Hereditary leiomyomatosis and renal cell carcinoma

Hereditary Leiomyomatosis and Renal Cell Cancer

Hereditary leiomyomatosis and renal cell cancer is a genodermatosis with an autosomal dominant inheritance pattern. It is a tumour predisposition syndrome characterized by cutaneous and uterine leiomyomas, and increased susceptibility to develop renal cell carcinoma. There are 200-300 families with hereditary leiomyomatosis and renal cell carcinoma reported worldwide, but the syndrome is believed to be underdiagnosed. Cutaneous leiomyomas are small smooth muscle tumours that tend to grow over time. Larger lesions, in particular, can cause pain or itching. Uterine leiomyomas have a high penetrance in women with hereditary leiomyomatosis and renal cell cancer. They frequently cause symptoms, and surgical intervention is often necessary. Hereditary leiomyomatosis and renal cell cancer-associated renal cell carcinomas have a high potential to metastasize. Patients are diagnosed by genetic testing if a pathogenic mutation is demonstrated in the gene encoding fumarate hydratase. Immunohistochemistry may be a useful diagnostic approach in patients without a detectable pathogenic mutation. Diagnosed patients should be monitored for renal tumours in a lifelong surveillance programme.

Rescue of TCA Cycle Dysfunction for Cancer Therapy

Mitochondrion, a maternally hereditary, subcellular organelle, is the site of the tricarboxylic acid (TCA) cycle, electron transport chain (ETC), and oxidative phosphorylation (OXPHOS)—the basic processes of ATP production. Mitochondrial function plays a pivotal role in the development and pathology of different cancers. Disruption in its activity, like mutations in its TCA cycle enzymes, leads to physiological imbalances and metabolic shifts of the cell, which contributes to the progression of cancer. In this review, we explored the different significant mutations in the mitochondrial enzymes participating in the TCA cycle and the diseases, especially cancer types, that these malfunctions are closely associated with. In addition, this paper also discussed the different therapeutic approaches which are currently being developed to address these diseases caused by mitochondrial enzyme malfunction.

Fumaratehydratase-deficient renal cell carcinoma: a clinicopathological and molecular study of 13 cases

Aims

Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) is a newly recognised entity in the WHO 2016 classification defined as the germline mutation of FH gene. Fumaratehydratase-deficient renal cell carcinoma (FH-deficient RCC) is recommended for tumours with FH deficiency but lacking of genetic evidences of FH germline mutation. In this study, we described the clinicopathological and molecular changes of 13 FH-deficient RCCs.

Methods and results

Histology features, clinicopathological data, radiology performance and outcomes were collected for each patient. Next-generation sequencing and DNA sequencing of FH gene were performed to examine FH mutations. The patient group included five females and eight males. Different morphological patterns of papillary, nested, adenoid, foam adenoid, cribriform, tubular, tubulocystic, cystic and loose oedema stroma were observed. Except typical big nuclei with or without eosinophilic nucleoli and perinucleolar halos, raisin-like, hobnail-like and even low-grade nuclei were also observed in these tumours. Eleven cases with high-grade nuclei showed disease progression or death, but no disease progression was detected in two cases with low-grade nuclei and eosinophilic cytoplasm. FH expression was absent in tumour cells except for case 11. Next-generation sequencing and DNA sequencing verified seven FH germline mutations and four somatic mutations out of 13 cases.

Conclusions

FH-deficient RCC is a rare renal tumour and has a wide morphological spectrum. Most of the tumours had high-grade nuclei and were aggressive. However, we observed a morphological subtype of FH-deficient RCC with low-grade nuclei and eosinophilic cytoplasm, which might mainly occur in young women and show a relatively good prognosis.

Long-term response of metastatic hereditary leiomyomatosis and renal cell carcinoma syndrome associated renal cell carcinoma to bevacizumab plus erlotinib after temsirolimus and axitinib treatment failures

BACKGROUND

Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) is a rare hereditary kidney cancer syndrome in which affected individuals are at risk of skin and uterine leiomyomatosis and kidney cancer. HLRCC-associated kidney cancer is a lethal disease with a highly aggressive behavior, and there is no standard treatment option for metastatic disease.

CASE PRESENTATION

Here, we report a 29-year-old patient with a locally advanced HLRCC-assiciated RCC. He was administrated temsirolimus initially, then underwent surgical removal of kidney, retroperitoneal lymph nodes, inferior vena cava and tumor thrombi. Unfortunately, multiple liver metastases were confirmed 1 month after surgery, so axitinib was given but failed immediately. We tried bevacizumab plus erlotinib, which achieved long-term good response lasting more than 18 months. He is alive with disease and maintains bevacizumab plus erlotinib treatment.

CONCLUSION

The promising results obtained in this patient suggest that combined bevacizumab plus erlotinib may offer a valid treatment option for advanced HLRCC-associated kidney cancer, even after failures of mTOR inhibitor and/or VEGFR TKI based therapies.

Suppression of fumarate hydratase activity increases the efficacy of cisplatin-mediated chemotherapy in gastric cancer

Gastric cancer (GC) is one of the most common malignancies worldwide. Due to the low rate of early detection, most GC patients were diagnosed as advance stages and had poor response to chemotherapy. Some studies found that Fumarate hydratase (FH) participated in the DNA damage response and its deficiency was associated with tumorigenesis in some cancers. In this study, we investigated the relationship between FH and cisplatin (CDDP) sensitivity in GC cell lines. We found that FH was the most significant gene which induced by CDDP treatment and the suppression of FH could enhance the cytotoxicity of CDDP. Miconazole Nitrate (MN) could inhibit FH activity and enhance the effect of CDDP in vitro and in vivo. We also investigated the significance of expression of FH in GC tissues. The FH expression, which was higher in GC tissues than in noncancerous tissues, was negatively associated with the prognosis of patients. Together, these results revealed that FH is a reliable indicator for response to CDDP treatment in GC and the inhibition of FH may be a potential strategy to improve the effects of CDDP-based chemotherapy.

