams were unable to successfully lactate during the first lactation. These results suggest that additional VHL-regulated genes besides HIF1A function to maintain the proliferative and regenerative potential of the breast epithelium.

Normalization of systemic arterial hypertension following removal of posterior fossa hemangioblastoma: a case report

The concept of compression of the rostral ventrolateral medulla as a cause for hypertension is gaining more and more interest. This report is about a 36-year-old male with a three years history of hypertension who presented with a posterior fossa mass suggestive of a hemangioblastoma. Laboratory and imaging studies ruled out the presence of von Hippel-Lindau disease and/or concomitant pheochromocytoma. Post-surgical blood pressure monitoring revealed a 40 mmHg decline in blood pressure. It could be hypothesized that alleviation the compressive effect of the tumour on the rostral ventrolateral medulla as proposed by previous studies could be a contributing factor.

Hypoxia-Inducible Factor in Ringed Seal (Phoca hispida) Tissues

Tissue hypoxia and ischemia-reperfusion pose a dangerous situation for oxidative stress. However, diving mammals and birds show pronounced resistance to oxidative injury under such conditions, which are a consequence of selective vasoconstriction during a dive. As the function of Hypoxia-Inducible Factor-1alpha (HIF-1alpha) in protection against and adaptation to hypoxia has been recognized in terrestrial animals, we have investigated the genomics and expression of this protein in ringed seal (Phoca hispida) in order to determine if it may play a protective role in this diving mammal. PCR studies using primers based on sequences from mouse HIF-1alpha exons 3, 4, 5, 6, 9, 10, 11, 12 and 15 showed that DNA from seal lung generated PCR products similar to those from mouse DNA. These studies have established that a putative HIF-1alpha gene exists in the seal genome that appears to have a similar but not identical sequence to the mouse gene. Seal lung and skeletal muscle tissues showed the highest relative levels of HIF-1alpha protein expression, with heart muscle showing significantly lower levels, and levels of HIF-1beta protein expression paralleled this situation. Analysis of oxidized cellular protein levels indicated that seal lung and heart muscle had the lowest levels of oxidized proteins. Thus, as seal lung tissue had the highest level of HIF-1alpha protein expression and the second lowest level of protein oxidation, this suggests that HIF-1alpha expression may have an important protective effect in this tissue in diving mammals. Our results support the hypothesis that HIF-1alpha expression is dependent on both tissue-specific energy requirements and adequate metabolic supply-to-demand ratio. Combined, the evidence available suggests that diving mammals have an overall anticipatory response to avoid the ill effects of dive-associated ischemia-reperfusion which may involve the HIF-1 system.

Lifestyle Factors, Exposures, Genetic Susceptibility, and Renal Cell Cancer Risk: A Review

Malignant kidney tumors account for approximately 2% of all new primary cancer cases diagnosed in the United States, with an estimated 30,000 cases occurring annually. Although a variety of agents, chemical and biological, have been implicated as causal agents in the development of renal cell carcinoma (RCC), the etiology remains enigmatic. The strongest association has been developed between cigarette smoking and renal cancer however consistent, positive associations between RCC and obesity, diabetes, and hypertension have also been reported. In addition, more recent investigations of familial kidney cancer syndromes indicate that a strong genetic component contributes to RCC development. Several genes have been identified through investigation of familial kidney cancer syndromes. This review article describes recent trends in RCC incidence and the currently identifiable etiological causes that account for approximately half of the RCC cases diagnoses. The remainder of this review then focuses on additional risk factors that have thus far not been well examined but may be helpful in explaining the increasing incidence trends and the geographic or racial variation observed nationally and worldwide.

Endoscopic ultrasound-guided fine-needle aspiration diagnosis of clear-cell pancreatic endocrine neoplasm in a patient with von Hippel-Lindau disease: a case report

The cytologic findings of a clear-cell pancreatic endocrine neoplasm (PEN) diagnosed by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) occurring in a 29-year-old man with von Hippel-Lindau (VHL) syndrome are described. Imaging studies showed multiple pancreatic masses and cysts, a single liver lesion, and pulmonary and renal cysts. Cytologic features of this clear-cell PEN included the presence of large sheets and rounded clusters of polygonal neoplastic cells with relatively abundant cytoplasm containing numerous, small, sharply-demarcated vacuoles that occasionally indented nuclei and gave the cells a "frothy" appearance. Mild anisonucleosis was present and nucleoli were visible. Rare single cells and stripped nuclei were seen. Small vessels transgressed tumor cell sheets. These cytologic findings are distinct from those of typical endocrine neoplasms, and bear resemblance to the cytologic features of renal cell carcinoma metastatic to the pancreas. To the best of our knowledge, this is the first detailed report of the EUS-FNA cytologic findings of a clear-cell PEN associated with VHL syndrome. We believe that the distinctive and characteristic cytologic features, together with immunohistochemical studies, can allow a preoperative cytologic diagnosis of this highly unusual pancreatic lesion and avoid possible confusion with other clear-cell neoplasms in the pancreas, particularly metastatic renal cell carcinoma.

