Familial and Hereditary Renal Cancer Syndromes

von-Hippel Lindau and Hypoxia-Inducible Factor at the Center of Renal Cell Carcinoma Biology

The most common form of kidney cancer is clear cell renal cell carcinoma (ccRCC). Biallelic VHL tumor suppressor gene inactivation is the usual initiating event in both hereditary (VHL Disease) and sporadic ccRCCs. The VHL protein, pVHL, earmarks the alpha subunits of the HIF transcription factor for destruction in an oxygen-dependent manner. Deregulation of HIF2 drives ccRCC pathogenesis. Drugs inhibiting the HIF2-responsive growth factor VEGF are now mainstays of ccRCC treatment. A first-in-class allosteric HIF2 inhibitor was recently approved for treating VHL Disease-associated neoplasms and appears active against sporadic ccRCC in early clinical trials.

Contemporary treatment of metastatic renal cell carcinoma

Renal cell carcinoma is the 14th most common cancer worldwide. It is a heterogeneous group of histopathological entities, of which the most common is clear cell renal cell carcinoma. Approximately 20-30% of patients present initially with metastatic disease and an additional 20% will progress after radical surgical treatment. Metastatic disease that is non-feasible for surgical treatment remains incurable. Numerous studies have demonstrated that-with the introduction of new drugs-the treatment outcomes of metastatic disease have improved. The development of new therapies as well as the optimization and individualization of procedures allow us to hope for further progress in this area.

Deterioration in the renal function and risk of microalbuminuria after radical, simple and donor nephrectomy: A long-term outcome

Objectives:

Evaluation of deterioration in renal function and risk of micro albuminuria after radical, simple and donor nephrectomy.

Materials and Methods:

A total of 594 patients underwent nephrectomy (159 radical, 318 simple and 117 donors) from February 2009 to December 2012 in our institute. First 300 eligible patients were divided in 3 groups, each having equalled number of patients. Group 1 was consisted of patients who underwent radical, group 2 had simple and group 3 had donor nephrectomy. These patients were followed up to February 2015. Follow up of all the patients were done at first month following the surgery and then in every six months subsequently. The follow up included the measurement of serum creatinine and urinary micro albumin in a spot urine sample. CKD-EPI equation was used for calculation of e GFR.

Results:

At the end of our study, 35 patients (41.6%) in group 1 and 8 patients (8.69%) in group 2 developed CKD stage 3. During the follow-up period, 41% patients in group 1, 13% in group 2 and 4% in group 3 developed MA.

Conclusion:

Nephron-sparing surgery should be the standard treatment of renal tumors, wherever possible. There should be a regular follow up of the patients after radical, simple and donor nephrectomy because of risk of CKD. Early consultation with nephrologists should be done by the patients who are suffering from MA after nephrectomy.

Outcome of genetic evaluation of patients with kidney cancer referred for suspected hereditary cancer syndromes

OBJECTIVE

To analyze patients with kidney cancer referred for evaluation at a high-volume genetics service at a comprehensive cancer center and identify factors associated with positive tests for hereditary cancer syndromes.

METHODS

A retrospective review of patients referred to the Clinical Genetics Service at Memorial Sloan-Kettering Cancer Center was performed, and patients with a personal history of kidney cancer were identified. Patient and disease characteristics were reviewed. In all, 4 variables including age at diagnosis of kidney tumor, presence of syndromic manifestations, family history of kidney cancer, and number of primary malignancies were evaluated for association with positive test results in 2 groups: patients tested for renal cell carcinoma syndromes and Lynch syndrome. Guidance for genetic testing strategy in patients with kidney cancer is provided.

RESULTS

Between 1999 and 2012, 120 patients with a history of kidney cancer were evaluated by the Clinical Genetics Service. The mean age at kidney cancer diagnosis was 52 years (interquartile range: 42-63), with 57% being women. A family history of kidney cancer was reported by 39 patients (33%). Time between diagnosis of first cancer and genetic consultation was <1 year in 54%, 2 to 5 years in 23%, and>5 years in the remaining 23%. Overall, 95 patients were tested for genetic abnormalities with 27 (28%) testing positive. Testing for renal cell carcinoma (RCC)-related syndromes was performed on 43 patients, with 13 testing positive (30%). Lynch syndrome testing was positive in 9 patients (32%) after 28 were tested. In RCC-associated syndromes, young age of diagnosis was associated with positive test results. Conversely, syndromic manifestations and increasing number of primary malignancies were associated with positive Lynch testing.