Fumarate hydratase in cancer: A multifaceted tumour suppressor

Cancer is now considered a multifactorial disorder with different aetiologies and outcomes. Yet, all cancers share some common molecular features. Among these, the reprogramming of cellular metabolism has emerged as a key player in tumour initiation and progression. The finding that metabolic enzymes such as fumarate hydratase (FH), succinate dehydrogenase (SDH) and isocitrate dehydrogenase (IDH), when mutated, cause cancer suggested that metabolic dysregulation is not only a consequence of oncogenic transformation but that it can act as cancer driver. However, the mechanisms underpinning the link between metabolic dysregulation and cancer remain only partially understood. In this review we discuss the role of FH loss in tumorigenesis, focusing on the role of fumarate as a key activator of a variety of oncogenic cascades. We also discuss how these alterations are integrated and converge towards common biological processes. This review highlights the complexity of the signals elicited by FH loss, describes that fumarate can act as a bona fide oncogenic event, and provides a compelling hypothesis of the stepwise neoplastic progression after FH loss.

Multiple unilateral subcapsular cortical hemorrhagic cystic disease of the kidney: CT and MRI findings and clinical characteristic

PURPOSE

The aim of this study was to clarify the radiologic and clinical characteristics of multiple unilateral subcapsular cortical hemorrhagic cystic disease of the kidney.

METHOD

Fourteen patients with unique and characteristic multiple hemorrhagic subcapsular cortical cysts of the kidney, not categorized in any existing renal cystic diseases, were retrospectively reviewed. The clinical information including age, sex, symptom, family history of renal or renal cystic disease, and laboratory data were collected. CT and MRI findings including distribution, number and size of cysts, and CT attenuation and signal intensity on T1- and T2-weighted MRI of cysts were analyzed.

RESULTS

All patients except one were young and none had a family history of renal or renal cystic disease. Common clinical symptoms were flank or abdominal pain and hematuria. In all cases, only the left kidney was involved at initial presentation. Cysts were small (median cyst size, 4-15 mm), numerous, and distributed mainly along the subcapsular cortex of the kidney. Cysts were hyper-attenuated on unenhanced CT, extremely hypointense on T2-weighted MRI, and mildly hyperintense on T1-weighted MRI. All patients except one had normal renal function. Imaging follow-up revealed stable or mildly progressive disease in seven patients. Two patients developed several hemorrhagic subcapsular cortical cysts in the right kidney at follow-up. Three of five patients with a renal pathology specimen showed concurrent IgA nephropathy.

CONCLUSION

We have identified a unique renal cystic disease with multiple unilateral subcapsular cortical hemorrhagic cystic disease of the kidney that has a characteristic manifestation both radiologically and clinically.

KEY POINTS

• Multiple unilateral subcapsular cortical hemorrhagic cystic disease of the kidney is a unique non-familial renal cystic disease with a characteristic manifestation both radiologically and clinically. • Most cases of multiple unilateral subcapsular cortical hemorrhagic cystic disease of the kidney are stable or slowly progressive, and do not require invasive intervention.

Germline mutations of renal cancer predisposition genes and clinical relevance in Chinese patients with sporadic, early-onset disease

BACKGROUND

An inherited susceptibility to renal cancers is associated with multiple predisposing genes, but most screening tests are limited to patients with a family history. Next-generation sequencing (NGS)-based multigene panels provide an efficient and adaptable tool for investigating pathogenic germline mutations on a larger scale. This study investigated the frequency of pathogenic germline mutations in renal cancer predisposition genes in patients with sporadic, early-onset disease.

METHODS

An NGS-based panel of 23 known and potential renal cancer predisposition genes was used to analyze germline mutations in 190 unrelated Chinese patients under the age of 45 years who presented with renal tumors. The detected variants were filtered for pathogenicity, and then their frequencies were calculated and correlated with clinical features. Germline variants of the fumarate hydratase (FH) and BRCA1-associated protein 1 (BAP1) genes were comprehensively analyzed because of their aggressive potential.

RESULTS

In total, 18 patients (9.5%) had germline mutations in 10 genes. Twelve of these 18 patients had alterations in renal cancer predisposition genes (6.3%), and 6 patients had mutations in potential predisposition genes such as BRCA1/2. Notably, pathogenic mutation carriers had a significant family history in second-degree relatives in comparison with those without pathogenic mutations (P < .001). Variants of unknown clinical significance in FH and BAP1 demonstrated evidence of additional somatic loss in tumors.

CONCLUSIONS

In patients with early-onset disease, a multigene panel identified a high pathogenic germline mutation rate in renal cancer predisposition genes. This study emphasizes the importance of screening patients with early-onset disease for mutations in cancer predisposition genes. Germline screening should be encouraged in early-onset patients to provide personalized medicine and improve patient outcomes.

Translating genomic risk into an early detection strategy for sarcoma

Sarcomas have a strong genetic etiology, and the study of families affected by sarcomas has informed much of what we now understand of modern cancer biology. The recent emergence of powerful genetic technologies has led to astonishing reductions in costs and increased throughput. In the clinic, these technologies are revealing a previously unappreciated and rich landscape of genetic cancer risk. In addition to both known and new cancer risk mutations, genomic tools are cataloguing complex and polygenic risk patterns, collectively explaining between 15-25% of apparently sporadic sarcoma cases. The impact on clinical management is exemplified by Li-Fraumeni Syndrome, the most penetrant sarcoma syndrome. Whole body magnetic resonance imaging can identify surgically resectable cancers in up to one in ten individuals with Li-Fraumeni Syndrome. Taken together, parallel developments in genomics, therapeutics and imaging technologies will drive closer engagement between genetics and multidisciplinary care of the sarcoma patient in the 21st century.