Normalization of systemic arterial hypertension following removal of posterior fossa hemangioblastoma: a case report

The concept of compression of the rostral ventrolateral medulla as a cause for hypertension is gaining more and more interest. This report is about a 36-year-old male with a three years history of hypertension who presented with a posterior fossa mass suggestive of a hemangioblastoma. Laboratory and imaging studies ruled out the presence of von Hippel-Lindau disease and/or concomitant pheochromocytoma. Post-surgical blood pressure monitoring revealed a 40 mmHg decline in blood pressure. It could be hypothesized that alleviation the compressive effect of the tumour on the rostral ventrolateral medulla as proposed by previous studies could be a contributing factor.

Carcinoid tumor of the common bile duct: A rare complication of von Hippel-Lindau syndrome

Von Hippel-Lindau syndrome (VHL) is a rare autosomal-dominant, inherited familial cancer syndrome. Hemangioblastomas, pheochromocytomas and renal carcinoma are the frequent reported VHL tumors. Neuroendocrine tumors have also been described, mostly in the pancreas and rarely in the biliary trees. We report the second case of bile duct carcinoid in a 31-year-old VHL woman. She underwent right adrenalectomy for a pheochromocytoma in the past. She also had a positive family history of phenotypic expression of VHL syndrome. The patient presented with biliary colic. Endoscopic retrograde cholangio-pancreatography showed intra-luminal bile duct mass. Surgical exploration identified a beige nodular lesion that was a carcinoid tumor on histology. This new association should be clarified by further genetic investigations.

Sonography of benign renal cystic disease

When evaluating renal cystic mass lesions, ultrasound plays an important part in distinguishing cysts from solid lesions and in demonstrating the complex internal architecture of cystic lesions. Ultrasound is usually the initial imaging modality for patients who have medical renal disease. When renal cystic disease is identified, it is extremely important to accurately communicate the findings and attempt to distinguish benign from surgical lesions.

Disseminated haemangioblastoma without evidence of the von Hippel-Lindau syndrome or haemangioblastomatosis--A case report and clinico-pathological correlation

A 71-year-old Caucasian female presented to our service with disseminated cranial and spinal haemangioblastomata but no other features to suggest the von Hippel-Lindau syndrome. We feel that this represents cellular dissemination through the cerebro-spinal fluid and may be an intermediate step to the development of frank haemangioblastomatosis. By comparing this presentation to that of other tumours we have suggested a potential pathological mechanism and have discussed its management.

VHL P25L is not a pathogenic von Hippel-Lindau mutation: a family study

BACKGROUND

von Hippel-Lindau (VHL) disease is a hereditary tumor syndrome in which affected individuals may develop CNS and retinal hemangioblastomas, pheochromocytomas, renal cell carcinoma, and cysts of various organs. The VHL gene has been localized to chromosome 3p25-26 and >500 germline mutations have been identified. A rare variant of the VHL gene results in the substitution of lysine for proline at position 25 (P25L) in the larger of the two VHL proteins. This VHL variant has previously been described in a limited number of cases and has been strongly suggested to be non-pathogenic, but this has not been proven.

METHODS

A family with a medical history suggestive of VHL disease was investigated using DNA sequence analysis to determine the presence of the P25L variant of the VHL protein.

RESULTS

Sequence analysis identified the VHL P25L variant in 7 of 14 family members, one of whom had a single retinal hemangioma, which is in itself insufficient to diagnose VHL disease. The variant was not identified in a family member with clear cell renal carcinoma, which is a hallmark feature of VHL disease.

CONCLUSIONS

On the basis of these results, it is concluded that P25L is a benign variant of the VHL protein and individuals carrying this variant should not be required to undergo screening for VHL manifestations.

