Obesity, hypertension, and the risk of kidney cancer in men

Time trend and age-period-cohort effect on kidney cancer mortality in Europe, 1981-2000

BACKGROUND

The incorporation of diagnostic and therapeutic improvements, as well as the different smoking patterns, may have had an influence on the observed variability in renal cancer mortality across Europe. This study examined time trends in kidney cancer mortality in fourteen European countries during the last two decades of the 20th century.

METHODS

Kidney cancer deaths and population estimates for each country during the period 1981-2000 were drawn from the World Health Organization Mortality Database. Age- and period-adjusted mortality rates, as well as annual percentage changes in age-adjusted mortality rates, were calculated for each country and geographical region. Log-linear Poisson models were also fitted to study the effect of age, death period, and birth cohort on kidney cancer mortality rates within each country.

RESULTS

For men, the overall standardized kidney cancer mortality rates in the eastern, western, and northern European countries were 20, 25, and 53% higher than those for the southern European countries, respectively. However, age-adjusted mortality rates showed a significant annual decrease of -0.7% in the north of Europe, a moderate rise of 0.7% in the west, and substantial increases of 1.4% in the south and 2.0% in the east. This trend was similar among women, but with lower mortality rates. Age-period-cohort models showed three different birth-cohort patterns for both men and women: a decrease in mortality trend for those generations born after 1920 in the Nordic countries, a similar but lagged decline for cohorts born after 1930 in western and southern European countries, and a continuous increase throughout all birth cohorts in eastern Europe. Similar but more heterogeneous regional patterns were observed for period effects.

CONCLUSION

Kidney cancer mortality trends in Europe showed a clear north-south pattern, with high rates on a downward trend in the north, intermediate rates on a more marked rising trend in the east than in the west, and low rates on an upward trend in the south. The downward pattern observed for cohorts born after 1920-1930 in northern, western, and southern regions suggests more favourable trends in coming years, in contrast to the eastern countries where birth-cohort pattern remains upward.

Hypertension, antihypertensives and mutations in the Von Hippel-Lindau gene in renal cell carcinoma: results from the Netherlands Cohort Study

OBJECTIVES

Hypertension and/or antihypertensive medication are reported to be risk factors of renal cell carcinoma (RCC). We investigated whether these risk factors are associated with von Hippel-Lindau gene (VHL) mutations in RCC.

METHODS

The Netherlands Cohort Study on Diet and Cancer (NLCS) started in 1986 (n = 120 852 men and women) and uses the case-cohort methodology. After 11.3 years of follow-up, 337 RCC cases and 4774 subcohort members were available for analysis. DNA was isolated from paraffin-embedded tumour tissue for VHL analysis.

RESULTS

Cohort members who reported hypertension or use of antihypertensive medication had a slightly (non-significant) increased risk of RCC: rate ratios (RR) 1.22 [95% confidence interval (CI), 0.94-1.58] and 1.14 (95% CI, 0.85-1.52), respectively. RRs were adjusted for sex, age, body mass index (BMI) and cigarette smoking. Of the 235 patients for whom tumour tissue specimens were collected, 187 had a clear-cell RCC, of whom 114 had a VHL mutation. History of hypertension was associated with a non-significantly increased risk of clear-cell RCC with VHL mutations: RR = 1.34 (95% CI, 0.87-2.07), and was not associated with the risk of clear-cell RCC without VHL mutations; RR = 0.88 (95% CI, 0.51-1.53). Use of diuretics was associated with clear-cell RCC without VHL mutations; RR = 2.11 (95% CI, 1.16-3.83).

CONCLUSIONS

In this study non-significantly increased risks for history of hypertension and use of antihypertensive medication with RCC were observed. The association with hypertension was stronger in RCC patients with VHL mutations, while there was a positive association of diuretics use and risk of RCC without VHL mutations.

Body mass index, physical activity, and risk of renal cell carcinoma

OBJECTIVE

To investigate the association between obesity and risk of renal cell carcinoma and to examine whether the association is modified by physical activity.

SUBJECTS

A population-based case-control study of 406 patients with renal cell carcinoma and 2434 controls conducted in Iowa.

METHODS

Information was collected on weight at the ages 20-29, 40-49, and 60-69 years, height, nonoccupational physical activity, diet, and other lifestyle factors. Renal cell carcinoma risk was estimated by odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for age, total energy intake, and other confounding factors.

RESULTS

Height and total energy intake were not associated with risk in either sex. In men, neither physical activity nor level of obesity in any period of life was significantly associated with risk. In women, lower physical activity was associated with higher risk (OR=2.5; 95% CI=1.2-5.2 comparing exercise <1 time/month to >1 time/day). Compared with women in the lowest quartile for BMI, the risks of renal cell carcinoma for women in the highest 10% of BMI in their 20s, 40s, and 60s were 1.4 (CI=0.6-3.1), 1.9 (CI=0.9-4.2), and 2.3 (CI=0.9-6.0), respectively. When analyses were limited to self-respondent data, the corresponding ORs were 2.9 (CI=1.2-7.4), 3.2 (CI=1.3-7.5), and 2.1 (CI=0.7-6.4), respectively. There was little evidence that physical activity modifies the association of BMI with renal cell carcinoma.

CONCLUSION

Nonoccupational physical activity was inversely associated and obesity was positively associated with risk of renal cell carcinoma among women. The risk appeared to be greater for women in the highest 10% of BMI in their 40s. Our finding of little evidence of an interaction between physical activity and BMI requires confirmation.

Fruits and vegetables and renal cell carcinoma: Findings from the European prospective investigation into cancer and nutrition (EPIC)

We examined the association between fruits and vegetables and risk of renal cell carcinoma (RCC) in the European Prospective Investigation into Cancer and Nutrition (EPIC). Dietary intake data and complete follow-up information on cancer incidence were available for 375,851 participants recruited in EPIC centers of 8 countries. During an average follow-up of 6.2 years, 306 incident cases of RCC were identified. The associations of consumption of total vegetables, total fruits, combined total fruits and vegetables and specific subtypes of vegetables with RCC risk were analyzed using Cox proportional hazards, stratified by centre and adjusted for potential confounders. No significant associations between fruit and vegetable consumption and RCC risk were observed despite a wide range of intake. The estimated relative risks (95% confidence intervals [CI]) in men and women combined were 0.97 (0.85-1.11) per 40 g increase in vegetable intake, 1.03 (0.97-1.08) per 40 g increase in fruit intake and 1.02 (0.93-1.11) per 80 g increase in fruit and vegetable intake combined. Among the vegetable subtypes, an inverse association was observed for root vegetables (RR per 8 g increase: 0.88; 95% CI: 0.78-0.99). These results suggest that total consumption of fruits and vegetables is not related to risk of RCC, although we cannot exclude the possibility that very low consumption is related to higher risk. The relationship of specific fruit and vegetable subgroups with RCC risk warrant further investigation.

