Risk factors, classification, and staging of renal cell cancer

Quantitative and qualitative evaluation of toxic metals and trace elements in the tissues of renal cell carcinoma compared with the adjacent non-cancerous and control kidney tissues

Toxic metals and trace elements (TMTE) are linked to the development of several human cancers. Many reports have documented the association between some TMTE and renal cell carcinoma. In this work, we assessed the presence (qualitative) and evaluated the concentration (quantitative) of 22 TMTE in three groups of kidney tissue samples: renal cell carcinoma (RCC), adjacent non-cancerous, and control kidney tissues from cadavers. A total of 75 paired specimens of RCC and adjacent non-cancerous tissues were harvested immediately after radical nephrectomy and preserved in 10% diluted formalin solution. Twelve specimens, age- and sex-matched from the normal kidney tissue of the cadavers, who died from non-cancerous reasons, were collected and served as control. All tissue specimens were subjected to evaluation of TMTE concentration (22 elements in each specimen) by using the inductively coupled plasma optical emission spectrometry (ICP-OES) technique. The tumor, histopathology, stage, and grade were correlated with the concentration and types of TMTE. The results showed that the histological types of RCC were as follows: clear cell type in 35 (21.5%), chromophobe 22 (13.5%), papillary 7 (4.5%), oncocytoma 5 (3.1%), and unclassified 6 (3.7%). ICP-OES revealed that tumorous (RCC) tissues had a higher concentration of 9 TMTE (Ca, Cd, K, Mg, Mn, Na, Pb, S, and Sr) compared with both the adjacent non-cancerous and control tissue. The adjacent non-cancerous kidney tissues showed the highest concentration of Fe, K, and Na. The control of kidney tissues from cadavers had the highest level of Cu, Zn, Mo, and B compared with the cancerous and adjacent non-cancerous tissues. Female patients had higher concentrations of Zn and Cu in the non-cancerous tissues of their kidneys. Younger patients had a higher concentration of B in the adjacent non-cancerous, and higher Cu in the cancerous tissues. Cadmium concentration was highest in the chromophobe cell type of RCC compared with other subtypes. There was no correlation between the TMTE concentration and the pathological stage of RCC.

Cutting Edge: Elevated Leptin during Diet-Induced Obesity Reduces the Efficacy of Tumor Immunotherapy

Various malignancies are reproducibly cured in mouse models, but most cancer immunotherapies show objective responses in a fraction of treated patients. One reason for this disconnect may be the use of young, lean mice lacking immune-altering comorbidities present in cancer patients. Although many cancer patients are overweight or obese, the effect of obesity on antitumor immunity is understudied in preclinical tumor models. We examined the effect of obesity on two immunotherapeutic models: systemic anti-CTLA-4 mAb and intratumoral delivery of a TRAIL-encoding adenovirus plus CpG. Both therapies were effective in lean mice, but neither provided a survival benefit to diet-induced obese BALB/c mice. Interestingly, tumor-bearing leptin-deficient (ob/ob) obese BALB/c mice did respond to treatment. Moreover, reducing systemic leptin with soluble leptin receptor:Fc restored the antitumor response in diet-induced obese mice. These data demonstrate the potential of targeting leptin to improve tumor immunotherapy when immune-modulating comorbidities are present.

Exploiting natural anti-tumor immunity for metastatic renal cell carcinoma

Clinical observations of spontaneous disease regression in some renal cell carcinoma (RCC) patients implicate a role for tumor immunity in controlling this disease. Puzzling, however, are findings that high levels of tumor infiltrating lymphocytes (TIL) are common to RCC. Despite expression of activation markers by TILs, functional impairment of innate and adaptive immune cells has been consistently demonstrated contributing to the failure of the immune system to control RCC. Immunotherapy can overcome the immunosuppressive effects of the tumor and provide an opportunity for long-term disease free survival. Unfortunately, complete response rates remain sub-optimal indicating the effectiveness of immunotherapy remains limited by tumor-specific factors and/or cell types that inhibit antitumor immune responses. Here we discuss immunotherapies and the function of multiple immune system components to achieve an effective response. Understanding these complex interactions is essential to rationally develop novel therapies capable of renewing the immune system's ability to respond to these tumors.