Lipid-Rich Variant of Pancreatic Endocrine Neoplasms

Most pancreatic endocrine neoplasms (PENs) show characteristic and well-recognized endocrine morphology; however, a lipid-rich pattern, which can present a diagnostic problem in biopsies, has been reported, mostly as individual cases. Some have been included in descriptions of the rare clear-cell variant associated with von Hippel-Lindau (VHL) syndrome. The histogenesis, clinicopathologic characteristics, and significance of this lipid-rich pattern have not been unraveled. In this study, 11 PENs exhibiting foamy, microvesicular cytoplasm were analyzed. In some cases, the nuclei were distorted by the vesicles, and the usual endocrine chromatin pattern was not evident. The growth pattern was relatively diffuse, with vague compartmentalization of the cells by a delicate vasculature; prominent nesting was noted in only 4 cases. Pathology reports indicated substantial diagnostic challenge in these cases; on biopsies, 1 case was originally diagnosed as adrenal cortical carcinoma, another as renal cell carcinoma, a third as solid-pseudopapillary tumor, and a fourth had a fine needle aspiration cytologic diagnosis of adenocarcinoma. All cases were chromogranin and synaptophysin positive. Electron microscopy in 3 cases confirmed the cytoplasmic vesicles to be lipid vacuoles. Neurosecretory granules were also evident. Clinically, as in conventional PENs, there appeared to be two distinct subsets: Two cases were familial or functional/syndromic (1 with VHL and the other with MEN-1 and glucagonoma syndrome) and occurred in younger adults (ages 41 and 47 years); the majority (n = 9) were nonfunctional/nonsyndromic and nonfamilial. The latter group was mostly represented by elderly males (mean age: 65 vs. 58 years in conventional sporadic PENs). Immunohistochemically, markers implicated in VHL-associated neoplasia, including HIF-1alpha, inhibin, and Melan-A (in clear-cell PENs) and MUC6 (in serous cystadenomas) were mostly negative in lipid-rich PENs (1 of 10, 1 of 10, 0 of 10 and 0 of 10, respectively). In conclusion, the lipid-rich pattern, reminiscent of adrenal cortical cells, represents a distinct subset of PENs. It presents a diagnostic challenge for surgical pathologists, especially in biopsies. EM supports the name lipid-rich for this variant. The findings suggest that the pathogenesis of lipid-rich tumors may be different from the VHL-associated clear-cell variants of PENs.

Investigating the potential of bevacizumab in other indications: metastatic renal cell, non-small cell lung, pancreatic and breast cancer

Bevacizumab (Avastin) has unprecedented survival benefit in patients with metastatic colorectal cancer. Trials are already in progress to investigate the potential of bevacizumab in indications including metastatic renal cell cancer (RCC), non-small cell lung cancer (NSCLC), pancreatic cancer, breast and ovarian cancer. Bevacizumab offers the potential to increase survival without substantially altering the toxicity profile in these tumor types. Bevacizumab has shown activity in patients with refractory metastatic RCC, where progression-free survival (PFS) was significantly longer in patients treated with bevacizumab (10 mg/kg every 2 weeks) than those treated with placebo (hazard ratio=2.55, p<0.001). In addition, combining bevacizumab with erlotinib (Tarceva) has shown a median time to progression of more than 11 months. In NSCLC, a phase II trial revealed that adding bevacizumab to chemotherapy increased therapeutic benefit compared with chemotherapy alone. Adverse events were mild and easily managed, but six patients receiving bevacizumab developed severe hemoptysis. Entry criteria for NSCLC trials have been adjusted to exclude patients with squamous cell histology to try to avoid this issue. Adding bevacizumab (10 mg/kg) to the current standard of care, gemcitabine, in stage IV pancreatic cancer has also shown promising efficacy. Partial responses were seen in 19% of patients, with a further 48% having stable disease. Several ongoing clinical trials are also studying bevacizumab with various chemotherapy and radiotherapy regimens. Bevacizumab combined with carboplatin (Paraplatin)/paclitaxel (Taxol) was further examined in a phase III randomized trial that accrued 878 patients with advanced non-squamous cell NSCLC. Patients given chemotherapy (paclitaxel and carboplatin) plus bevacizumab had a higher response rate, longer PFS and an increase in survival compared with patients on chemotherapy alone. Both regimens were generally well tolerated. Bevacizumab has also shown activity in patients with metastatic breast cancer. In 715 patients, a significant, 2-fold increase in response rate was observed in patients receiving bevacizumab plus paclitaxel compared with paclitaxel alone. Median PFS was also significantly increased (p<0.001). Bevacizumab has the potential to provide significant efficacy benefits for patients with metastatic RCC, NSCLC, pancreatic cancer, and other tumor types when used first line in combination with standard therapy.

Opinion: emerging mechanisms of tumour lymphangiogenesis and lymphatic metastasis

Malignant tumours can spread to lymph nodes through lymphatic vessels. Recent studies show that tumours produce a range of growth factors that directly or indirectly stimulate lymphatic vessel growth (lymphangiogenesis) and lymphatic metastasis. These findings indicate that tumour lymphangiogenesis, similar to haemangiogenesis, is a complex process that is regulated by multiple growth factors. Understanding the underlying mechanisms by which tumours induce lymphangiogenesis might provide important information for the therapeutic intervention of metastatic spread.