Obesity and incidence of cancer: a large cohort study of over 145,000 adults in Austria

We investigated the relation of overweight and obesity with cancer in a population-based cohort of more than 145 000 Austrian adults over an average of 9.9 years. Incident cancers (n=6241) were identified through the state cancer registry. Using Cox proportional-hazards models adjusted for smoking and occupation, increases in relative body weight in men were associated with colon cancer (hazard rate (HR) ratio 2.48; 95% confidence interval (CI): 1.15, 5.39 for body mass index (BMI) ⩾35 kg m⁻²) and pancreatic cancer (HR 2.34, 95% CI: 1.17, 4.66 for BMI>30 kg m⁻²) compared to participants with normal weight (BMI 18.5–24.9 kg m⁻²). In women, there was a weak positive association between increasing BMI and all cancers combined, and strong associations with non-Hodgkin's lymphomas (HR 2.86, 95% CI: 1.49, 5.49 for BMI⩾30 kg m⁻²) and cancers of the uterine corpus (HR 3.93, 95% CI: 2.35, 6.56 for BMI⩾35 kg m⁻²). Incidence of breast cancer was positively associated with high BMI only after age 65 years. These findings provide further evidence that overweight is associated with the incidence of several types of cancer.

Bayesian modelling of imperfect ascertainment methods in cancer studies

Tumour registry linkage, chart review and patient self-report are all commonly used ascertainment methods in cancer epidemiology. These methods are used for estimating the incidence or prevalence of different cancer types in a population, and for investigating the effects of possible risk factors for cancer. Tumour registry linkage is often treated as a gold standard, but in fact none of these methods is error free, and failure to adjust for imperfect ascertainment can lead to biased estimates. This is true both if the goal of the study is to estimate the properties of each ascertainment type, or if it is to estimate cancer incidence or prevalence from one or more of these methods. Although rarely applied in the literature to date, when cancer is ascertained by three or more methods, standard latent class models can be used to estimate cancer incidence or prevalence while adjusting for the estimated imperfect sensitivities and specificities of each ascertainment method. These models, however, do not account for variations in these properties across different cancer sites. To address this problem, we extend latent class methodology to include a hierarchical component, which accommodates different ascertainment properties across cancer sites. We apply our model to a data set of 169 lupus patients with three ascertainment methods and eight cancer types. This allows us to estimate the properties of each ascertainment method without assuming any to be a gold standard, and to calculate a standardized incidence ratio for cancer for lupus patients compared to the general population. As our data set is small, we also illustrate the effects as more data become available. We show that our model produces parameter estimates that are substantially different from the currently most popular method of ascertainment, which uses tumour registry data alone.

A Prospective Study of Body Mass Index, Hypertension, and Smoking and the Risk of Renal Cell Carcinoma (United States)

OBJECTIVE

We prospectively investigated the independent association of hypertension, thiazide use, body mass index, weight change, and smoking with the risk of renal cell carcinoma among men and women using biennial mailed questionnaires.

METHODS

The study population included 118,191 women participating in the Nurses' Health Study and 48,953 men participating in the Health Professionals Follow-up Study.

RESULTS

During 24 years of follow-up for women and 12 years for men, 155 and 110 incident cases of renal cell carcinoma were confirmed, respectively. In multivariate models including age, body mass index (BMI), smoking and hypertension, higher BMI was confirmed as a risk factor for women and smoking as a risk factor for men and women. After adjusting for age, updated BMI and smoking, an updated diagnosis of hypertension was associated with renal cell carcinoma (RCC); the relative risk (RR) was 1.9 (95% CI 1.4-2.7) for women and 1.8 (95% CI 1.2-2.7) for men. Based on limited data regarding the use of thiazide diuretics, we did not observe a risk associated with their use, independent of the diagnosis of hypertension.

CONCLUSIONS

Diagnosis of hypertension, higher BMI, and increasing pack-years of smoking appear to independently increase the risk of renal cell carcinoma.

Risk factors for kidney cancer in a Japanese population: findings from the JACC Study

BACKGROUND: The incidence of kidney cancer is high in Western and Northern Europe and North America, and low in Asia. Although the incidence of kidney cancer in Japan is lower than the rates in the other industrialized countries, there is no doubt that it is increasing.

METHODS: We evaluated the risk factors for kidney cancer death using the database of the Japan Collaborative Cohort (JACC) Study (i.e., medical history, anthropometry, and lifestyle including dietary habits). The analytic cohort included 47,997 males and 66,520 females aged 40 years and older. The Cox proportional hazards model was used to determine adjusted relative risks.

RESULTS: A total of 36 males and 12 females died from kidney cancer during the follow-up of 9.6 ± 2.6 years and 9.9 ± 2.2 years, respectively. A medical history of hypertension, a fondness for fatty food, and consumption of black tea were associated with an increased risk of kidney cancer death while an intake of taro, sweet potato and potato was associated with a decreased risk.

CONCLUSIONS: The present study showed four factors to be related to kidney cancer death. However, further studies may be needed to evaluate risk factors for kidney cancer death in Japan because the number of kidney cancer death in the present study was small.

Health ramifications of the obesity epidemic

For the first time in human history, the numbers of overweight and underweight individuals are about the same, at 2.1 billion each. Along with the current worldwide obesity epidemic is the explosion of obesity- and overweight-related health problems, including diabetes and the metabolic syndrome, musculoskeletal disorders,cardiovascular disease, pulmonary disorders, and certain forms of cancer. Obesity and overweight account for a significant percentage of overall health care costs and contribute significantly to morbidity and mortality in the United States and around the world.

Renal artery changes in patients with primary renal cell carcinoma

Arterial fibromuscular dysplasia (FMD) is a noninflammatory, nonatherosclerotic, occlusive condition of the systemic arteries, most frequently affecting renal arteries. Renal cell carcinoma (RCC) might be associated with arterial hypertension; however, there are no data in the literature regarding the relationship between RCC and associated renal artery changes. We analyzed a consecutive series of 57 (35 male and 22 female) patients aging from 35 to 79 years (mean 58.9 years) who underwent nephrectomy due to RCC in the year 2003. The patients had RCC measuring from 2 to 16 cm (mean 7.1 cm). Specimens were routinely fixed, embedded in paraffin, cut, and stained with hematoxylin and eosin, Mallory trichrome method, and orcein. Renal arteries of 26 patients (20 male, 6 female) showed no changes. In these patients, RCC measured 2.5-11 cm in largest diameter (mean 6.6 cm). In 24 patients (10 male, 14 female), renal arteries showed FMD. RCCs in these patients measured between 2 and 16 cm (mean 8.0 cm). Seven patients had atherosclerotic changes in renal arteries. In this series, FMD was found in a significant proportion of patients with RCC, mainly in women. The cause of such changes and their relationship with RCC and systemic hypertension should be further analyzed.