CpG-mediated modulation of MDSC contributes to the efficacy of Ad5-TRAIL therapy against renal cell carcinoma

Tumor progression occurs through the modulation of a number of physiological parameters, including the development of immunosuppressive mechanisms to prevent immune detection and response. Among these immune evasion mechanisms, the mobilization of myeloid-derived suppressor cells (MDSC) is a major contributor to the suppression of antitumor T-cell immunity. Patients with renal cell carcinoma (RCC) show increased MDSC, and methods are being explored clinically to reduce the prevalence of MDSC and/or inhibit their function. In the present study, we investigated the relationship between MDSC and the therapeutic potential of a TRAIL-encoding recombinant adenovirus (Ad5-TRAIL) in combination with CpG-containing oligodeoxynucleotides (Ad5-TRAIL/CpG) in an orthotopic mouse model of RCC. This immunotherapy effectively clears renal (Renca) tumors and enhances survival, despite the presence of a high frequency of MDSC in the spleens and primary tumor-bearing kidneys at the time of treatment. Subsequent analyses revealed that the CpG component of the immunotherapy was responsible for decreasing the frequency of MDSC in Renca-bearing mice; further, treatment with CpG modulated the phenotype and function of MDSC that remained after immunotherapy and correlated with an increased T-cell response. Interestingly, the CpG-dependent alterations in MDSC frequency and function did not occur in tumor-bearing mice complicated with diet-induced obesity. Collectively, these data suggest that in addition to its adjuvant properties, CpG also enhances antitumor responses by altering the number and function of MDSC.

Sperm-associated antigen 4, a novel hypoxia-inducible factor 1 target, regulates cytokinesis, and its expression correlates with the prognosis of renal cell carcinoma

Hypoxia plays a crucial role in many pathophysiological conditions, including cancer biology, and hypoxia-inducible factor (HIF) regulates transcriptional responses under hypoxia. To elucidate the cellular responses to hypoxia, we performed chromatin immunoprecipitation with deep sequencing in combination with microarray analysis and identified HIF-1 targets. We focused on one of the novel targets, sperm-associated antigen 4 (SPAG4), whose function was unknown. SPAG4, an HIF-1-specific target, is up-regulated in various cultured cells under hypoxia. Examination of SPAG4 expression using a tissue microarray consisting of 190 human renal cell carcinoma (RCC) samples revealed that SPAG4 is an independent prognostic factor of cancer-specific mortality. Live-cell imaging revealed localization of SPAG4 at the intercellular bridge in telophase. We also studied cells in which SPAG4 was knocked down. Hypoxia enhances tetraploidy, which disturbs cell proliferation, and knockdown of SPAG4 increased tetraploid formation and decreased cell proliferation under both normoxic and hypoxic conditions. Studies using deletion mutants of SPAG4 also suggested the involvement of SPAG4 in cytokinesis. Microarray analysis confirmed dysregulation of cytokinesis-related genes by knockdown of SPAG4. In conclusion, SPAG4 is an independent prognostic factor in RCC and plays a crucial role in cytokinesis to defend against hypoxia-induced tetraploid formation. This defensive mechanism may promote survival of cancer cells under hypoxic conditions, thus leading to poor prognosis.