CONCLUSIONS

The discovery of inherited kidney cancer syndromes has provided a unique opportunity to identify patients at increased risk for cancer. Factors associated with positive genetic testing are unique to different syndromes. These data suggest that in kidney cancer patients evaluated for hereditary cancer syndromes, young age is associated with diagnosis of RCC syndromes, whereas syndromic manifestations and multiple primaries are found in Lynch syndrome. These results, along with clinical awareness, may be useful for practicing urologists to select patients with kidney cancer to refer for genetic counseling.

Knowledge of genetic testing for hereditary kidney cancer in Canada is lacking: The results of the Canadian national hereditary kidney cancer needs assessment survey

INTRODUCTON

Treatment of hereditary renal cell carcinoma (HRCC) requires a multidisciplinary approach that may involve medical oncologists, geneticists, genetic counsellors, and urologists. The objective of our survey was to obtain current and representative information about the use and perceived importance of genetic testing for HRCC in Canada.

METHODS

A self-administered web-based survey was provided to Canadian medical oncologists, geneticists, genetic counsellors, and urologists in collaboration with their respective associations. The survey was created through an iterative process in consultation with the Kidney Cancer Research Network of Canada and contained both quantitative and qualitative components. The survey was designed to be exploratory and results were compared across regions.

RESULTS

The overall response was low (6.6%). Of the respondents, 42%, 33%, 19%, 5% were genetic counsellors, urologists, medical oncologists and medical geneticists, respectively. Of the respondents, 62.7% described their practice as academic, and 37.3% described it as non-academic. Non-academic respondents tended to refer for genetic counselling less frequently than academic (48.6% vs. 67.2%). Most respondents believed that genetic testing for HRCC was available (82.8%), although 47.7% did not know which tests were available. This observation was consistent across provinces. Testing for Von Hippel-Lindau syndrome was given the highest priority among respondents. Limited provider knowledge, clinical guidelines, institutional funding, access, and poor coordination between disciplines were cited as barriers to testing.

INTERPRETATION

There is a need to increase provider knowledge of genetic testing for HRCC. These findings support the development of practice guidelines and national strategies to improve coordination of specialists and access to genetics services. Limitations of the present study include low survey response which did not allow for inferential analysis by geographic region or respondent specialty.

SEOM clinical guidelines for the treatment of renal cell carcinoma

The purpose of this article was to provide updated recommendations for the diagnosis and treatment of renal cell carcinoma. Pathological confirmation is mandatory before treatment with ablative or focal therapies before any type of systemic therapy. Renal cell cancer should be staged according to the TNM classification system. A laparoscopic nephron-sparing surgery should be the approach for tumors <4 cm if technically feasible. Otherwise, radical (or partial in selected cases) nephrectomy is the treatment of choice, with lymph node dissection only performed in patients with clinically detected lymph node involvement. Some retrospective evidence for a cytoreductive nephrectomy in the postimmunotherapy era suggests a benefit in patients with good or intermediate risk or for patients with a symptomatic primary lesion. Adjuvant treatment with chemotherapy or with targeted agents is not recommended and studies are ongoing today. Patients with metastatic disease should be staged by computed tomography scans of the chest, abdomen and pelvis. The efficacy of sunitinib, bevacizumab plus interferon-α, and pazopanib is well established in patients with good and intermediate risk as well for temsirolimus in poor-risk patients. These four agents are considered standard of care in first-line treatment. Sorafenib, axitinib and everolimus are standard of care in second line in different settings based on their benefit in PFS. Besides some benefit described for IL-2 in highly selected patients in first line, there is a promising and emerging role for the new immunotherapeutic approaches in metastatic renal cell carcinoma.

The epidemiology and risk factors for renal cancer

BACKGROUND

Renal cancer is a frequently occurring malignancy with over 270,000 new cases diagnosed and it being responsible for 110,000 deaths annually on a global basis. Incidence rates have gradually increased whilst mortality rates are starting to plateau.

OBJECTIVE

To review epidemiology and risk factors for renal cancer.

METHODS

The current data is based on a thorough review of available original and review articles on epidemiology and risk factors for renal cancer with a systemic literature search utilising Medline.