Body size and risk of renal cell carcinoma in the European Prospective Investigation into Cancer and Nutrition (EPIC)

Previous studies suggest that obesity is related to increased risk of renal cell carcinoma (RCC); however, only a few studies report on measures of central vs. peripheral adiposity. We examined the association between anthropometric measures, including waist and hip circumference and RCC risk among 348,550 men and women free of cancer at baseline from 8 countries of the European Prospective Investigation into Cancer and Nutrition (EPIC). During 6.0 years of follow-up we identified 287 incident cases of RCC. Relative risks were calculated using Cox regression, stratified by age and study center and adjusted for smoking status, education, alcohol consumption, physical activity, menopausal status, and hormone replacement therapy use. Among women, an increased risk of RCC was conferred by body weight (relative risk [RR] in highest vs. lowest quintile = 2.13; 95% confidence interval [CI] = 1.16-3.90; p-trend = 0.003), body mass index (BMI) (RR = 2.25; 95% CI = 1.14-4.44; p-trend = 0.009), and waist (RR = 1.67; 95% CI = 0.94-2.98; p-trend = 0.003) and hip circumference (RR = 2.30; 95% CI = 1.22-4.34; p-trend = 0.01); however, waist and hip circumference were no longer significant after controlling for body weight. Among men, hip circumference (RR = 0.44; 95% CI = 0.20-0.98; p-trend = 0.03) was related significantly to decreased RCC risk only after accounting for body weight. Height was not related significantly to RCC risk. Our findings suggest that obesity is related to increased risk of RCC irrespective of fat distribution among women, whereas low hip circumference is related to increased RCC risk among men. Our data give further credence to public health efforts aiming to reduce the prevalence of obesity to prevent RCC, in addition to other chronic diseases.

Effects of excess weight on cancer incidences depending on cancer sites and histologic findings among men: Korea National Health Insurance Corporation Study

PURPOSE

The effects of excess weight on the development of cancers are controversial, and little is known for populations outside the United States and Europe. We conducted this study to assess the effects of excess weight with a large cohort of Koreans.

METHODS

We assessed the relationship between body mass index (BMI) and various cancers in a 10-year follow-up cohort of 781,283 Korean men who were free of prior cancer at baseline. Weight and height were measured, and questionnaires related to health behaviors and medical history were completed. Data on newly developed cancers were obtained from two organizations in Korea. A proportional hazards model was used to examine the relationship between BMI and cancer.

RESULTS

Adenocarcinoma in the colon and rectosigmoid, hepatocellular carcinoma, cholangiocarcinoma, adenocarcinoma in the prostate, renal cell carcinoma, papillary carcinoma in the thyroid, small-cell carcinoma in the lung, non-Hodgkin's lymphoma, and melanoma had positive dose-dependent relationships with BMI (all P < .05). Although no linear trend was found (P = .267), obese men who never smoked with a BMI of >or= 30 kg/m(2) had an increased risk of developing gastric adenocarcinoma (relative risk = 1.73). Other cancers, such as leukemia, multiple myeloma, and gallbladder and pancreatic cancer, did not show significant associations.

CONCLUSION

These findings show that, even in Koreans, obesity clearly increases the risk of many types of cancers and the strength of the associations varies with the organ and histologic type. Because these obesity-related cancers are reported to be rapidly increasing in Korea and many other Asian countries, controlling obesity epidemics could be an effective tool for preventing these cancers in these areas.

Active and passive smoking and risk of renal cell carcinoma in Canada

This study aimed to assess the role of active and passive smoking in the development of renal cell carcinoma (RCC). Mailed questionnaires were completed by 1279 incident RCC cases and 5370 population controls between 1994 and 1997 in eight Canadian provinces. Data were collected on socio-economic status, smoking habits, diet and passive smoking status, as well as residential and occupational history. The study found an increased risk of RCC associated with active smoking. Elevated risk of RCC was also observed with passive smoking; compared with those never exposed to either passive or active smoking, men and women with 43 or more years of passive residential and/or occupational exposure had respective adjusted Odds Ratios (ORs) of 3.9 (95% Confidence Interval (CI) 1.4-10.6) and 1.8 (95% CI 1.0-3.3) (P=0.001 and P=0.09, respectively). Both active and passive smoking might play a role in the aetiology of RCC.

A cohort study of antihypertensive treatments and risk of renal cell cancer

We studied 335 682 county residents, of whom 113 298 had been prescribed antihypertensive treatment (AHT), in the period 1989–2002 in North Jutland County, Denmark to examine the relation between different AHTs and the risk of renal cell carcinoma (RCC). An internal comparison was performed among the different classes of AHT users with users of beta blockers as the reference, in order to address potential confounding and bias. The average follow-up was 10 years (range 0–13). Use of any AHT was associated with RCC (relative rate (RR)=1.6, 95% confidence interval (CI) 1.3–1.9) compared with nonusers in the general population. Specific classes of AHTs were nonsignificantly associated with RCC, but compared with users of beta blockers, the numbers observed were close to expectation. Analyses by duration of follow-up and number of prescriptions revealed no clear trends for any antihypertensive agent and after 5-years of follow-up, the RRs for all classes of AHT decreased. The elevated RRs for RCC among users of AHTs compared with the general population are unlikely to be causal, but rather reflect confounding due to failure to control for pre-existing hypertension, and protopathic bias, due to the presence of hypertension as an early sign of kidney disease.

[Uncommon etiology of gastrointestinal bleeding: duodenal metastases from renal cell carcinoma]

Because of its unpredictable behavior, renal cell carcinoma is one of the most controversial neoplasms. On the one hand, patients frequently show metastases at diagnosis because of its slight manifestations, while on the other, the neoplasm can remain stable after nephrectomy and can then metastasize many years later. When this happens, the metastases usually involve more than 2 organs. The most frequent sites of metastases are the lung and lymph nodes, followed by the bones and liver, while duodenal involvement is rare. Indeed, intestinal metastases are found in only 2% of autopsies and of these, renal cell carcinoma metastases account for 7.1%. We present a case of a solitary late recurrence presenting as upper gastrointestinal bleeding 19 years after nephrectomy for clear cell renal carcinoma.

The utility of screening renal ultrasonography: identifying renal cell carcinoma in an elderly asymptomatic population

OBJECTIVE

To evaluate the efficacy and utility of screening renal ultrasonography (RUS) in older patients with a high prevalence of risk factors for renal cell carcinoma (RCC), as with the widespread use of advanced imaging techniques the identification of incidental RCC has increased, and although previous studies in low-risk groups reported little use for screening RUS, its utility in high-risk groups is unknown.

PATIENTS AND METHODS

From 1993 to 1997, screening RUS was completed for 6678 consecutive patients in conjunction with the Aneurysm Detection and Management study. Patient demographics, medical and social history were recorded for each patient. Screening RUS was completed by one ultrasonographer using a 3.5-MHz sector scanner. A urologist verified any abnormalities identified by RUS during consultation. Additional imaging tests were obtained selectively and intervention was recommended based on the results of the genitourinary evaluation.