Kidney Cancer and Diabetes Mellitus: A Population-Based Case-Control Study in Taiwan

Introduction: The purpose of this study was to explore whether diabetes mellitus (DM) correlates with the risk of kidney cancer in Taiwan. Materials and Methods: We designed a population-based case-control study from the Taiwan National Health Insurance Database, which consisted of 116 patients with newly diagnosed kidney cancer as cases and 464 subjects without kidney cancer as controls in 2000 to 2009. Both cases and controls were aged ≥20 years. Baseline comorbidities were compared between kidney cancer cases and controls. Results: Multivariable analysis showed no association was detected between DM and kidney cancer (OR 1.06, 95% CI, 0.58 to 1.94). Hypertension (OR 2.05, 95% CI, 1.23 to 3.42), chronic kidney diseases (OR 2.57, 95% CI, 1.23 to 5.37), cystic kidney diseases (OR 18.6, 95% CI, 1.84 to 187.6) and kidney stones (OR 4.02, 95% CI, 2.43 to 6.66) were significant comorbidities associated with increased risk of kidney cancer. Use of alpha-glucosidase inhibitor was associated with increased risk of kidney cancer (OR 4.31, 95% CI, 1.07 to 17.3). Conclusion: DM does not correlate with the risk of kidney cancer. Hypertension, chronic kidney diseases, cystic kidney diseases, kidney stones and use of alpha-glucosidase inhibitors are associated with kidney cancer. Key words: Chronic kidney disease, Cystic kidney disease, Diabetes mellitus, Hypertension, Kidney cancer, Kidney stone

Renal tumors and second primary pancreatic tumors: a relationship with clinical impact?

Background

The occurrence of synchronous or metachronous renal cell carcinoma and pancreatic tumors has been described only in a few cases in the scientific literature. The study of double primary cancers is important because it might provide understanding of a shared genetic basis of different solid tumors and to detect patients at risk for secondary malignancy.

Methods

In a combined analysis of patient registries from University Departments of Urology and Visceral Surgery, 1178 patients with pancreatic tumors and 518 patients with renal cell carcinoma treated between 2001 and 2008 were evaluated,

Results

Overall 16 patients with renal cancer and synchronous (n = 6) or metachronous (n = 10) primary pancreatic tumors were detected. The median survival of all patients was 12.6 months, for the patients with synchronous resections 25.7 months and for the patients with metachronous resections 12.2 months, respectively.

Conclusions

The association between these two etiologies of malignancy demands more detailed epidemiological and molecular investigation. Clinical outcomes would support a resection as a recommended clinically valid option.

Basic research in kidney cancer

CONTEXT

Advances in basic research will enhance prognosis, diagnosis, and treatment of renal cancer patients.

OBJECTIVE

To discuss advances in our understanding of the molecular basis of renal cancer, targeted therapies, renal cancer and immunity, and genetic factors and renal cell carcinoma (RCC).

EVIDENCE ACQUISITION

Data on recently published (2005-2011) basic science papers were reviewed.

EVIDENCE SYNTHESIS

Advances in basic research have shown that renal cancers can be subdivided based on specific genetic profiles. Now that this molecular basis has been established, it is becoming clear that additional events play a major role in the development of renal cancer. For example, aberrant chromatin remodelling appears to be a main driving force behind tumour progression in clear cell RCC. A large number of potential biomarkers have emerged using various high-throughput platforms, but adequate biomarkers for RCC are still lacking. To bring the potential biomarkers and biomarker profiles to the clinical arena is a major challenge for the field. The introduction of tyrosine kinase inhibitors (TKIs) for therapy has shifted the interest away from immunologic approaches. Nevertheless, a wealth of evidence supports immunotherapy for RCC. Interestingly, studies are now appearing that suggest a combination of TKI and immunotherapy may be beneficial. Thus far, little attention has been paid to patient-specific differences. With high-throughput methods becoming cheaper and with the advances in sequencing possibilities, this situation is expected to change rapidly.

CONCLUSIONS

Great strides have been made in the understanding of molecular mechanisms of RCC. This has led this field to the enviable position of having a range of molecularly targeted therapies. Large sequencing efforts are now revealing more and more genes responsible for tumour development and progression, offering new targets for therapy. It is foreseen that through integration of high-throughput platforms, personalised cancer treatment for RCC patients will become possible.

The association between renal cell carcinoma and multiple myeloma: insights from population-based data

OBJECTIVE

• To evaluate the hypothesis of an association between renal cell carcinoma and multiple myeloma.

