[Clinical status of Von Hippel-Lindau disease associated pheochromocytoma in Japan: a national epidemiologic survey]

A Case of Von Hippel-Lindau Disease With Recurrence of Paraganglioma and No Other Associated Symptoms: The Importance of Genetic Testing and Establishing Follow-Up Policies

Pheochromocytoma and paraganglioma (PPGL) are rare neuroendocrine tumors. Catecholamine production by the tumors leads to high blood pressure. Although most PPGLs are benign, some have metastatic potential. Almost half of PPGLs are caused by germline mutations, and the causative genes are diverse. Von Hippel-Lindau disease (VHL) is an autosomal dominant multisystem tumor predisposition syndrome characterized by central nervous system and retinal hemangioblastomas, clear cell renal cell carcinoma, pancreatic neuroendocrine tumors, and PPGLs. Sometimes VHL presents only as paraganglioma (PGL), making its diagnosis difficult. A male child aged five years and one month was found to have isolated catecholamine-producing PGL in the right renal hilum during evaluation for hypertension. The patient was completely cured by tumor resection, and somatic mutation testing of the tumor revealed no abnormalities. At the age of nine years and 11 months, the patient had a recurrence of PGL in the left border of the abdominal aorta. Comprehensive germline genetic testing was performed and revealed a pathologic missense variant NM_000551.4:c.482G>A p.(Arg161Gln) in the VHL gene. This variant showed loss of heterozygosity in both primary and recurrent tumors by Sanger sequencing, and DNA microarray analysis revealed a monosomy of the entire chromosome 3 where VHL is located. Arg161Gln has been previously reported in several other VHL families, and the symptoms were diverse beyond PPGLs. This case demonstrates the importance of genetic diagnosis with VHL in mind. It was also recognized that this patient needed to be followed for symptoms of VHL other than PGL.

Investigation of germline VHL variants in Iranian patients with retinal capillary hemangioblastoma and genotype-phenotype analysis

BACKGROUND

Retinal capillary hemangioblastoma (RCH), while sporadic in some cases, is the most common and earliest manifestation of von Hippel-Lindau disease (VHL). This is the first report on different types of VHL variants and genotype-phenotype correlations in Iranian families with RCH.

MATERIALS AND METHODS

In this prospective observational case series study, 17 families with RCH were included. PCR was performed to amplify 3 exons of VHL gene. Afterward, Sanger sequencing was performed on all PCR products. For the detection of VHL copy number variations, MLPA was used.

RESULTS

Our study identified 10 different types of VHL variants. Missense mutations were the most common variants found and affected the structure of α domain of the VHL protein (pVHL). The majority of mutations (72.7%) in the patients with RCH and central nervous system hemangioblastoma (CNS-HB) were located on α domain.

CONCLUSION

α domain of VHL may play a potential role in the pathogenesis of RCH. Our findings suggest that genotype-phenotype characteristics in those variants in α- domain may predispose patients to RCH with CNS-HB.

Shorter telomere length increases age-related tumor risks in von Hippel-Lindau disease patients

Von Hippel-Lindau (VHL) disease is a rare autosomal dominant cancer syndrome caused by alterations of VHL gene. Patients are predisposed to develop pheochromocytomas and solid or cystic tumors of the central nervous system, kidney, pancreas, and retina. Remarkable phenotypic heterogeneity exits in organ involvement and tumor onset age between and within VHL families. However, no reliable markers have been found to predict the age-related tumor risks in VHL patients. A large Chinese cohort composed of 300 VHL patients and 92 healthy family controls was enrolled in our study. Blood relative telomere length was measured in 184 patients and all the controls available for genomic DNA samples. Age-related risks for the five major VHL-associated tumors were evaluated using Kaplan-Meier plots and Cox regression analysis. Differences in clinical phenotype were observed between Chinese cohort and the United Kingdom cohort. VHL patients showed significantly shorter telomere length than healthy family controls(P = 0.0183), and a positive correlation was found between telomere length and onset age of the five major tumors, respectively. Moreover, patients in the shorter telomere group (age-adjusted telomere length ≤ 0.44) suffered higher age-related risks for VHL-associated central nervous system hemangioblastomas (HR: 1.879, P = 0.004), renal cell carcinoma (HR: 2.126, P = 0.002) and pancreatic cyst and neuroendocrine tumors (HR: 2.093, P = 0.001). These results indicate that blood shorter telomere length is a new biomarker for age-related tumor risks in VHL patients, which will be crucial to genetic counseling and future research about the role of telomere shortening in the pathogenesis of VHL-associated tumors.