Gene expression analysis in peripheral blood cells of patients with hereditary leiomyomatosis and renal cell cancer syndrome (HLRCC): identification of NRF2 pathway activation

Hereditary leiomyomatosis and renal cell cancer syndrome (HLRCC) is a very rare disease that is inherited in an autosomal dominant manner. Affected patients may develop from cutaneous and uterine leiomyomas to type 2 papillary renal cell carcinoma (Schmidt and Linehan, Int J Nephrol Renovasc Dis 7:253-260, 2014). HLRCC is caused by germline mutations in the FH gene, which produces the fumarate hydratase protein that participates in the tricarboxylic acid cycle during the conversion of fumarate to malate. In FH-deficient cells, high concentrations of fumarate lead to a series of intricate events, which seem to be responsible for the malignant transformation (Yang et al., J Clin Invest 123(9):3652-3658, 2013) (Bardella et al., J Pathol 225(1):4-11, 2011). Among these events, one that is gaining attention is the pathological activation of the nuclear factor erythroid 2-related factor 2 (NRF2) pathway, which has been found in several types of cancer and is implicated in the expression of genes associated with antioxidant responses (Linehan and Rouault, Clin Cancer Res 19(13):3345-3352, 2013). In this article, we present the results of a gene expression analysis performed on peripheral blood cells from patients with HLRCC syndrome, where upregulation of numerous NRF2 targets and the differential expression of two key genes, Jun dimerization protein 2 (JDP2) and Phosphoglycerate mutase family member 5 (PGAM5), which are involved in the control of this pathway, was observed.

Genetics of primary macronodular adrenal hyperplasia

Recent advances in molecular genetics investigations of primary macronodular adrenal hyperplasia (PMAH) have been providing new insights for the research on this issue. The cAMP-dependent pathway is physiologically triggered by ACTH and its receptor, MC2-R, in adrenocortical cells. Different mechanisms of this cascade may be altered in some functioning adrenal cortical disorders. Activating somatic mutations of the GNAS gene (known as gsp oncogene) which encodes the stimulatory G protein alpha-subunit (Gsα) have been found in a small number of adrenocortical secreting adenomas and rarely in PMAH. Lately, ARMC5 was linked to the cyclic AMP signaling pathway, which could be implicated in all of mechanisms of cortisol-secreting by macronodules adrenal hyperplasia and the molecular defects in: G protein aberrant receptors; MC2R; GNAS; PRKAR1A; PDE11A; PDE8B. Around 50 % of patient's relatives with PMAH and 30 % of apparently sporadic hypercortisolism carried ARMC5 mutations. Therefore, PMAH is genetically determined more frequently than previously believed. This review summarizes the most important molecular mechanisms involved in PMAH.

Metabolome-guided genomics to identify pathogenic variants in isocitrate dehydrogenase, fumarate hydratase, and succinate dehydrogenase genes in pheochromocytoma and paraganglioma

Purpose:

Metabolic aberrations have been described in neoplasms with mutations in the Krebs cycle genes encoding succinate dehydrogenase (SDH), fumarate hydratase (FH) and isocitrate dehydrogenase (IDH). In turn, accumulation of oncometabolites succinate, fumarate, and 2-hydroxyglutarate can be employed to identify tumors with those mutations. Additionally, such metabolic readouts may aid in genetic variant interpretation and improve diagnostics.

Methods:

Using liquid-chromatography-mass-spectrometry, 395 pheochromocytomas and paragangliomas (PPGLs) from 391 patients were screened for metabolites to indicate Krebs cycle aberrations. Multi-gene panel-sequencing was applied to detect driver mutations in cases with indicative metabolite profiles but undetermined genetic drivers.

Results:

Aberrant Krebs cycle metabolomes identified rare cases of PPGLs with germline mutations in FH and somatic mutations in IDHx and SDHx, including the first case of a somatic IDH2 mutation in PPGL. Metabolomics also reliably identified PPGLs with SDHx loss-of-function (LOF) mutations. Therefore we utilized tumor metabolite profiles to further classify variants of unknown significance in SDHx, thereby enabling missense-variants associated with SDHx LOF to be distinguished from benign variants.

Conclusion:

We propose incorporation of metabolome data into the diagnostics algorithm in PPGLs to guide genetic testing and variant interpretation and to help identify rare cases with mutations in FH and IDHx.

Reed's Syndrome

Multiple cutaneous and uterine leiomyomatosis (MCUL), also known as Reed's syndrome, is a rare genodermatosis, with an autosomal dominant pattern of inheritance. It results from a germline heterozygous mutation of fumarate hydratase gene, that is classified as a tumor suppressor gene. Hereditary leiomyomatosis and renal cell cancer is characterized by the association of MCUL with renal cell carcinoma. We report a case of a 57-year-old woman, with multiple cutaneous leiomyomas as the presenting sign of Reed's syndrome.

High grade infiltrative adenocarcinomas of renal cell origin: New insights into classification, morphology, and molecular pathogenesis

Collecting duct carcinoma was described over 30 years ago as a renal tumor, based in the medullary collecting system, with tubulopapillary morphology, prominent infiltrative growth, and stromal desmoplasia. While diagnostic workup has always emphasized exclusion of upper tract urothelial carcinoma and metastatic adenocarcinoma to the kidney, the molecular era of renal cell carcinoma classification has enabled recognition of and provided tools for diagnosis of new entities in this morphologic differential. In this review, we consider these developments, with emphasis on renal medullary carcinoma, closely related renal cell carcinoma, unclassified with medullary phenotype, and fumarate hydratase-deficient renal cell carcinoma. Integration of ancillary studies with suggestive patterns of morphology is emphasized for practical implementation in contemporary diagnosis, and several emerging tumor types in the morphologic differential are presented.