PATIENTS AND METHODS

• Data from nine population-based registries in the Surveillance, Epidemiology and End Results programme were used to evaluate two separate cohorts of patients diagnosed between 1973 and 2006: patients diagnosed with renal cell carcinoma as a primary malignancy (n= 57,190) and patients diagnosed with multiple myeloma as a primary malignancy (n= 34,156). • We estimated standardized incidence ratios (SIRs) with corresponding 95% confidence intervals (CIs) by dividing the number of observed cases of multiple myeloma within the renal cell carcinoma cohort and the number of renal cell carcinoma cases within the multiple myeloma cohort by the number of expected cases for each malignancy in the US general population.

RESULTS

• The renal cell carcinoma cohort yielded 88 multiple myeloma cases during 293,511 person-years of follow up. Patients with renal cell carcinoma had a higher relative risk of multiple myeloma than the general population (SIR = 1.51, 95% CI 1.21-1.85). • The multiple myeloma cohort yielded 69 renal cell carcinoma cases during 100,804 person-years of follow up. Patients with multiple myeloma had a higher relative risk of renal cell carcinoma than the general population (SIR = 1.89, 95% CI 1.47-2.40).

CONCLUSION

• Our analyses revealed a bidirectional association between renal cell carcinoma and multiple myeloma, which typically indicates shared risk factors.

Treating the individual: The need for a patient-focused approach to the management of renal cell carcinoma

Five targeted agents have shown efficacy in advanced renal cell carcinoma. These agents were evaluated in pivotal phase III clinical trials using different treatment settings and different patient populations. As patients encountered in 'real life' clinical practice are frequently under-represented in phase III trials, making treatment decisions based on phase III data alone may have limitations. In order to support treatment decisions for patients who do not fit within the inclusion criteria of many phase III trials, physicians must consider additional data sources such as expanded access programmes, sub- and retrospective analyses, and also clinical experience. The suitability of a specific targeted agent for a given patient group, e.g. elderly, will depend on a number of factors, including disease-, patient- and treatment-related characteristics. Here, we identify the need for an individualised patient-focused approach to the management of advanced renal cell carcinoma in clinical practice. In order to optimise therapy for individual patients, we present a schema providing guidance on the wide range of parameters that should be considered when making treatment decisions. We recommend the integration of this approach into everyday clinical practice.

Incidences of kidney, pelvis, ureter, and bladder cancer in a nationwide, population-based cancer registry, Denmark, 1944-2003

OBJECTIVES

To determine changes in the population-based incidence rates, degree of histologic verification, and morphologic distribution of tumors of the kidney, pelvis, and ureter and bladder in both sexes for the duration of 60 years in Denmark.

METHODS

Age-standardized incidence rates in 5-year age and calendar intervals, histologic verification and morphologic distribution were derived from reports to the Danish Cancer Registry.

RESULTS

The incidence of kidney tumors increased by 78% among men and 32% among women during the study period; the incidence of pelvis and ureter tumors increased by 1070% and 2785%, respectively, and those of bladder tumors increased by 325% and 195%, respectively. The incidence of Wilms tumor was stable; the incidence of other kidney tumors leveled out during the last 30 years of the period and those of other 2 groups during the last 20 years. The frequency of histologic verification was stable for pelvis and ureter cancers and Wilms tumor and increased for kidney and bladder tumors. Most of the kidney tumors were of epithelial origin and most others were of urothelial origin.

CONCLUSIONS

The overall incidences of all tumors increased in both sexes during the 60-year period. Some of the increase could be due to improved diagnosis. The recent decline in rates might be due to reduced exposure to risk factors.