RESULTS

From the screened population of 6678 patients, 817 (12.3%) renal anomalies were found, including a solid renal mass in 22 (0.32%), simple renal cysts in 627 (9.4%), hydronephrosis in 21 (0.31%), renal calculi in 121 (1.8%), or other abnormalities in 24 (0.36%). Treatment was completed for 15 renal cancers; 13 were organ-confined on pathological review. At a mean follow-up of >55 months, 12 of the 15 patients with RCC survived.

CONCLUSIONS

In this older cohort, retroperitoneal RUS was an effective tool for case-finding by detecting significant findings in an asymptomatic population. The prevalence of solid renal masses (0.32%) was higher than reported with other screening protocols. Although probably not the best method for generalized primary screening, the use of RUS may still be beneficial for 'secondary' screening in a more selected patient population.

HIGHLIGHTS FROM THE SOCIETY OF UROLOGIC ONCOLOGY 4th ANNUAL MEETING

PURPOSE

The 4th annual meeting of the Society of Urologic Oncology (SUO) was held December 5-6, 2003 in Bethesda, Maryland. The meeting was attended by urologists, medical and radiation oncologists, and researchers whose focus is genitourinary (GU) malignancies. More than 500 participants registered for the meeting.

MATERIALS AND METHODS

The agenda for the SUO meeting included more than 50 speakers and discussion panels, and addressed a broad range of topics in GU oncology. Transcripts of the proceedings and submitted slide presentations were reviewed for content following the meeting, and the highlights were summarized. These written materials can be accessed through the SUO web site at http://societyofurologiconcology.org.

RESULTS

Reviewed session topics included epidemiology of GU malignancies, biomarkers for GU malignancies, cancer genomics, bladder cancer, testis cancer, minimally invasive treatments for GU malignancies, molecular therapeutics and advanced prostate cancer. Significant advances in these fields have directly impacted clinical care and improved patient outcomes across the many disciplines associated with treatment of GU cancers.

CONCLUSIONS

The SUO meeting is unique in its multidisciplinary forum and focus on urological oncology. The 2003 meeting highlighted recent advances in epidemiology, clinical management and emerging molecular approaches in the diagnosis and treatment of urological malignancies with several state-of-the-art presentations.

Renal cell carcinoma in relation to cigarette smoking: meta-analysis of 24 studies

Renal cell carcinoma (RCC) accounts for 3% of adult deaths from cancer. The risk factors for its development are still under intense investigation. Although tobacco smoke is a risk factor, the data are inconsistent and the extent of the increased risk is unclear. Estimates from 19 case-control and 5 cohort studies were used. The case-control reports included 8,032 cases and 13,800 controls; the cohort estimates were based on 1,457,754 participants with 1,326 cases of RCC. The relative risk (RR) for RCC for ever smokers as compared to lifetime never smokers was 1.38 (95% confidence interval [CI] = 1.27-1.50). The RR for male smokers was 1.54 (95% CI = 1.42-1.68) and for female smokers was 1.22 (95% CI = 1.09-1.36). For men and women there was a strong dose-dependent increase in risk. Ever smoker men who had smoked 1-9, 10-20 or 21 or more cigarettes/day had a RR of 1.60 (95% CI = 1.21-2.12), 1.83 (95% CI = 1.30-2.57), or 2.03 (95% CI = 1.51-2.74), respectively. For women, the relative risks were 0.98 (95% CI = 0.71-1.35), 1.38 (95% CI = 0.90-2.11), or 1.58 (95% CI = 1.14-2.20), respectively. The advantages of smoking cessation were confirmed by a reduction in RR for those who had quit smoking for >10 years as compared to those who had quit for 1-10 years. Inhaled tobacco smoke is clearly implicated in the etiology of RCC, with a strong dose-dependent increase in risk associated with numbers of cigarettes smoked per day and a substantial reduction in risk for long-term former smokers.

Cancer pattern among hypertensive patients in North Karelia, Finland

The objective of this study was to determine the site-specific cancer incidence of hypertensive patients and examine the effect of blood pressure-related variables on the risk of cancers with elevated incidence among the hypertensive patients. A record linkage study of Hypertension Register of the North Karelia Project and the Finnish Cancer Registry was conducted. The mean follow-up time was 16 years. A total of 20 529 hypertensive patients were studied. Main outcome measures were standardised incidence ratios and hazard ratios. The overall cancer incidence was close to that of the general population for both men and women. The incidence rate for the kidney cancer was significantly increased in hypertensive patients (standardised incidence ratio 1.34, 95% confidence interval (CI) 1.11-1.60), as well as incidence rates for cancers of pancreas (1.26, 1.02-1.54), and endometrium (1.22, 1.01-1.44) in hypertensive women. The incidence of lung cancer was significantly decreased (0.86, 0.77-0.95). The incidence of liver cancer was elevated with borderline significance (1.36, 0.99-1.82). In Cox regression models, the use of antihypertensive drugs at baseline was a significant predictor of kidney (hazard ratio for use of antihypertensive drugs 1.89, 95% CI 0.96-3.75) and pancreatic cancer (1.78, 0.99-3.22) in women but not in men. The incidence of endometrial cancer or liver cancer was not related to blood pressure levels or the use of antihypertensive drugs. In women, obesity was a significant predictor of cancers of the endometrium, kidney and liver. In conclusion, increased occurrence of some cancer types among hypertensive patients seem to be partly explained by obesity and the use of antihypertensive drugs.

The value of risk-factor ("black-box") epidemiology

Risk-factor epidemiology has been denigrated by some as an empty search for associations, unguided by underlying theory. It has been defended for occasionally identifying useful (if poorly understood) potential interventions. We further defend risk-factor epidemiology as a valuable source of seemingly unrelated facts that await coherent explanation by novel theories and that provide empiric tests of theories. We illustrate these points with a theory that invokes lipid peroxidation as an explanation of an apparently incoherent accumulation of facts about renal-cell carcinoma. The example illustrates the value of viewing epidemiologic, laboratory, and clinical observations as a body of facts demanding explanation by proposed causal theories, whether or not those observations were collected with any hypothesis in mind.

Altered messenger RNA and protein expressions for insulin-like growth factor family members in clear cell and papillary renal cell carcinomas

BACKGROUND

The purpose of the present paper was to describe the pattern of expression of insulin-like growth factor (IGF-I) and its regulatory binding proteins (IGFBP) in renal cell carcinoma (RCC).

METHODS

The expressions of mRNA and protein for various IGF members were assessed in 24 paired normal and malignant human renal tissues (16 clear cell and 8 papillary RCC) using semiquantitative reverse transcription-polymerase chain reaction and immunohistochemistry. Paired tissue samples were also obtained from six patients with oncocytoma in order to compare the specificity of changes in IGF/IGFBP expression between tumors derived from proximal (RCC) and distal (oncocytoma) tubular epithelium.