Hereditary leiomyomatosis and renal cell cancer: Cutaneous lesions & atypical fibroids

Objective

To report a diagnosis of hereditary leiomyomatosis and renal cell cancer (HLRCC) syndrome following initial presentation with multiple cutaneous lesions.

Design

Case report.

Design classification

N/A.

Setting

Academic tertiary care center.

Patient(s)

27-year-old nulligravid woman who presented with multiple red-brown lesions on her skin found to have cutaneous and uterine leiomyoma.

Intervention(s)

Biopsy of cutaneous lesions and fertility sparing robot-assisted laparoscopic myomectomy (RALM).

Main outcome measures(s)

Histological assessment of uterine leiomyoma.

Results(s)

Pathologic examination of uterine leiomyoma revealed diffuse atypia and fumarate hydratase loss phenotype concerning for genetic syndrome. Follow-up DNA sequencing via Sanger sequencing confirmed a pathogenetic R2333H mutation consistent with HLRCC.

Conclusion(s)

Consideration of HLRCC on differential diagnosis when patients present with cutaneous nodules and atypical or early onset uterine leiomyoma provides opportunity for early surveillance, family member testing, and more thoughtful surgical planning.

Precis

27-year-old woman with multiple cutaneous lesions is found to have uterine leiomyomas and undergoes robotic myomectomy. Genetic testing of uterine leiomyomas reveals mutation in fumarate hydratase, etiologic in hereditary leiomyomatosis and renal cell cancer (HLRCC).

•

Atypical skin findings and fibroids warrant consideration of HLRCC on the differential diagnosis.

•

Consider similar genetic testing and management as those with Lynch syndrome associated endometrial cancer.

•

Pre-operative planning should take HLRCC into consideration when considering tissue containment and removal strategies.

Re-evaluation of 33 'unclassified' eosinophilic renal cell carcinomas in young patients

AIMS

We sought to determine if some unclassified renal cell carcinomas (RCCs) in children and young adults that are characterised by predominantly eosinophilic cytoplasm are related to the recently described succinate dehydrogenase (SDH)-deficient RCC, fumarate hydratase (FH)-deficient RCC or eosinophilic solid and cystic (ESC) RCC.

METHODS AND RESULTS

We reviewed 33 unclassified RCCs with predominantly eosinophilic cytoplasm in patients aged 35 years or younger. Immunohistochemistry (IHC) for SDHB, FH and CK20 (a marker of ESC) was performed in all cases. IHC for 2-succinocysteine (2SC) was performed on RCC with loss of FH labelling. Four RCC (12%) (median age 18 years) demonstrated loss of FH labelling as well as aberrant 2SC labelling, and were thus classified as FH-deficient RCCs. Importantly, none of these cases demonstrated the characteristic macronucleoli typical of FH-deficient RCC. Eight RCC (24%) (median age 20.5 years) demonstrated loss of SDHB and were reclassified as SDH-deficient RCCs. Importantly, only four of eight SDH-deficient RCC demonstrated the characteristic cytoplasmic vacuoles and inclusions of typical SDH-deficient RCC. Ten RCC (30%) (median age 27 years) were reclassified as ESC RCCs. Four of 10 ESC RCC were multifocal (one bilateral), four of 10 ESC RCC occurred in males and one patient presented with liver and lung metastases, all not described previously in ESC. Eleven RCC (33%) remained unclassified.

CONCLUSIONS

Pathologists should have a low threshold for performing FH, SDHB and CK20 IHC when confronted with unclassified eosinophilic RCC or 'oncocytoma' in young patients.

Morphological clues to the appropriate recognition of hereditary renal neoplasms

An important emerging role of the surgical pathologist besides the traditional tasks of establishment of the diagnosis and documentation of prognostic and predictive factors, is to recognize the possibility of a hereditary condition in cases where the histology is suggestive for a familial cancer syndrome. In recent years, the knowledge regarding all of the above roles, including the role of recognition of familial cancer, has particularly expanded in renal neoplasms with the close scrutiny to morphology, molecular correlates and clinical features of the different sub-types of renal cell carcinoma. Awareness of these clinically distinctive sub-types and their associated histologic clues will prompt the pathologist for further immunohistochemical or molecular work up, to look for clinical information to support the suspected diagnosis of familial cancer, to alert managing physician/s to look for stigmata of history of familial cancer, which will permit triaging patients and their families for appropriate genetic counseling. This review provides a comprehensive review of the known sub-types of renal cell carcinoma that have a predilection to occur in the setting of hereditary disease; examples include renal cancers occurring in the background of von Hippel Lindau disease, hereditary leiomyomatosis and renal cell carcinoma syndrome, tuberous sclerosis, Birt Hogg Dube syndrome and succinate dehydrogenase deficiency. Herein we focus on diagnostic clues for renal tumors occurring in a non-pediatric setting that should prompt their correct recognition and reiterate the importance of the correct diagnosis.

Hereditary leiomyomatosis and renal cell carcinoma: Case report and review of the literature

Hereditary leiomyomatosis and renal cell cancer (HLRCC) is a rare genetic disorder in which the affected individuals tend to develop cutaneous leiomyomas, uterine leiomyomas, and renal cell cancer (RCC). Within the spectrum of this syndromic disease, RCC is the most severe manifestation, occurring at a younger age compared to the sporadic form. Pathological suspicion or diagnosis of HLRCC is critical for appropriate clinical management and genetic counseling of the affected family members. In this study, we report the case of a 27-year-old misdiagnosed carrier of HLRCC phenotype, who presented with a large solitary Type II papillary RCC.