RESULTS

The prevalence of associated risk factors such as genetic susceptibility, smoking, hypertension and obesity are changing and could account for the changes in incidence whilst the role of diet and occupational exposure to carcinogens requires further investigation.

CONCLUSION

Despite the evidence of various associated risk factors, further work is required from well designed studies to gain a greater understanding of the etiology of renal cancer.

Downregulation of fumarate hydratase is related to tumorigenesis in sporadic renal cell cancer

OBJECTIVE

Although germline mutations of fumarate hydratase (FH) are a useful molecular marker of hereditary leiomyomatosis and renal cell cancer (RCC) syndrome, their clinical significance in sporadic RCC has not been studied in detail. The aim of the present study was to investigate possible correlations between the expression of FH and the clinical implications of sporadic RCC.

MATERIALS AND METHODS

FH mRNA levels were evaluated in 140 tumor specimens from patients with primary RCC and in 62 specimens of corresponding normal-appearing kidney tissue using real-time quantitative polymerase chain reaction. Immunohistochemical staining was performed on 6 normal surrounding tissues and 71 RCC tissues.

RESULTS

FH mRNA levels were significantly lower in tumor tissues than in matched normal-appearing kidney tissues (p = 0.031). In all normal tissues, FH staining intensity was strong. However, the expression of FH showed no significant correlation with the pathological and clinical characteristics of patients with sporadic RCC.

CONCLUSIONS

Our results showed that FH mRNA expression decreased significantly in correlation with the transition from normal renal parenchyma to RCC. FH may be an indicator or tumorigenesis in sporadic RCC and could be a potential target for therapies against RCC in the future.

Genetic syndromes associated with renal cell carcinoma: a review

AIMS

A review of recent knowledge on heredital syndromes related to renal cell carcinoma.

METHODS

Aim of this review was to summarize the recent knowledge of genetic syndromes associated with renal cell carcinoma.

RESULTS

Summary of incidence and factors modulating risk of hereditary renal cell carcinoma development.

CONCLUSIONS

Hereditary forms of RCC are relatively rare. Their study is beneficial in many ways. In individuals at a higher risk of a hereditary syndrome, the knowledge of hereditary forms may help to significantly decrease the impact of the hereditary disease. In the general population, knowledge acquired by the study of hereditary forms of RCC may in the future contribute to both diagnosis and treatment of sporadic tumours.

Residual renal function after partial or radical nephrectomy for renal cell carcinoma

Renal cell carcinoma (RCC) is often detected incidentally and early. Currently, open partial nephrectomy and laparoscopic total nephrectomy form competing technologies. The former is invasive, but nephron-sparing; the other is considered less invasive but with more loss of renal mass. Traditionally, emphasis has been placed on oncologic outcomes. However, a patient with an excellent oncologic outcome may suffer from morbidity and mortality related to renal failure. Animal models with hypertension and diabetic renal disease indicate accelerated progression of pre-existing disease after nephrectomy. Patients with RCC are older and they have a high prevalence of diabetes and hypertension. The progression of renal failure may also be accelerated after a nephrectomy. Our analysis of the available literature indicates that renal outcomes in RCC patients after surgery are relatively poorly defined. A strategy to systematically evaluate the renal function of patients with RCC, with joint discussion between the nephrologist and the oncologic team, is strongly advocated.

The epidemiology of renal cell carcinoma

CONTEXT

Kidney cancer is among the 10 most frequently occurring cancers in Western communities. Globally, about 270 000 cases of kidney cancer are diagnosed yearly and 116 000 people die from the disease. Approximately 90% of all kidney cancers are renal cell carcinomas (RCC).

OBJECTIVE

The causes of RCC are not completely known. We have reviewed known aetiologic factors.

EVIDENCE ACQUISITION

The data provided in the current review are based on a thorough review of available original and review articles on RCC epidemiology with a systemic literature search using Medline.

EVIDENCE SYNTHESIS

Smoking, overweight and obesity, and germline mutations in specific genes are established risk factors for RCC. Hypertension and advanced kidney disease, which makes dialysis necessary, also increase RCC risk. Specific dietary habits and occupational exposure to specific carcinogens are suspected risk factors, but results in the literature are inconclusive. Alcohol consumption seems to have a protective effect for reasons yet unknown. Hardly any information is available for some factors that may have a high a priori role in the causation of RCC, such as salt consumption.