RESULTS

Clear cell RCC were characterized by significant increases in the mRNA expression of IGF-I, IGFBP-3 and IGFBP-6 while papillary RCC exhibited down-regulated expression of IGF-I, IGFBP-4 and IGFBP-5. The IGFBP-2, IGFBP-4 and IGFBP-5 mRNA were down-regulated in oncocytomas. Semiquantitative assessment of immunohistochemical staining demonstrated significant increases in epithelial associated IGF-I and IGFBP-3 in clear cell RCC, increased IGFBP-5 protein in papillary RCC and no significant changes in IGF/IGFBP protein expression in oncocytoma.

CONCLUSIONS

The expression of IGF-I and certain IGFBP is significantly altered in RCC compared with normal renal tissue and oncocytomas. This altered expression is differentially regulated according to the histologic subtype of RCC, and suggests that the IGF/IGFBP axis may play an important role in determining the malignant phenotype of RCC.

A renal mass in the setting of a nonrenal malignancy: When is a renal tumor biopsy appropriate?

BACKGROUND

Frequently, a renal mass is identified when patients with cancer undergo studies for staging or surveillance. In determining whether it represents a metastasis, patients are frequently subjected to percutaneous renal biopsies. The authors evaluated their experience with this dilemma to formulate management guidelines.

METHODS

The authors reviewed the medical records of 100 consecutive patients with nonrenal malignancies diagnosed with renal masses at presentation or follow-up. Renal mass histology was available for all patients after nephrectomy or biopsy. Clinical characteristics were assessed to identify factors predictive for a renal metastasis versus a primary renal neoplasm.

RESULTS

The only factors predictive of a metastasis to the kidney were progression of the nonrenal malignancy and lack of enhancement of the renal mass (P < 0.0001). Forty-six patients (46%) had evidence of progression of their nonrenal malignancy in addition to the renal mass. In these patients, the probability of a metastasis to the kidney was 86% (95% confidence interval [CI], 57.2-98.2%) without renal mass enhancement and 32% (95% CI, 14-55%) with enhancing renal masses. None of the 54 patients without signs of progression of their nonrenal malignancy proved to have metastases to the kidney, regardless of the imaging characteristics of the mass (zero probability; 95% CI, 0-7%; P < 0.001).

CONCLUSIONS

In patients presenting with renal masses and another clinically localized malignancy, renal mass biopsies were not indicated, as the mass rarely represented a metastasis. These patients may opt for close surveillance or extirpation based on the prognosis of their nonrenal malignancy.

Relation of height, body mass, energy intake, and physical activity to risk of renal cell carcinoma: results from the Netherlands Cohort Study

Data from the Netherlands Cohort Study on Diet and Cancer were used to investigate the association between anthropometry, energy intake, and physical activity and risk of renal cell carcinoma (RCC). The Netherlands Cohort Study on Diet and Cancer consists of 120,852 men and women aged 55-69 years who completed a self-administered questionnaire at baseline (1986). A case-cohort approach was used. After 9.3 years of follow-up, 275 microscopically confirmed incident cases were available for analysis. Incidence rate ratios for RCC were estimated using Cox proportional hazards models. Height was associated with RCC risk only in women (per 5-cm increment, rate ratio (RR) = 1.23, 95% confidence interval (CI): 1.03, 1.46). Body mass index (weight (kg)/height (m)(2)) was associated with increased risk of RCC (per 1-kg/m(2 )increment, RR = 1.07, 95% CI: 1.02, 1.12) for men and women, as was gain in body mass index from age 20 years to baseline (per 1-kg/m(2 )increment, RR = 1.06, 95% CI: 1.01, 1.10). Energy intake was not related to RCC risk, while a possible protective effect was observed for physical activity in men. These results suggest that body mass index and gain in body mass index since age 20 are associated with increased risk of RCC.

The association between obesity and the progression of prostate and renal cell carcinoma

Obesity has been linked to the incidence and mortality of several malignancies, including prostate and renal cancer. Increased body mass appears to have a more consistent association with prostate cancer mortality than incidence and recent studies suggest that it may be related to higher recurrence rates after radical prostatectomy. Obesity has an even stronger association with the development and progression of renal cancer, particularly in women. Since obesity is one of few modifiable risk factors that may impact the clinical course of these cancers, lifestyle and dietary changes to limit obesity should be recommended.

Obesity and cancer

Large prospective studies show a significant association with obesity for several cancers, and the International Agency for Research on Cancer has classified the evidence of a causal link as 'sufficient' for cancers of the colon, female breast (postmenopausal), endometrium, kidney (renal cell), and esophagus (adenocarcinoma). These data, and the rising worldwide trend in obesity, suggest that overeating may be the largest avoidable cause of cancer in nonsmokers. Few obese people are successful in long-term weight reduction, and thus there is little direct evidence regarding the impact of weight reduction on cancer risk. If the correlation between obesity and cancer mortality is entirely causal, we estimate that overweight and obesity now account for one in seven of cancer deaths in men and one in five in women in the US.

The superior prognostic value of humoral factors compared with molecular proliferation markers in renal cell carcinoma

BACKGROUND

The American Joint Committee on Cancer and the Union Internationale Contre le Cancer have acknowledged routine laboratory parameters, such as serum calcium, alkaline phosphatase, hemoglobin, and the erythrocyte sedimentation rate (ESR), as predictors of survival in patients with renal cell carcinoma. The predictive value of these parameters compared with proliferation markers, such as Ki-67, proliferating cell nuclear antigen (PCNA), topoisomerase II-alpha, and p100, has not been determined.

METHODS

Forty-eight consecutive patients who underwent nephrectomy for nonmetastatic renal cell carcinoma between 1990 and 1994 were observed up to 120 months postoperatively. Ten of 48 patients developed tumor progression 6-69 months after surgery. Routine preoperative laboratory parameters as well as tumor-specific data were assessed. Findings were compared with tumor proliferation indices, which were obtained by immunohistochemical staining for nuclear antigens Ki-67, PCNA, topoisomerase II-alpha, and p100 in paraffin embedded tumor tissue.

RESULTS

Univariate and multivariate statistical analyses demonstrated superiority of routine laboratory values compared with tumor proliferation indices in predicting progression-free survival and disease-specific death. The best predictor after tumor size and symptomatic presentation was ESR (P < 0.0001), with ESR values > 70 mm at 2 hours indicating a significantly poorer prognosis. Only the proliferation marker Ki-67 reached univariate significance at a threshold of 7%.

CONCLUSIONS

Routine laboratory parameters, such as alkaline phosphatase, lactate dehydrogenase, thrombocyte count, and especially ESR, provided superior long-term prognostic information for patients with nonmetastatic renal cell carcinoma compared with the molecular tumor proliferation markers Ki-67, PCNA, topoisomerase II-alpha, and p100.