Mitochondrial Dysfunction: A Novel Potential Driver of Epithelial-to-Mesenchymal Transition in Cancer

Epithelial-to-mesenchymal transition (EMT) allows epithelial cancer cells to assume mesenchymal features, endowing them with enhanced motility and invasiveness, thus enabling cancer dissemination and metastatic spread. The induction of EMT is orchestrated by EMT-inducing transcription factors that switch on the expression of “mesenchymal” genes and switch off the expression of “epithelial” genes. Mitochondrial dysfunction is a hallmark of cancer and has been associated with progression to a metastatic and drug-resistant phenotype. The mechanistic link between metastasis and mitochondrial dysfunction is gradually emerging. The discovery that mitochondrial dysfunction owing to deregulated mitophagy, depletion of the mitochondrial genome (mitochondrial DNA) or mutations in Krebs’ cycle enzymes, such as succinate dehydrogenase, fumarate hydratase, and isocitrate dehydrogenase, activate the EMT gene signature has provided evidence that mitochondrial dysfunction and EMT are interconnected. In this review, we provide an overview of the current knowledge on the role of different types of mitochondrial dysfunction in inducing EMT in cancer cells. We place emphasis on recent advances in the identification of signaling components in the mito-nuclear communication network initiated by dysfunctional mitochondria that promote cellular remodeling and EMT activation in cancer cells.

Hereditary leiomyomatosis and renal cell cancer syndrome: identification and clinical characterization of a novel mutation in the FH gene in a Colombian family

Hereditary Leiomyomatosis and Renal Cell Cancer Syndrome (HLRCC) is a rare disease and since the first report, it has been found in just over 200 families approximately, around the world (Smit et al. in Clin Genet 79:49-59, 2009). Patients in Colombia or in Latin America have not been described, as far as we know. HLRCC is inherited in an autosomal dominant manner, and it is caused by heterozygous germline mutations in the FH gene, which encodes the fumarate hydratase enzyme. It is characterized mainly by the appearance of cutaneous and uterine leiomyomas, and an early-onset, aggressive form of type 2- papillary renal cell carcinoma (Smit et al. in Clin Genet 79:49-59, 2009; Schmidt and Linehan in Int J Nephrol Renovasc Dis 7:253-260, 2014]. We report a Colombian family with HLRCC syndrome, with a novel mutation in FH gene (c.1349_1352delATGA) in which cutaneous leiomyomas have not been found, but other clinical manifestations such as type 2- papillary renal cell carcinoma, uterine leiomyomas and rare tumors were present. This investigation constitutes the first report of HLRCC syndrome in Colombia, and probably in Latin America.

Cascade Fumarate Hydratase mutation screening allows early detection of kidney tumour: a case report

BACKGROUND

Fumarate hydratase (FH) deficiency is a rare autosomal recessive disorder which results in a major defect in cellular metabolism. It presents in infancy with progressive encephalopathy, hypotonia, seizures and failure to thrive and is often fatal in childhood. It is caused by mutations in the FH gene (1q42.1) that result in deficiency of the citric acid cycle enzyme fumarate hydratase, resulting in accumulation of fumaric acid. Heterozygous germline mutations in the FH gene predispose to an aggressive autosomal dominant inherited early-onset kidney cancer syndrome: hereditary leiomyomatosis and renal cell cancer (HLRCC).

CASE PRESENTATION

Cascade FH mutation screening enabled the early diagnosis of a renal tumour in an asymptomatic parent of a child with fumarate hydratase deficiency, resulting in timely and possibly life-saving treatment.

CONCLUSION

While the theoretical risk of kidney cancer in parents of children with recessive fumarate hydratase deficiency is well recognized, to our knowledge this is the first report of a kidney tumour being detected in a parent by screening performed for this indication. This underscores the importance of offering lifelong kidney surveillance to such parents and other heterozygous relatives of children born with fumarate hydratase deficiency.

Fumarase-deficient Uterine Leiomyomas: An Immunohistochemical, Molecular Genetic, and Clinicopathologic Study of 86 Cases

Loss-of-function germline mutations in the fumarase (FH) gene of the Krebs cycle characterize hereditary leiomyomatosis and renal cell cancer syndrome. Fumarase (FH) deficiency can be diagnosed by the loss of immunohistochemical expression. In this study, we investigated the occurrence and clinicopathologic features of FH-deficient uterine smooth muscle tumors (SMTs). A total of 1583 uterine and 157 nonuterine SMTs were examined using a polyclonal FH antibody and automated immunohistochemistry, and 86 uterine leiomyomas with an FH loss were identified. The frequencies of FH deficiency for subcohorts of uterine SMTs were 1.6% for unselected nonatypical leiomyomas, 1.8% for cellular leiomyomas, 37.3% for atypical leiomyomas, and 0% for leiomyosarcomas. One extrauterine, retroperitoneal estrogen receptor-positive leiomyoma was also FH deficient. The patient age of FH-deficient uterine leiomyomas was 20 to 52 years (median, 38 y). Grossly, these tumors were often soft and amorphous resembling a fibrothecoma. Histologically, the FH-deficient nonatypical leiomyomas lacked cellular packeting and distinct collagenous zones and showed chain-like or palisading nuclear arrangements, prominent staghorn-shaped blood vessels, oval nuclei with no or at most mild atypia, small eosinophilic nucleoli, and a low mitotic rate (0 to 1/10 HPF). The FH-deficient atypical leiomyomas had nuclear atypia often manifesting as multinucleation, prominent eosinophilic nucleoli, and mitotic activity up to 7/10 HPF, with atypical mitoses seen in 32% of cases. However, similar histologic changes were seen in some non-FH-deficient atypical leiomyomas. Loss-of-function FH-gene mutations including 5 whole-gene deletions and 3 frameshift mutations were identified in 8 of 16 FH-deficient nonatypical leiomyomas using multiplex ligation-dependent probe amplification and Sanger sequencing, respectively. Follow-up data on patients with FH-deficient atypical uterine leiomyomas revealed 19 patients alive (median follow-up 27 y) and 5 patients dead. Deaths occurred 9 to 30 years after surgery at a median age of 72 years; causes of death could not be determined. These results indicate that FH-deficient uterine leiomyomas occur with a high frequency among atypical leiomyomas and infrequently in nonatypical leiomyomas and are often histologically distinctive. They seem to have a low biological potential and lack any significant association with leiomyosarcoma.