Development of Database and Genomic Medicine for von Hippel-Lindau Disease in Japan

von Hippel-Lindau (VHL) disease is a hereditary tumor disease in which tumors develop in multiple organs, not only as hemangioblastomas (HBs) in the central nervous system, but also as kidney tumors, pheochromocytomas, and so on. Much about the epidemiology of VHL disease remained unknown until fairly recently in Japan, leading to calls for the establishment of a VHL disease epidemiological database in Japanese. To elucidate its epidemiology in Japan, the Japanese Ministry of Health, Labour and Welfare created the VHL Disease Study Group, which was put in charge of carrying out a nationwide epidemiological survey. The survey found close to 400 Japanese VHL disease patients throughout the country. Based on those results, the VHL Disease Study Group created the VHL Disease Treatment Guideline and also a severity classification. It is thought that the prognosis of VHL disease patients can be improved by performing genetic diagnosis and careful follow-up. Accordingly, the University of Tokyo Hospital put in place an in-hospital system for implementing genomic medicine for VHL disease based on genetic diagnosis. For that system, it was especially important to establish (I) accurate genetic diagnostic techniques, (II) genetic counseling capabilities for the patients and their families, and (III) a system of cooperation among multiple departments, including urology departments, and so on. Further elucidation of the epidemiology and the development of genomic medicine are needed to improve the treatment results of VHL disease in Japan.

Clinical and molecular characteristics of East Asian patients with von Hippel-Lindau syndrome

Background

Von Hippel–Lindau (VHL) syndrome is a dominantly inherited multisystem cancer syndrome caused by a heterozygous mutation in the VHL tumor suppressor gene. Previous studies suggested that similar populations of Caucasian and Japanese patients have similar genotype or phenotype characteristics. In this comprehensive study of East Asian patients, we investigated the genetic and clinical characteristics of patients with VHL syndrome.

Methods

To create a registry of clinical characteristics and mutations reported in East Asian patients with VHL syndrome, we conducted a comprehensive review of English language and non-English language articles identified through a literature search. Publications in Japanese or Chinese language were read by native speakers of the language, who then performed the data extraction.

Results

Of 237 East Asian patients with VHL syndrome, 154 unique kindreds were identified for analysis. Analyzed by kindred, missense mutations were the most common (40.9%, 63/154), followed by large/complete deletions (32.5%, 50/154) and nonsense mutations (11.7%, 18/154). Compared with a previously reported study of both East Asian and non-East Asian patients, we found several key differences. First, missense and frameshift mutations in the VHL gene occurred less commonly in our population of East Asian patients (40.9% vs. 52.0%; P = 0.012 and 8.4% vs. 13.0%; P < 0.001, respectively). Second, large/complete deletions were more common in our population of East Asian patients (32.5% vs. 10.5%; P < 0.001). Third, phenotypically, we observed that, in our population of East Asian patients with VHL syndrome, the incidence of retinal capillary hemangioblastoma was lower, whereas the incidence of renal cell carcinoma was higher.

Conclusions

Evidence suggests that the genotypic and phenotypic characteristics of East Asian patients with VHL syndrome differ from other populations. This should be considered when making screening recommendations for VHL syndrome in Asia.

Electronic supplementary material

The online version of this article (doi:10.1186/s40880-016-0141-z) contains supplementary material, which is available to authorized users.

Genotype-phenotype analysis of von Hippel-Lindau syndrome in Korean families: HIF-α binding site missense mutations elevate age-specific risk for CNS hemangioblastoma

BACKGROUND

von Hippel-Lindau (VHL) disease is a rare hereditary tumor syndrome caused by VHL gene mutations that is characterized by heterogeneous phenotypes such as benign/malignant tumors of the central nervous system, retina, kidney, adrenal gland, and pancreas. The genotype-phenotype correlation has not been well characterized in the Korean population so far. Therefore, this study aimed to evaluate the VHL mutation spectrum and genotype-phenotype correlations in Korean VHL patients.

METHODS

Thirteen unrelated subjects with VHL mutations were included. Direct sequencing and multiplex ligation-dependent probe amplification were performed. Consequently, the clinical manifestations and family histories of the subjects were evaluated.

RESULTS

We identified 10 different VHL mutations. The c.160_161delAT frameshift mutation was novel. Missense mutations clustered in 2 domains (α domain in exon 1; β domain in exon 3). The most frequently observed mutation was c.208G > A (p.Glu70Lys). Milder phenotypes were observed in subjects with de novo mutations. Age-specific risk for CNS hemangioblastoma was significantly higher in subjects carrying missense mutations within the HIF-α binding site (P < 0.05).

CONCLUSIONS

This study provides insight into the genotype-phenotype correlation in that amino acid substitutions in the HIF-α binding site may predispose patients to age-related risks of CNS hemangioblastoma.