CONCLUSIONS

Large collaborative studies with uniform data collection seem to be necessary to elucidate a complete list of established risk factors of RCC. This is necessary to make successful prevention possible for a disease that is diagnosed frequently in a stage where curative treatment is not possible anymore.

Current status of partial nephrectomy for renal mass

The standard treatment for a small mass has shifted from radical nephrectomy to partial nephrectomy. The benefits of partial nephrectomy, including preserving renal function, prolonging overall survival, preventing postoperative chronic kidney disease, and reducing cardiovascular events, have been discussed in many studies. With the accumulation of surgeons' experience and simplification of the operative procedures, the warm ischemic time has become shorter despite the indication of tumor size becoming larger. With the help of intraoperative ultrasound, partial nephrectomy can be performed for an endophytic renal mass. Recently, laparoscopic partial nephrectomy has become well indicated for most renal tumors in many centers with advanced laparoscopic expertise. Open partial nephrectomy remains indicated for complex tumors. With technical innovation, robotic partial nephrectomy shows at least comparable perioperative outcomes with a benefit for challenging cases. Laparoendoscopic single-site partial nephrectomy has recently been tried in limited indications and seems to be feasible.

Germline and somatic DNA methylation and epigenetic regulation of KILLIN in renal cell carcinoma

We recently identified germline methylation of KILLIN, a novel p53-regulated tumor suppressor proximal to PTEN, in >1/3 Cowden or Cowden syndrome-like (CS/CSL) individuals who are PTEN mutation negative. Individuals with germline KILLIN methylation had increased risks of renal cell carcinoma (RCC) over those with PTEN mutations. Therefore, we tested the hypothesis that KILLIN may be a RCC susceptibility gene, silenced by germline methylation. We found germline hypermethylation by combined bisulfite restriction analysis in at least one of the four CpG-rich regions in 23/41 (56%) RCC patients compared to 0/50 controls (P < 0.0001). Of the 23, 11 (48%) demonstrated methylation in the -598 to -890 bp region in respect to the KILLIN transcription start site. Furthermore, 19 of 20 advanced RCC showed somatic hypermethylation upstream of KILLIN, with the majority hypermethylated at more than one CpG island (13/19 vs. 3/23 with germline methylation, P < 0.0001). qRT-PCR revealed that methylation significantly downregulates KILLIN expression (P = 0.05), and demethylation treatment by 5-aza-2'deoxycytidine significantly increased KILLIN expression in all RCC cell lines while only increasing PTEN expression in one line. Furthermore, targeted in vitro methylation revealed a significant decrease in KILLIN promoter activity only. These data reveal differential epigenetic regulation by DNA promoter methylation of this bidirectional promoter. In summary, we have identified KILLIN as a potential novel cancer predisposition gene for nonsyndromic clear-cell RCC, and the epigenetic mechanism of KILLIN inactivation in both the germline and somatic setting suggests the potential for treatment with demethylating agents.

Educational paper: screening in cancer predisposition syndromes: guidelines for the general pediatrician

Improvements in our understanding of the genetic basis of human disease and increased utilization of genetic testing have identified a variety of heritable disorders associated with the onset of benign or malignant neoplasms during childhood. In many cases, the optimal management of affected children is dependent upon the early detection and treatment of tumors. Surveillance strategies based on the natural history of these lesions are often complex, requiring clinical examinations and radiologic and laboratory studies that evolve over a patient's lifetime. A general pediatrician may be the first to suspect one of these disorders in a patient, or may be faced with questions regarding genetic testing, cancer risk, and cancer screening. The pediatrician may also coordinate and interpret the results of specific surveillance studies. In this review, we present the genetic etiology, presentation, natural history, and surveillance recommendations for four disparate hereditary tumor predisposing syndromes, including Beckwith-Wiedemann syndrome/idiopathic hemihyperplasia, von Hippel-Lindau disease, Li-Fraumeni syndrome, and rhabdoid tumor/schwannomatosis. These examples are meant to offer the clinician practical recommendations as well as a framework upon which to base the understanding and management of other conditions associated with an increased risk to develop tumors in childhood.

Adverse renal outcomes in subjects undergoing nephrectomy for renal tumors: a population-based analysis

BACKGROUND

There has been increasing interest in determining renal outcomes after nephrectomy for renal tumors. Previous studies have not assessed all relevant risk factors, including proteinuria.