Metabolic reprogramming and epithelial-to-mesenchymal transition in cancer

Several lines of evidence indicate that during transformation epithelial cancer cells can acquire mesenchymal features via a process called epithelial-to-mesenchymal transition (EMT). This process endows cancer cells with increased invasive and migratory capacity, enabling tumour dissemination and metastasis. EMT is associated with a complex metabolic reprogramming, orchestrated by EMT transcription factors, which support the energy requirements of increased motility and growth in harsh environmental conditions. The discovery that mutations in metabolic genes such as FH, SDH and IDH activate EMT provided further evidence that EMT and metabolism are intertwined. In this review, we discuss the role of EMT in cancer and the underpinning metabolic reprogramming. We also put forward the hypothesis that, by altering chromatin structure and function, metabolic pathways engaged by EMT are necessary for its full activation.

Hereditary leiomyomatosis and renal cell cancer (HLRCC): cutaneous and renal manifestations requiring a multidisciplinary team approach

Cutaneous leiomyomasare rare tumours of smooth muscle origin associated with disorders such as hereditary leiomyomatosis and renal cell cancer (HLRCC) syndrome. HLRCC is an autosomal dominant syndrome caused by loss of function mutations in the fumarate hydratase gene. Sufferers of this disorder are predisposed to the development of tumours of the skin and/or uterus, with a further subset of HLRCC families at risk of renal cell carcinoma with papillary features. This syndrome is rare and carries with it a significant rate of mortality. A multidisciplinary approach to care is critical in the management of these patients and their families. The dermatologist can play a central role in this process, coordinating care between specialist medical and allied health teams.

Comprehensive genomic and phenotypic characterization of germline FH deletion in hereditary leiomyomatosis and renal cell carcinoma

Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) is a familial cancer syndrome associated with the development of cutaneous and uterine leiomyomas, and an aggressive form of type 2 papillary kidney cancer. HLRCC is characterized by germline mutation of the FH gene. This study evaluated the prevalence and clinical phenotype of FH deletions in HLRCC patients. Patients with phenotypic manifestations consistent with HLRCC who lacked detectable germline FH intragenic mutations were investigated for FH deletion. A series of 28 patients from 13 families were evaluated using a combination of a comparative genomic hybridization (CGH) array and/or CLIA-approved FH deletion/duplication analyses. Thirteen distinct germline deletions were identified in the 13 UOB families, including 11 complete FH gene deletions and 2 partial FH gene deletions. The size of eight evaluated complete FH deletions varied from ∼4.74 Mb to 249 kb, with all deletions resulting in additional gene losses. Two partial FH gene deletions were identified, with one resulting in loss of exon 1 and the upstream region of the FH gene only. Kidney cancer was diagnosed in 9 (32%) of 28 patients and 7 (54%) of 13 families possessing either complete or partial FH deletions. Cutaneous and uterine leiomyomas were observed at similar rates to those in FH point mutation families. Complete or partial FH gene alterations in HLRCC families are associated with all of the canonical HLRCC manifestations, including type 2 papillary kidney cancer and should be screened for in any patient at-risk for this disorder.

Hereditary Kidney Cancer Syndromes and Surgical Management of the Small Renal Mass

The management of patients with hereditary kidney cancers presents unique challenges to clinicians. In addition to an earlier age of onset compared with patients with sporadic kidney cancer, those with hereditary kidney cancer syndromes often present with bilateral and/or multifocal renal tumors and are at risk for multiple de novo lesions. This population of patients may also present with extrarenal manifestations, which adds an additional layer of complexity. Physicians who manage these patients should be familiar with the underlying clinical characteristics of each hereditary kidney cancer syndrome and the suggested surgical approaches and recommendations of genetic testing for at-risk individuals.

Hereditary leiomyomatosis and renal cell cancer syndrome: An update and review

Hereditary leiomyomatosis and renal cell cancer (HLRCC) syndrome is a rare genetic disorder that predisposes individuals to multiple cutaneous leiomyomas, renal cell carcinomas, and in women, uterine leiomyomas. Also known as Reed syndrome, it is caused by a germline heterozygous mutation of the fumarate hydratase tumor suppressor gene. HLRCC is associated with significant morbidity because of pain from cutaneous and uterine leiomyomas, the cutaneous pain often of unique character. Although genetic testing is currently considered the criterion standard to diagnose HLRCC, newer immunohistochemistry markers may provide rapid and cost effective alternatives to genetic testing. Because of the potentially aggressive nature of renal cell carcinomas that develop as early as in childhood, close annual cancer surveillance is desirable in individuals with HLRCC. In this review, we offer an update and an approach to the diagnosis, management, and renal cancer surveillance in HLRCC.