Population-based incidence and mortality cancer trends (1986–1997) from the network of Italian cancer registries

The objective of this study was to analyse incidence and mortality cancer trends in the Italian Network of Cancer Registries (about 8,000,000 inhabitants) during the period 1986-1997. Included were 525,645 newly diagnosed cancers and 269,902 cancer deaths (subjects > 14 years). Joinpoints (points in time where trend significantly changes from linearity) were found and estimated annual percentage changes (EAPC) used to summarize tendencies. Overall cancer incidence increased in both sexes and cancer mortality significantly decreased (since 1991 among men). Lung cancer showed significantly decreasing incidence (EAPC = -1.4%) and mortality (EAPC = -1.6%) among men and increasing trends among women. In women, breast cancer incidence significantly increased (EAPC= +1.7%) and mortality decreased since 1989 (EAPC= -2.0%). Stomach cancer incidence and mortality decreased in both sexes. Prostate incidence sharply increased since 1991 and mortality decreased. Colon cancer incidence increased and rectum mortality decreased significantly in both sexes. Significant increases in incidence were also found for kidney (up to 1991 among men), urinary bladder, skin epithelioma, melanoma, liver (up to 1993 among men), pancreas, mesothelioma, Kaposi's sarcoma (up to 1995 among men), testis, thyroid, non-Hodgkin's lymphomas and multiple myeloma. Mortality significantly decreased for cancers of the oral cavity and pharynx, oesophagus, liver (women), larynx (men), bone, cervix (since 1990), central nervous system, urinary bladder, thyroid, Hodgkin's lymphomas and leukaemias (men). Non-Hodgkin's lymphoma mortality increased in both sexes. In conclusion, most of the changes seen can be explained as the effect of changes in smoking habits and of the extension of secondary prevention activities. The Italian health care system will also have to cope with growing cancer diagnostic and therapeutic needs due to population ageing.

Risk factors for adult renal cell carcinoma

This study confirmed several independent risk and protective factors for RCC identified in the authors' previous study. Protective factors such as oral contraceptive use and moderate alcohol consumption were identified only in women. Tobacco consumption and severe obesity were the main independent risk factors. There were other modifiable risk markers, however, such as occupational exposure, thiazidic drug intake, and urinary tract infections. The associations between risk factors and RCC were weak, even for tobacco, for which the association was weaker than that for lung cancer. The identified risks involve a large proportion of the population, however, and the risk attributable to these types of exposure is high. The authors' recommendations for the prevention of RCC are therefore similar to those for the prevention of cardiovascular disease and cancer, and should be disseminated to the general population. The high-risk groups identified are too large for a specific early-screening program for RCC, but such screening might be appropriate if restricted to selected age groups.

Annual report to the nation on the status of cancer, 1975-2001, with a special feature regarding survival

BACKGROUND

The American Cancer Society (ACS), the Centers for Disease Control and Prevention (CDC), the National Cancer Institute (NCI), and the North American Association of Central Cancer Registries (NAACCR) collaborate annually to provide updated information regarding cancer occurrence and trends in the U.S. This year's report features a special section on cancer survival.

METHODS

Information concerning cancer cases was obtained from the NCI, CDC, and NAACCR and information concerning recorded cancer deaths was obtained from the CDC. The authors evaluated trends in age-adjusted cancer incidence and death rates by regression models and described and compared survival rates over time and across racial/ethnic populations.

RESULTS

Incidence rates for all cancers combined decreased from 1991 through 2001, but stabilized from 1995 through 2001 when adjusted for delay in reporting. The incidence rates for female lung cancer decreased (although not statistically significant for delay adjusted) and mortality leveled off for the first time after increasing for many decades. Colorectal cancer incidence rates also decreased. Death rates decreased for all cancers combined (1.1% per year since 1993) and for many of the top 15 cancers occurring in men and women. The 5-year relative survival rates improved for all cancers combined and for most, but not all, cancers over 2 diagnostic periods (1975-1979 and 1995-2000). However, cancer-specific survival rates were lower and the risk of dying from cancer, once diagnosed, was higher in most minority populations compared with the white population. The relative risk of death from all cancers combined in each racial and ethnic population compared with non-Hispanic white men and women ranged from 1.16 in Hispanic white men to 1.69 in American Indian/Alaska Native men, with the exception of Asian/Pacific Islander women, whose risk of 1.01 was similar to that of non-Hispanic white women.

CONCLUSIONS

The continued measurable declines for overall cancer death rates and for many of the top 15 cancers, along with improved survival rates, reflect progress in the prevention, early detection, and treatment of cancer. However, racial and ethnic disparities in survival and the risk of death from cancer, and geographic variation in stage distributions suggest that not all segments of the U.S. population have benefited equally from such advances.

Preventing cancer, cardiovascular disease, and diabetes: a common agenda for the American Cancer Society, the American Diabetes Association, and the American Heart Association

Collectively, cardiovascular disease (including stroke), cancer, and diabetes account for approximately two-thirds of all deaths in the U.S. and about US dollars 700 billion in direct and indirect economic costs each year. Current approaches to health promotion and prevention of cardiovascular disease, cancer, and diabetes do not approach the potential of the existing state of knowledge. A concerted effort to increase application of public health and clinical interventions of known efficacy to reduce prevalence of tobacco use, poor diet, and insufficient physical activity-the major risk factors for these diseases-and to increase utilization of screening tests for their early detection could substantially reduce the human and economic cost of these diseases. In this article, the American Cancer Society, American Diabetes Association, and American Heart Association review strategies for the prevention and early detection of cancer, cardiovascular disease, and diabetes, as the beginning of a new collaboration among the three organizations. The goal of this joint venture is to stimulate substantial improvements in primary prevention and early detection through collaboration between key organizations, greater public awareness about healthy lifestyles, legislative action that results in more funding for and access to primary prevention programs and research, and reconsideration of the concept of the periodic medical checkup as an effective platform for prevention, early detection, and treatment.

Preventing Cancer, Cardiovascular Disease, and Diabetes

Collectively, cardiovascular disease (including stroke), cancer, and diabetes account for approximately two thirds of all deaths in the United States and about $700 billion in direct and indirect economic costs each year. Current approaches to health promotion and prevention of cardiovascular disease, cancer, and diabetes do not approach the potential of the existing state of knowledge. A concerted effort to increase application of public health and clinical interventions of known efficacy to reduce prevalence of tobacco use, poor diet, and insufficient physical activity—the major risk factors for these diseases—and to increase utilization of screening tests for their early detection could substantially reduce the human and economic cost of these diseases. In this article, the ACS, ADA, and AHA review strategies for the prevention and early detection of cancer, cardiovascular disease, and diabetes, as the beginning of a new collaboration among the three organizations. The goal of this joint venture is to stimulate substantial improvements in primary prevention and early detection through collaboration between key organizations, greater public awareness about healthy lifestyles, legislative action that results in more funding for and access to primary prevention programs and research, and reconsideration of the concept of the periodic medical checkup as an effective platform for prevention, early detection, and treatment.