Hereditary pancreatic endocrine tumours

The two main types of hereditary pancreatic neuroendocrine tumours are found in multiple endocrine neoplasia type 1 (MEN-1) and von Hippel-Lindau disease (VHL), but also in the rarer disorders of neurofibromatosis type 1 and tuberous sclerosis. This review considers the major advances that have been made in genetic diagnosis, tumour localization, medical and surgical treatment and palliation with systemic chemotherapy and radionuclides. With the exception of the insulinoma syndrome, all of the various hormone excess syndromes of MEN-1 can be treated medically. The role of surgery however remains controversial ranging from no intervention (except enucleation for insulinoma), intervening for tumours diagnosed only by biochemical criteria, intervening in those tumours only detected radiologically (1-2 cm in diameter) or intervening only if the tumour diameter is > 3 cm in diameter. The extent of surgery is also controversial, although radical lymphadenectomy is generally recommended. Pancreatic tumours associated with VHL are usually non-functioning and tumours of at least 2 cm in diameter should be resected. Practice guidelines recommend that screening in patients with MEN-1 should commence at the age of 5 years for insulinoma and at the age of 20 years for other pancreatic neuroendocrine tumours and variously at 10-20 years of age for pancreatic tumours in patients with VHL. The evidence is increasing that the life span of patients may be significantly improved with surgical intervention, mandating the widespread use of tumour surveillance and multidisciplinary team management.

Expression and Localization of Hypoxia-Inducible Factor-1 Subunits in the Adult Rat Epididymis1

The epididymal epithelium contributes to formation of a luminal fluid that is essential for the protection of spermatozoa from a variety of insults including changes in oxygen tension. A key regulator of the response to oxygen debt in many cells is hypoxia-inducible factor-1 (HIF-1). A transcription factor composed of alpha and beta subunits, HIF-1 activates genes that mediate oxygen homeostasis and cell survival pathways or trigger cell death responses. Previously we have shown that HIF-1alpha mRNA is expressed in the adult rat epididymis. Goals of this study were to determine whether HIF-1alpha protein is activated by ischemia in the rat epididymis, to determine whether epididymal HIF-1alpha mRNA expression is androgen dependent, and to identify epididymal cell types expressing HIF-1alpha and beta. Immunoblot analysis revealed that HIF-1alpha protein is primarily present in corpus and cauda of the normoxic epididymis and unaffected by ischemia, whereas HIF-1beta was detected equally in all regions and also unaffected by ischemia. HIF-1alpha mRNA expression in all regions was not affected by 15 days bilateral orchiectomy. Principal cells stained positive for HIF-1alpha by immunocytochemistry, with the epithelium of initial segment and caput epididymidis staining less intensely than corpus and cauda. HIF-1beta immunoreactivity was equally present in principal cells in all regions. Clear, narrow, and basal cells were unreactive for HIF-1alpha and beta. The presence of HIF-1 in normoxic epididymis and the regional distribution of HIF-1alpha suggests fundamental differences in how proximal and distal regions of the epididymis maintain oxygen homeostasis to protect the epithelium and spermatozoa from hypoxia.

Endolymphatic sac tumor (low-grade papillary adenocarcinoma) of the temporal bone

The entity which has come to be known as an endolymphatic sac tumor (ELST) has, in the past, been known as adenocarcinoma of endolymphatic sac origin, aggressive papillary tumor of the temporal bone and Heffner's tumor. ELSTs arise in the vicinity of the inner ear and may extend to involve both the posterior fossa as well as the middle ear and the external ear canal, which may complicate the differential diagnosis ELSTs are typically seen in adults, with only rare descriptions in pediatric patients. They may be sporadic tumors or they may arise as part of the symptom complex of von Hippel-Lindau disease. Clinical signs at presentation range from a mass in the external ear canal to sensorineural deafness to cranial nerve palsies. Imaging studies reveal a destructive lesion of the petrous bone which is heterogeneous on MR scanning. Light microscopy reveals two chief patterns: a follicular pattern, reminiscent of thyroid parenchyma; and a papillary/solid pattern. Both patterns are often admixed in the same tumor, and the individual tumor cells are cytologically bland. Immunohistochemically, ELSTs are typically keratin-, vimentin- and epithelial membrane antigen-positive; they are often S-100 protein-positive and neuron-specific enolase-positive as well. ELSTs are difficult to extirpate surgically (owing to their locally aggressive nature); nevertheless, surgical excision remains the mainstay of current therapy. These are slow-growing (albeit locally aggressive) tumors which have only rarely been reported to metastasize; as such, they remain principally a problem of local control.