Clinicopathologic and Molecular Pathology of Collecting Duct Carcinoma and Related Renal Cell Carcinomas

Collecting duct carcinoma (CDC) and related tumors [ie, renal medullary carcinoma (RMC)] are rare types of highly aggressive renal cell carcinomas (RCC) with poor prognosis. Because of the rarity and diagnostic uncertainty of them, their molecular pathology and significance have not yet been fully elucidated. CDC, RMC, fumarate hydratase-deficient RCC (including hereditary leiomyomatosis and RCC-associated RCC HLRCC-RCC), and recently reported anaplastic lymphoma kinase (ALK)-rearrangement RCC have significant morphologic overlaps, but they are separately distinct entities having different molecular pathway and clinical settings. CDC is more likely to occur in middle to old age population with immunoreactivity for PAX8 and integrase interactor-1 proteins (INI-1). Various chromosomal and genomic alterations have been reported with inconsistent results. In contrast, RMC is more likely to occur in younger patients with sickle cell trait. In RMC, loss of INI-1 expression and OCT3/4 expression are distinguished compared with other RCCs. Finally, ALK-rearrangement RCC seems to have 2 different clinical settings, one with sickle cell trait (VCL-ALK fusion) and the other without (other fusions such as TPM3-ALK, EML4-ALK, and STRN-ALK fusions). Interestingly, VCL-ALK fusion was found in pediatric patients with sickle cell trait, whereas other fusions were detected in adolescent or adult without sickle cell trait. Taken together, CDC and related tumors such as RMC, fumarate hydratase-deficient RCC (including hereditary leiomyomatosis and RCC-associated RCC), and ALK-rearrangement RCC are the distinct entities and their recognition is important for the development of future personalized therapeutic options. This review updates the clinicopathologic features of these tumors with overlapping morphology and outcome.

Tubulocystic Carcinoma of the Kidney With Poorly Differentiated Foci: A Frequent Morphologic Pattern of Fumarate Hydratase-deficient Renal Cell Carcinoma

An emerging group of high-grade renal cell carcinomas (RCCs), particularly carcinomas arising in the hereditary leiomyomatosis renal cell carcinoma syndrome (HLRCC), show fumarate hydratase (FH) gene mutation and loss of function. On the basis of similar cytomorphology and clinicopathologic features between these tumors and cases described as tubulocystic carcinomas with poorly differentiated foci (TC-PD) of infiltrative adenocarcinoma, we hypothesized a relationship between these entities. First, 29 RCCs with morphology of TC-PD were identified retrospectively and assessed for FH expression and aberrant succination (2SC) by immunohistochemistry (IHC), with targeted next-generation sequencing of 409 genes-including FH-performed on a subset. The 29 TC-PD RCCs included 21 males and 8 females, aged 16 to 86 years (median, 46), with tumors measuring 3 to 21 cm (median, 9) arising in the right (n=16) and left (n=13) kidneys. Family history or stigmata of HLRCC were identifiable only retrospectively in 3 (12%). These tumors were aggressive, with 79% showing perinephric extension, nodal involvement in 41%, and metastasis in 86%. Of these, 16 (55%) demonstrated loss of FH by IHC (14/14 with positive 2SC). In contrast, 5 (17%) showed a wild-type immunoprofile of FH+/2SC-. An intriguing group of 8 (28%) showed variable FH± positivity, but with strong/diffuse 2SC+. Next-generation sequencing revealed 8 cases with FH mutations, including 5 FH-/2SC+ and 3 FH±/2SC+ cases, but none in FH+/2SC- cases. Secondly, we retrospectively reviewed the morphology of 2 well-characterized cohorts of RCCs with FH-deficiency determined by IHC or sequencing (n=23 and n=9), unselected for TC-PD pattern, identifying the TC-PD morphology in 10 (31%). We conclude that RCCs with TC-PD morphology are enriched for FH deficiency, and we recommend additional workup, including referral to genetic counseling, for prospective cases. In addition, based on these and other observations, we propose the term "FH-deficient RCC" as a provisional term for tumors with a combination of suggestive morphology and immunophenotype but where genetic confirmation is unavailable upon diagnosis. This term will serve as a provisional nomenclature that will enable triage of individual cases for genetic counseling and testing, while designating these cases for prospective studies of their relationship to HLRCC.

Fumarate is an epigenetic modifier that elicits epithelial-to-mesenchymal transition

Mutations of the tricarboxylic acid cycle enzyme fumarate hydratase cause hereditary leiomyomatosis and renal cell cancer. Fumarate hydratase-deficient renal cancers are highly aggressive and metastasize even when small, leading to a very poor clinical outcome. Fumarate, a small molecule metabolite that accumulates in fumarate hydratase-deficient cells, plays a key role in cell transformation, making it a bona fide oncometabolite. Fumarate has been shown to inhibit α-ketoglutarate-dependent dioxygenases that are involved in DNA and histone demethylation. However, the link between fumarate accumulation, epigenetic changes, and tumorigenesis is unclear. Here we show that loss of fumarate hydratase and the subsequent accumulation of fumarate in mouse and human cells elicits an epithelial-to-mesenchymal-transition (EMT), a phenotypic switch associated with cancer initiation, invasion, and metastasis. We demonstrate that fumarate inhibits Tet-mediated demethylation of a regulatory region of the antimetastatic miRNA cluster mir-200ba429, leading to the expression of EMT-related transcription factors and enhanced migratory properties. These epigenetic and phenotypic changes are recapitulated by the incubation of fumarate hydratase-proficient cells with cell-permeable fumarate. Loss of fumarate hydratase is associated with suppression of miR-200 and the EMT signature in renal cancer and is associated with poor clinical outcome. These results imply that loss of fumarate hydratase and fumarate accumulation contribute to the aggressive features of fumarate hydratase-deficient tumours.