Cancer mortality in Europe, 1995-1999, and an overview of trends since 1960

Mortality data, abstracted from the World Health Organization database, are presented in tabular form for 26 cancer sites or groups of sites, plus total cancer mortality, in 36 European countries during the period 1995-1999. Trends in mortality are also given in graphic form for 23 major countries plus the European Union as a whole over the period 1960-1999. In the European Union, total cancer mortality declined by 7% for both sexes over the last 5 years considered. The fall since the late 1980s was 10% in both sexes, corresponding to the avoidance of over 90000 deaths per year, as compared to the rates of the late 1980s. For the first time, over the last few years, some leveling of mortality was reported also in the Russian Federation, the Czech Republic, Poland, Hungary and other Eastern European countries, although cancer rates in those areas remain exceedingly high. The overall favorable pattern of cancer mortality over recent years is largely driven by the decline of tobacco-related cancer mortality in men. However, important components of the trends are also the persistence of substantial falls in gastric cancer, mainly in Russia and Eastern Europe, the recent decline in intestinal cancer in both sexes and of breast cancer in women, together with the long-term falls in uterine (cervical) cancer, leukemias, Hodgkin's disease and other neoplasms amenable to advancements in diagnosis and treatment. Female lung cancer mortality has been declining in the Russian Federation, but is still rising in other areas of the continent. Thus, urgent intervention is needed to bring under control the tobacco-related lung cancer epidemic in European women before it reaches the high level observed in North America. Supplementary material for this article can be found on the International Journal of Cancer website at http://www.interscience.wiley.com/jpages/0020-7136/suppmat/index.html

Prognostic value of body mass index in patients undergoing nephrectomy for localized renal tumors

OBJECTIVES

To identify whether the body mass index (BMI) has any adverse effect on the prognosis of patients with established renal cell carcinoma, given the increasing prevalence of obesity and the rising incidence of renal cell carcinoma in the United States.

METHODS

We reviewed the records of patients who underwent nephrectomy for localized disease between 1985 and 1998 at our institution. Patients were grouped according to BMI as normal (less than 25 kg/m2), overweight (25 to 30 kg/m2), or obese (more than 30 kg/m2). Cox regression analysis was used to determine the significant predictors of metastasis and survival.

RESULTS

A total of 400 patients met the inclusion criteria. On univariate analysis, normal BMI (P = 0.018), pathologic stage (P <0.0001), Fuhrman grade (P = 0.007), maximal tumor size (P = 0.005), and time to recurrence (P <0.0001) were significant predictors of disease-specific death. On multivariate regression analysis, the time to metastasis (P <0.0001) was the best predictor of disease-specific death, followed by BMI (normal versus overweight or obese; P = 0.006) and pathologic stage (P = 0.007). Patients with a normal BMI who had pathologic Stage pT3 or greater and developed metastasis within 19 months of surgery had the worst prognosis, with a disease-specific death rate of 52.0%.

CONCLUSIONS

Our findings suggest that overweight and obese patients with renal cell carcinoma have a more favorable prognosis than patients with a normal BMI. If others confirm our finding that a high BMI confers a survival advantage to patients undergoing nephrectomy, BMI may prove to be an important prognostic factor in renal cell carcinoma.

The impact of obesity in urology

The incidence and progression of urologic diseases, as well as several urologic cancers.depend on many interrelated factors, such as obesity, diet, genetics, environment, age, and the immune system. Obesity is a risk factor for stress urinary incontinence, ED, infertility, and renal calculi. Numerous publications have demonstrated that a high dietary intake of fat increases prostate cancer risk, although the mechanisms are not clear. Although some reports may demonstrate an association between obesity and prostate cancer, it may be hard to establish because, in general, men with obesity have a high-fat diet. Obesity, recurrent urinary tract infections, increased intake of protein and fried foods, and female sex seem to increase the risk of renal cancer. Environmental toxins seem to be the major factors affecting the incidence of bladder cancers. Thus, dietary modification and other public health measures directed at reducing weight may reduce the incidence of urologic illnesses. More studies are necessary to determine the therapeutic effects of weight loss and dietary modification on the incidence and progression of urologic tumors.

Targeting of the VHL-hypoxia-inducible factor-hypoxia-induced gene pathway for renal cell carcinoma therapy

Treatment of advanced renal cancer has made little progress in the past 30 yr. Most clinical efforts have incorporated cytokine-based therapy. The presumption has been that the cytokines may trigger a host immune response against the renal cancer. Only IFN-alpha and high-dose IL-2 seemed to have positive effects on patient outcomes. IFN has prolonged the lives of patients by a few months, and high-dose IL-2 is capable of inducing very prolonged remissions (>5 yr) for a small number of patients. Nephrectomy in the presence of metastatic disease has been established as an effective procedure for select patients, providing palliation and prolonging survival. Finally, enthusiasm has focused on the use of nonmyeloablative allogeneic stem cell transplantation and donor leukocyte infusion for the induction of graft versus tumor effects. Early results are both provocative and promising. A number of agents that target the critical gene products downstream from pVHL and hypoxia-inducible factor-1, such as vascular endothelial growth factor, PDGF, EGF receptor, and TGF-alpha, have recently become available. The new agents are capable of inhibiting specific cellular targets, and the biologic characteristics of clear cell carcinoma of the kidney support their application. If the correct targets are carefully selected for inhibition in tumors in which the targets are present (clear cell histologic features and loss of VHL expression), then results should resemble those others have observed with targeted therapy, such as the use of STI-571 (Gleevec; Novartis Pharmaceuticals, East Hanover, NJ) for treatment of chronic myelogenous leukemia and gastrointestinal stromal tumors or anti-HER2/neu (Herceptin; Genentech, South San Francisco, CA) for treatment of breast cancer.

The roles of IGF-I and IGFBP-3 in the regulation of proximal tubule, and renal cell carcinoma cell proliferation

BACKGROUND

Insulin-like growth factor I (IGF-I), a potent proximal tubule cell (PTC) mitogen, has been implicated in the progression of many human cancers. Our previous work on human renal tissues has suggested that IGF-I and several of its binding proteins (IGFBP-3 and -6) are up-regulated in clear cell renal cell carcinoma (RCC).

METHODS

To further elucidate the role of IGF-I and IGFBPs in RCC growth, immunohistochemistry, thymidine incorporation, and Western analysis were performed in primary cultures of normal PTC (priPTC) and clear-cell RCC (priRCC), as well as in SN12K1 cells (a cell line derived from metastatic RCC).