Variation in the distribution of trace elements in renal cell carcinoma

The development of cancer is a complex, multistage process during which a normal cell undergoes genetic changes that result in phenotypic alterations and in the acquisition of the ability to invade other sites. Inductively coupled plasma optical emission spectroscopy was used to estimate the contents of Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, P, Pb, and Zn in healthy kidney and renal cell carcinoma (RCC), and significant differences were found for all elements. Along with the progression of the malignant disease, a progressive decrease of Cd and K was observed. In fact, for Cd, the concentration in stage T4 was 263.9 times lower than in stage T1, and for K, the concentration in stage T4 was 1.73 times lower than in stage T1. Progressive accumulation was detected for P, Pb, and Zn in stage T4. For P, the concentration in stage T4 was 11.1 times higher than in stage T1; for Pb, the concentration in stage T4 was 232.7 times higher than in T1; and for Zn, the concentration in T4 was 8.452 times higher than in T1. This study highlights the marked differences in the concentrations of selected trace metals in different malignant tumor stages. These findings indicate that some trace metals may play important roles in the pathogenesis of RCC.

Compassionate use of sorafenib in patients with advanced renal cell cancer

BACKGROUND

In 2005, a phase III trial demonstrated a significant increase in progression-free survival in patients with renal cell cancer (RCC) treated with sorafenib versus placebo. While awaiting the full review by the US Federal Drug Administration, we initiated a treatment protocol as a mechanism for providing sorafenib to patients with advanced RCC but who were ineligible for other sorafenib clinical trials, also known as "compassionate use." In December 2005, sorafenib became commercially available, and this protocol was closed. Herein, we report our single-institution experience with this study.

PATIENTS AND METHODS

Eligibility criteria included adults with advanced RCC with adequate organ function and performance status (PS). Treatment consisted of sorafenib 400 mg orally twice a day.

RESULTS

We enrolled 14 patients. The median age was 64 years, and PS was 2. All had metastatic RCC that had progressed after a median of 2 therapies. One patient (7%) had a partial response, and 3 (21%) had stable disease, for a clinical benefit rate of 29%. Severe toxicities included 1 patient with each of grade 4 thrombocytopenia, grade 3 warfarin-induced coagulopathy (drug-to-drug interaction), hypertension, diarrhea, anorexia, nausea, rash, and headache. Five subjects received concomitant radiation therapy without unexpected toxicities.

CONCLUSION

Sorafenib has modest activity in patients with advanced RCC who have progressed after multiple therapies.

Radiofrequency ablation of renal tumors

Radiofrequency ablation (RFA) of renal tumors is a promising technique that plays a unique and increasingly important role in urologic oncology practices. RFA is appealing as a minimally invasive therapy that may be performed on an outpatient basis. It enables treatment of an area 3 to 5 cm in diameter, with relatively low morbidity and mortality rates. Most interventional radiologists (IRs) are familiar with RFA of liver tumors, and several principles and techniques used in the liver may be extrapolated for use in the kidney. However, it is crucial to bear in mind that local tumor ablation in the kidney presents unique challenges, secondary to the kidney's unique anatomic and physiologic features. Clinical and technical considerations, risks, and complications pertaining to RFA of renal tumors are reviewed here, including approaches commonly used in our practice.

Cigarette smoking among school-going adolescents in Kafue, Zambia

INTRODUCTION

Cigarette smoking is a leading cause of global morbidity and mortality. Interest in developing countries smoking prevalence has been growing since 1999.

OBJECTIVES

To estimate the prevalence of current cigarette smoking and associated factors among school-age adolescents in Kafue, Zambia.

METHODS

A cross sectional study was conducted using standard Global Youth Tobacco Survey (GYTS) methodology. Frequencies and odds ratios were obtained to assess the association between selected factors and current cigarette smoking.

RESULTS

Data on current smoking were available for 1872 adolescents, of whom 891 (47.6%) were males and 981 females. Overall 154 (8.2%) adolescents were current cigarette smokers, while 93 (10.4%) males and 61 (6.2%) females were current smokers (p <0.001). The majority of the smokers usually smoked at their own home or at a friend's house. Having some pocket money, having friends or parents who are smokers, and being exposed to pro-tobacco advertisements at social gatherings were associated with being a current cigarette smoker.

CONCLUSIONS

The traditional factors associated with smoking among adolescents elsewhere are also associated with smoking among adolescents in Kafue, Zambia. Public health interventions aimed to reduce adolescent smoking should be designed with these identified associations in mind.