OBJECTIVE

We sought to determine the risk and predictors for the development of adverse renal outcomes in a population-based cohort of subjects undergoing partial or complete nephrectomy.

DESIGN, SETTING, AND PARTICIPANTS

A large population-based data set was used to identify all subjects undergoing nephrectomy in Alberta, Canada, from 2002 to 2007 using administrative codes. Comorbid conditions were determined using validated algorithms, and baseline estimated glomerular filtration rate (eGFR) and proteinuria status were determined.

MEASUREMENTS

Postsurgical outcomes of end-stage renal disease, acute dialysis, chronic kidney disease (CKD) (eGFR <30 ml/min per 1.73 m(2)), and rapidly progressive CKD (eGFR <60 ml/min per 1.73 m(2) and eGFR loss ≥4 ml/min per 1.73 m(2) per year) were assessed. The risk and risk factors for developing the composite renal outcome were determined using a multivariable Cox proportional hazards model.

RESULTS AND LIMITATIONS

Of 1151 subjects, 10.5% developed an adverse renal outcome over a mean of 32 mo. Complete (vs partial) nephrectomy was associated with a hazard ratio (HR) of 1.75 (95% confidence interval [CI], 1.02-2.99) for the primary outcome, as was lower baseline eGFR. Subjects with proteinuria were more likely to experience the primary outcome (42% vs 9%), conferring an adjusted HR of 2.40 (95% CI, 1.47-3.88).

CONCLUSIONS

Clinically important adverse renal outcomes are common in patients undergoing nephrectomy for renal tumors. In addition to baseline eGFR and the extent of the renal mass removed, proteinuria is a strong independent risk factor. Assessment of proteinuria, in addition to other risk factors, should be performed to inform prognosis and the optimal treatment strategy.

Hereditary renal cancer syndromes: an update of a systematic review

CONTEXT

Hereditary renal cancers (HRCs) comprise approximately 3-5% of renal cell carcinomas (RCCs).

OBJECTIVE

Our aim was to provide an overview of the currently known HRC syndromes in adults.

EVIDENCE ACQUISITION

Data on HRC syndromes were analysed using PubMed and Online Mendelian Inheritance in Man with an emphasis on kidney cancer, clinical criteria, management, treatment, and genetic counselling and screening.

EVIDENCE SYNTHESIS

Ten HRC syndromes have been described that are inherited with an autosomal dominant trait. Eight genes have already been identified (VHL, MET, FH, FLCN, TSC1, TSC2, CDC73, and SDHB). These HRC syndromes involve one or more RCC histologic subtypes and are generally bilateral and multiple. Computed tomography and magnetic resonance imaging are the best imaging techniques for surveillance and assessment of renal lesions, but there are no established guidelines for follow-up after imaging. Except for hereditary leiomyomatosis RCC tumours, conservative treatments favour both an oncologically effective therapeutic procedure and a better preservation of renal function.

CONCLUSIONS

HRC involves multiple clinical manifestations, histologic subtypes, genetic alterations, and molecular pathways. Urologists should know about HRC syndromes in the interest of their patients and families.

Patient responses to genetic information: studies of patients with hereditary cancer syndromes identify issues for use of genetic testing in nephrology practice

Advances in the genetic basis of kidney disease may mean that genetic testing is increasingly important in reducing disease morbidity and mortality among patients. However, there is little research examining patient responses to genetic information for Mendelian and common kidney diseases. Existing research on kidney and other hereditary cancer syndromes can inform three major issues relevant to the nephrology context as follows: (1) how patients understand their risk of disease after genetic counseling and testing, (2) their emotional responses to the information, and (3) their uptake of recommended risk-reducing strategies. Prior research suggests that genetic counseling and testing may improve patient understanding of genetics, but patients still might not fully understand the meaning of their results for disease risk. Genetic counseling and testing does not appear to result in long-term negative emotional effects among patients who carry mutations or those who do not. Finally, although genetic counseling and testing may improve adherence to recommended screening strategies, adherence varies substantially across different risk-reduction options. Previous research also suggests that computer-based interventions might be a useful adjunct to genetic counseling approaches. Examining whether and how these prior findings relate to the context of hereditary kidney disease is an important area for future research.