Sarcomas Associated With Genetic Cancer Predisposition Syndromes: A Review

: Sarcomas are rare mesenchymal malignancies that demonstrate great clinical and biological heterogeneity. A variety of sarcomas develop in the context of well-defined heritable cancer predisposition syndromes, associations that are often overlooked, given the rarity and diversity of sarcomas and the equivalent relative infrequency of cancer genetic syndromes. This review describes in detail selected heritable cancer predisposition syndromes that are known to be associated with sarcomas. Beyond the molecular and clinical features that define each syndrome, disparities in clinical presentation, natural history, and treatment of syndrome-associated compared with otherwise histologically identical sporadic sarcomas will be described. The clinical approach to selected sarcoma subsets with a view to identifying possible associations with these syndromes will then be described. Although the treatment of the majority of sarcomas will not differ significantly between sporadic cases and those associated with predisposition syndromes, knowledge of features such as unique anatomic sites of affliction or excess toxicities with particular cytotoxic therapies can facilitate alterations in therapeutic strategies to maximize efficacy and minimize toxicity. In addition, recognition of cancer genetic predisposition syndrome will allow patients and their relatives to undertake appropriate genetic counseling and testing, as well as screening, surveillance, and interventional measures, as needed. Situating sarcomas within the genetic endowment of particular patients-specifically that which confers a higher risk of malignancy-will enable clinicians to better manage the patient as a whole, complementing the great efforts currently routinely undertaken to genomically characterize somatic tumor changes with a view to achieving the dream of personalized medicine.

IMPLICATIONS FOR PRACTICE

Sarcomas are uncommon malignancies that often occur sporadically but can also arise in the setting of a recognized heritable cancer predisposition syndrome. Identification of such associations when present can facilitate refinement and optimization of treatment strategies for the sarcoma so as to minimize toxicity and maximize efficacy. Discerning genetic predisposition can also facilitate institution of genetic counseling, as well as screening or surveillance schema for both the patient and his or her relatives, if required. Vigilance for these syndromes has the potential to significantly enhance the quality and comprehensiveness of sarcoma clinical management.

Reed's Syndrome: A Case of Multiple Cutaneous Leiomyomas Treated with Liquid Nitrogen Cryotherapy

Reed's syndrome is an autosomal dominant genetic disorder. Affected individuals are at increased risk of developing benign smooth muscle tumors in the skin and uterus. In this article, we report a case of a 52-year-old female who presented to our dermatology clinic complaining of painful skin lesions on her right arm, left forearm and trunk. The patient had a past medical history of uterine leiomyomatosis for which she underwent hysterectomy 17 years ago. The patient's family history revealed that her mother, 2 sisters and 2 maternal aunts also had uterine leiomyomas. The diagnosis of Reed's syndrome was confirmed by histopathologic examination of the patient's dermal lesion in conjunction with her surgical and family histories. Five years after the initial presentation, the patient underwent treatment with liquid nitrogen cryotherapy for the dermal leiomyomas. After the treatment, marked improvement was noticed with regard to the pain and size of the skin lesions.

Diagnosis and Management of Hereditary Renal Cell Cancer

Renal cell cancer (RCC) is the common denominator for a heterogeneous group of diseases. The subclassification of these tumours is based on histological type and molecular pathogenesis. Insight into molecular pathogenesis has led to the development of targeted systemic therapies. Genetic susceptibility is the principal cause of RCC in about 2-4% of cases. Hereditary RCC is the umbrella term for about a dozen different conditions, the most frequent of which is von Hippel-Lindau disease . Here, we describe the main hereditary RCC syndromes, consider criteria for referral of RCC patients for clinical genetic assessment and discuss management options for patients with hereditary RCC and their at-risk relatives.

Diagnosis and Management of Hereditary Sarcoma

Sarcomas are rare and heterogeneous diseases that affect a younger population than most epithelial cancers. Epidemiologic studies suggest a strong genetic component to sarcomas, and many familial cancer syndromes have been described, in which sarcomas are a feature. The best known of these are the Li-Fraumeni and retinoblastoma syndromes, study of which has been pivotal to elucidating the molecular basis for the cell response to DNA damage and the cell division. Although much has been learnt about cancer biology from the study of sarcoma families, in general clinical management of increased sarcoma risk has lagged behind other cancer predisposition syndromes. With the advent of genomic tools for genetic testing, it is likely that a substantial fraction of sarcoma patients will be identified as carriers of known risk alleles. The translation of this knowledge into effective risk management programs and cancer treatments will be essential to changes in routine clinical practice.

Genetic and Chromosomal Aberrations and Their Clinical Significance in Renal Neoplasms

The most common form of malignant renal neoplasms is renal cell carcinoma (RCC), which is classified into several different subtypes based on the histomorphological features. However, overlaps in these characteristics may present difficulties in the accurate diagnosis of these subtypes, which have different clinical outcomes. Genomic and molecular studies have revealed unique genetic aberrations in each subtype. Knowledge of these genetic changes in hereditary and sporadic renal neoplasms has given an insight into the various proteins and signalling pathways involved in tumour formation and progression. In this review, the genetic aberrations characteristic to each renal neoplasm subtype are evaluated along with the associated protein products and affected pathways. The potential applications of these genetic aberrations and proteins as diagnostic tools, prognostic markers, or therapeutic targets are also assessed.

Pediatric Papillary Renal Cell Carcinoma in a Horseshoe Kidney: A Case Report with Review of the Literature

Renal cell carcinoma is the most common malignancy of the kidney in adults. In children, however, it only accounts for an estimated 1.8 to 6.3% of all pediatric malignant renal tumors. Papillary renal cell carcinoma is the second most common type of renal cell carcinoma in children. We present the case of a 12-year-old boy with a 2-month history of abdominal pain, unexplained weight loss, and gross hematuria. Computed tomography revealed a horseshoe kidney and a well-defined mass of 4 cm arising from the lower pole of the right kidney. Microscopically the tumor was composed of papillae covered with cells with abundant eosinophilic cytoplasm and high-grade nuclei with prominent nucleoli. Immunohistochemistry was performed; EMA, Vimentin, and AMACR were strongly positive while CK7, CD10, RCC antigen, TFE3, HMB-45, and WT-1 were negative. Currently, 10 months after the surgical procedure, the patient remains clinically and radiologically disease-free.