RESULTS

By immunohistochemistry, IGFBP-3 and IGF-I were prominently expressed in SN12K1 cells, and weakly expressed in priPTC and priRCC. Incubation with 100 ng/mL IGF-I significantly augmented DNA synthesis by priPTC (mean +/- SD 120.7%+/- 19.7% of controls, P < 0.05), priRCC (238.7%+/- 279.9% of controls, P < 0.01), and SN12K1(120.0%+/- 22.9% of controls, P < 0.05). Neutralizing antibodies to IGF-I and IGF-I receptor significantly suppressed SN12K1 growth (81.9%+/- 13.5% of control, P < 0.01 and 87.4%+/- 16.2% of control, P < 0.05, respectively). Removal of endogenous IGFBP-3 by an anti-IGFBP-3 increased SN12K1 DNA synthesis (243.9%+/- 35.3% of control, P < 0.001), which was partially abrogated by coincubation with exogenous IGFBP-3 (135.97%+/- 5.9% of controls, P < 0.001). Using Western analysis, IGFBP-3 expression was enhanced in IGF-I-stimulated SN12K1 cells exposed to exogenous IGF-I. Coincubation with anti-IGFBP-3 further enhanced IGF-I-induced DNA synthesis.

CONCLUSION

RCC cells express IGF-I and IGFBP-3, and are responsive to exogenous IGF-I stimulation. Moreover, in SN12K1 cells (derived from metastatic RCC), autocrine IGF-I and IGFBP-3 actions, respectively, stimulated and inhibited growth. These results suggest that IGF-I and IGFBP-3 may be potential candidates for therapeutic manipulation in patients with advanced RCC.

Fruits, vegetables and risk of renal cell carcinoma: A prospective study of Swedish women

Findings of epidemiologic studies on the relationship between fruit and vegetable consumption and renal cell carcinoma (RCC) risk have been inconclusive. To study the association between fruits and vegetables and risk of RCC in a population-based prospective cohort study of Swedish women, we collected dietary information from 61,000 women age 40-76 years by a food-frequency questionnaire. During 13.4 years of follow-up 122 women developed RCC. Cox proportional hazards models were used to estimate relative risks (RR) with 95% confidence interval (CI). Women consuming 5 or more servings of fruit and vegetables daily had a relative risk of 0.59 (95% CI = 0.26-1.34) in comparison to them consuming less than once daily. When fruits and vegetables were examined separately, those who consumed more than 75 servings per month of fruits or vegetables had multivariate relative risk of 0.59 (95% CI = 0.27-1.25) and 0.60 (95% CI = 0.31-1.17) respectively, compared to those consuming 11 or less servings per month. Within the group of fruits, the strongest inverse association was observed for banana (p = 0.07 by Wald test). The risk of RCC increased monotonically with increasing intake frequencies of fruit juice (p-value for trend = 0.10). Within the group of vegetables, the strongest inverse association was observed for root vegetables (p = 0.03 by Wald test). The risk of RCC decreased with increasing consumption frequencies of white cabbage (p for trend = 0.07). Frequent consumption of salad vegetables (once or more per day) decreased the risk by 40% (RR = 0.60; 95% CI = 0.30-1.22), in comparison to no consumption. Our results suggested that high consumption of fruits and vegetables might be associated with reduced risk of RCC.

Does overweight impact on the prognosis of patients with renal cell carcinoma? A single center experience of 683 patients

BACKGROUND AND OBJECTIVES

An increased incidence of renal cell carcinoma (RCC) in obese patients has been reported by several authors. We investigated the association of body mass index (BMI) with prognosis of patients with RCC.

METHODS

From January 1994 to December 2000, 693 operations for RCC in 683 consecutive patients were performed at our institution. Patients' BMI at operation was evaluated, overall, tumor-specific and progression-free survival was investigated using the Kaplan-Meier method, for multivariate analysis the Cox regression model was used.

RESULTS

Four hundred seventeen patients were males, 266 females. Mean age was 62 years (range 16-88). BMI was available in 609 (89.2%). 371/609 (60.9%) of patients exhibited a BMI greater than 25. After a mean follow-up of 41.5 months, 86 (12.6%) patients died from metastatic RCC, and 29 (4.3%) were alive with metastatic disease. A significant advantage regarding overall (P = 0.015) and progression-free (0.017) but not tumor-specific survival (P = 0.057) was found for patients with a BMI of more than 25 compared to normal-weight patients. In multivariate analysis, BMI showed no significant association with tumor-specific survival.

CONCLUSIONS

Patients with a BMI of more than 25 had a better outcome compared to patients with normal weight in univariate analysis but not multivariate analysis.

Evaluation of dietary, medical and lifestyle risk factors for incident kidney cancer in postmenopausal women

Kidney cancer incidence rates in the United States have been increasing and are not fully accounted for by better diagnostic techniques. Risk factors in women are incompletely described. A total of 34,637 Iowan women initially free of cancer completed a mailed questionnaire in 1986. Kidney cancer incidence was identified over 15 years of follow-up (n = 124) through linkage to a statewide cancer registry. Adjusted for age and other risk factors, kidney cancer was associated positively with maximum adult weight (p for trend = 0.02) and current waist-to-hip ratio (p for trend = 0.002). Compared to nondrinkers, consumers of alcohol of 3.0 or more grams per day had a relative risk (RR) of 0.52 (95% CI = 0.29-0.92). Total vitamin C intake was associated positively with risk of kidney cancer (p for trend = 0.04), whereas total vitamin E intake was associated negatively with risk (p for trend = 0.002). The few women who used copper supplements had a 6.52-fold increase in risk of kidney cancer (95% CI = 1.95-21.8). Compared to never users, women who were former users of estrogen had an increased risk of kidney cancer (RR = 1.62; 95% CI = 1.11-2.36), but current users of estrogen were not at a higher risk. Women who were nulliparous or had more than 2 live births were also at increased risk of kidney cancer compared with women who had 1 or 2 live births. In conclusion, in these postmenopausal women, overweight, particularly central adiposity, was an important risk factor for kidney cancer. Potential risk factors that warrant further exploration were low intake of alcohol and vitamin E, higher intake of vitamin C, nulli- or multiparity and use of copper supplements.

Glutathione S-transferases M1-1 and T1-1 as risk modifiers for renal cell cancer associated with occupational exposure to chemicals

AIMS

To investigate the possible interaction between occupational risk factors and genotype for glutathione S-transferases M1 and T1 (GSTM1 and GSTT1) in renal cell cancer (RCC).

METHODS

One hundred patients with RCC and 200 outpatient controls were enrolled at Parma University Hospital. The polymorphisms of glutathione S-transferase M1-1 (GSTM1) and T1-1 (GSTT1) were investigated by PCR; occupational history was collected by a structured questionnaire.

RESULTS

Subjects with GSTM1 present genotype showed higher risks for RCC, compared to GSTM1 null subjects, if exposed to metals (OR 2.73; 95% CI 0.91 to 8.22 v 1.14; 95% CI 0.46 to 2.82) or pesticides (OR 3.46; 95% CI 1.12 to 10.74 v 1.59; 95% CI 0.48 to 5.34). The GSTT1 present genotype also enhanced the risk (about twofold) of RCC among subjects exposed to solvents and pesticides, compared with those GSTT1 null.

CONCLUSIONS

Results support the hypothesis that GSTM1 and GSTT1 polymorphisms can interact with several occupational exposures to significantly modify the risk of RCC among exposed subjects.