Bilateral papillary cystadenoma of the mesosalpinx: a rare manifestation of Von Hippel-Lindau disease

An optimized protocol for evaluating pathogenicity of VHL germline variants in patients suspected with von Hippel-Lindau syndrome: Using somatic genome to inform the role of germline variants

The interpretation of hereditary genetic sequencing variants is often limited due to the absence of functional data and other key evidence to assess the role of variants in disease. Cancer genetics is unique, as two sets of genomic information are often available from a cancer patient: somatic and germline. Despite the progress made in the integrated analysis of somatic and germline findings, the assessment of pathogenicity of germline variants in high penetrance genes remains grossly underutilized. Indeed, standard ACMG/AMP guidelines for interpreting germline sequence variants do not address the evidence derived from tumor data in cancer. Previously, we have demonstrated the utility of somatic tumor data as supporting evidence to elucidate the role of germline variants in patients suspected with VHL syndrome and other cancers. We have leveraged the key elements of cancer genetics in these cases: genes with expected high disease penetrance and those with a known biallelic mechanism of tumorigenicity. Here we provide our optimized protocol for evaluating the pathogenicity of germline VHL variants using informative somatic profiling data. This protocol provides details of case selection, assessment of personal and family evidence, somatic tumor profiles, and loss of heterozygosity (LOH) as supporting evidence for the re-evaluation of germline variants.

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.

Pathogenicity of VHL variants in families with non-syndromic von Hippel-Lindau phenotypes: An integrated evaluation of germline and somatic genomic results

Von Hippel-Lindau (VHL) syndrome is a hereditary tumor syndrome associated with germline loss-of-function pathogenic variants (PVs) in the VHL gene. VHL is classically associated with a high penetrance for many different tumor types. The same tumors may be sporadic in the setting of somatic VHL PVs. With more large-scale genome sequencing, variants with low penetrance or variable expressivity are identified. This has introduced challenges in patient management and the clinical interpretation of germline VHL variants identified in non-classic families. Herein, we report individuals from 3 non-classic families with VHL variants who presented with unexpected or non-syndromic phenotypes, but often with a VHL component tumor. In family 1, two siblings, age 61, with pathogenic VHL p.Leu188Val presented with clear cell renal cell carcinoma and lobular breast cancer. In family 2, the proband, age 82, was found to have pathogenic germline VHL p.Tyr98His on testing for metastatic bladder cancer. In family 3, four members carried germline VHL p.Pro81Ser (variant of uncertain significance), after the proband, age 40, presented with cerebellar hemangioblastoma. None of the individuals in the above three families met clinical criteria of classic VHL, suggesting germline VHL p.Leu188Val, p.Y98H, and p.Tyr98His may be low penetrant variants. Large studies are needed to evaluate penetrance and possible effect of genetic and non-genetic modifiers. Somatic sequencing performed on their respective tumors could help discern the etiology of the component tumors, highlighting the role of somatic evaluation in these cases. Paired examination of somatic and germline findings provided a more complete landscape of genome alterations in cancer development.

Papillary Cystadenoma: An Incidental Finding in Tubal Ligation

von Hippel-Lindau disease (vHLD) is a rare autosomal dominant disorder with multiple benign and malignant tumors of different organs. We report a papillary cystadenoma of the mesosalpinx found in close association with an adenomatoid tumor discovered incidentally following tubal ligation in a patient with vHLD.

Gynecologic Manifestations of Less Commonly Encountered Hereditary Syndromes

This review covers gynecologic manifestations that may occur in rare hereditary syndromes. Recent advances in disorders, such as hereditary leiomyomatosis, renal cell carcinoma syndrome and tuberous sclerosis complex, are discussed as well as lesions that occur in von Hippel-Lindau syndrome, nevoid basal cell carcinoma syndrome, Cowden syndrome, Ollier disease/Maffucci syndrome, and Carney complex. Characteristic clinicopathologic features of each of these syndromes are discussed with an emphasis on the key features that enable pathologists to identify patients at highest risk for these diseases.

Von Hippel-Lindau disease

von Hippel-Lindau (VHL) disease is an inheritable condition with an incidence of 1 in 36000 live births. Individuals with VHL develop benign and malignant tumors including retinal and central nervous system hemangioblastomas, clear cell renal cell carcinomas (RCC), pheochromocytomas, pancreatic neuroendocrine tumors and endolymphatic sac tumors (ELSTs). VHL is caused by germline loss of function of the VHL gene on one allele at chromosome 3p25-26. A somatic "second hit" event leads to the loss of the other allele and tumor formation. Loss of VHL function in cells leads to increased expression and stabilization of hypoxia inducible factor (HIF). VHL protein/HIF pathway has been implicated in tumorigenesis for hemangioblastomas, RCC and other VHL tumors. Clinical examination, imaging, and genetic testing for VHL mutations confirm VHL disease. Management of VHL disease largely consists of surgical resection of symptomatic tumors (hemangioblastomas), tumors prone to metastasize (RCC larger than 3cm), or tumors causing hormonal symptoms (pheochromocytomas). Despite advances in early diagnosis and management of VHL disease, life expectancy for VHL patients remains low at 40-52 years. Secondary effects from VHL manifestations are mitigated by routine surveillance and early detection. In this chapter, we summarize the current state of knowledge in VHL disease.

An analysis of five clear cell papillary cystadenomas of mesosalpinx and broad ligament: four associated with von Hippel-Lindau disease and one aggressive sporadic type

AIMS

Clear cell papillary cystadenoma (CCPC) is associated with von Hippel-Lindau disease (VHLD), but rarely involves mesosalpinx and broad ligament (M/BL). This study provides new data about its behaviour and immunophenotype.

METHODS AND RESULTS

We performed an analysis of four benign cases of CCPC of M/BL with either characteristic clinical features or genetic markers [loss of heterozygosity (LOH)] of VHLD in patients ranging from 24 to 36 years and a sporadic case in a 52-year-old presenting with peritoneal metastases. All CCPCs were papillary but had solid and tubular areas. Haemorrhage, thrombosis and scarring were constant features and related to an unusual pattern of sub-epithelial vascularity. All clear or oxyphilic cells co-expressed cytokeratin 7 (CK7), CAM5.2 and vimentin, with strong apical CD10 and nuclear paired box gene 2 (PAX2) immunoreactivity. Three cases also showed positivity for VHL40, epithelial membrane antigen (EMA), Wilms' tumour suppressor gene (WT-1) and cancer antigen 125 (CA125) but only one expressed renal cell carcinoma (RCC) antigen. Vascular plexus overexpressed nuclear and cytoplasmic WT-1.

CONCLUSION

The VHLD-associated cases appeared to be benign, but the sporadic case exhibited a low malignant potential. CCPCs show histological and immunophenotypical similarities with the recently reported clear cell papillary RCC, although the previously unreported apical CD10 and nuclear PAX2 expression may be related to their mesonephric origin. CCPC has a distinctive sub-epithelial vascular pattern that is consistent with its pathogenesis.

von Hippel-Lindau disease: a clinical and scientific review

The autosomal dominantly inherited disorder von Hippel-Lindau disease (VHL) is caused by germline mutations in the VHL tumour suppressor gene (TSG). VHL mutations predispose to the development of a variety of tumours (most commonly retinal and central nervous system haemangioblastomas, clear cell renal carcinoma and phaeochromocytomas). Here, we review the clinical and genetic features of VHL disease, briefly review the molecular pathogenesis and outline clinical management and tumour surveillance strategies.