Obesity is negatively associated with prostate-specific antigen in U.S. men, 2001-2004

Obesity and prostate cancer screening, incidence, and mortality in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial

BACKGROUND

Though obesity, measured by body mass index (BMI), is an established risk factor for several cancer sites, there is conflicting evidence on whether obesity increases prostate cancer risk or mortality and, if it does, whether it increases risk directly or indirectly by affecting prostate cancer screening efficacy.

METHODS

We examined associations between BMI and prostate cancer screening outcomes, incidence, and mortality in men randomly assigned to the intervention arm of the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (n = 36 756) between 1993 and 2001. Participants received annual screening with the prostate-specific antigen test and digital rectal exam. Associations between baseline BMI and screening outcomes were assessed via multinomial logistic regression, and associations with prostate cancer incidence and mortality were assessed via Cox proportional hazards regression.

RESULTS

Individuals with higher BMI were less likely to screen positive via the prostate-specific antigen test and/or digital rectal exam and more likely to have an inadequate screen (all Ptrend < .01). Higher BMI was inversely associated with prostate cancer incidence (per 5 kg/m2 BMI increase: hazard ratio [HR] = 0.94, 95% confidence interval [CI] = 0.91 to 0.97), including incidence of early stage (HR = 0.94, 95% CI = 0.90 to 0.97) and advanced-stage (HR = 0.91, 95% CI = 0.82 to 1.02) disease, but positively associated with prostate cancer mortality (HR = 1.21, 95% CI = 1.06 to 1.37). The association with mortality was not modified by screening outcome (Pinteraction = .13).

CONCLUSIONS

Within this screened population, individuals with higher BMI had lower risk of prostate cancer diagnosis but higher risk of prostate cancer mortality. As higher BMI was not positively associated with advanced-stage prostate cancer risk, the increased mortality is unlikely to be due to delayed prostate cancer detection.

Association between obesity and frequency of high‑grade prostate cancer on biopsy in men: A single‑center retrospective study

The present study aimed to investigate the relationship between BMI and the prostate cancer (PCa) risk at biopsy in Italian men. Retrospective analyses of the clinical data of 2,372 consecutive men undergoing ultrasound-guided multicore (≥10) prostate biopsy transrectally between May 2010 and December 2018 were performed. BMIs were categorized, according to Western countries' classification of obesity, as follows: <18.5 kg/m² (underweight), 18.5-24.99 kg/m² (normal weight), 25-30 kg/m² (overweight) and >30 kg/m² (obese). The distribution of patients undergoing biopsy was compared with a model population from the official survey data. Patient characteristics and the relationships between characteristics were investigated using correlation analysis, ANOVA, Kruskal-Wallis and Dunn's tests. The present study estimated the influence on cancer incidence not only of BMI but also of other patient characteristics using multi-variable logistic modelling and compared, using the models, the expected outcomes for patients who differed only in BMI. From a sample of 2,372 men, the present study enrolled 1,079 men due to a lack of clinical data [such as prostate specific antigen (PSA) and BMI data] in the other patients undergoing prostate biopsy. Their distribution was significantly different from the model distribution with the probability of undergoing biopsy increasing with increasing BMI. The median age was 69.4 years. The median BMI was 26.4 kg/m², while the median PSA level was 7.60 ng/ml. In total, the biopsies detected PCa in 320 men (29.7%) and high-grade PCa (HGPCa) in 218 men (20.2%). Upon applying the aforementioned Western countries' criteria for BMI categories, there were 4 (0.4%) underweight, 318 (29.5%) of normal weight, 546 (50.6%) overweight, and 211 (19.6%) obese patients. ANOVA/Kruskal-Wallis tests revealed that overweight and obese men were younger than the normal-weight men, while there was no statistical difference in their PSA values. Furthermore, 29.3% of normal-weight men, 29.5% of overweight men and 29.9% of obese men were diagnosed with PCa, while 19.5% of normal-weight men, 20.1% of overweight men and 21.8% of obese men were affected by severe cancer. BMI was found to be positively correlated with PCa risk and negatively correlated with both age and PSA level. Age and PSA level were both positively correlated with PCa risk, while digital rectal examination (DRE) outcome was strongly indicative of PCa discovery if the test outcome was positive. Logistics models attributed a positive coefficient to BMI when evaluated against both PCa risk and HGPCa risk. In patients having a negative DRE outcome who differed only in BMI, logistic regression showed a 60% increased risk of PCa diagnosis in obese patients compared with in normal-weight patients. This risk difference increased when other characteristics were less indicative of PCa (younger age/lower PSA), while it decreased when patient characteristics were more indicative (older age/higher PSA, positive DRE). In conclusion, the present study demonstrated that, in men with higher BMIs, the risk of PCa is higher. The relative difference in risk between low and high BMI is most pronounced in younger patients having a lower PSA level and a negative DRE outcome.

A Longitudinal Study of the Relationship between Shift Work and Prostate-Specific Antigen in Healthy Male Workers

As shift work has become prevalent globally, it is important to evaluate the health effects of shift work on employees. Several studies have demonstrated a positive association between shift work and prostate cancer. Therefore, we aimed to further examine the relationship between shift work and elevated prostate-specific antigen (PSA). Our study collected data from 66,817 male participants at baseline and followed up for about 6 years. We categorized shift worker status and shift schedule types. To evaluate the risk of elevated PSA on shift workers, we estimated hazard ratios using the Cox proportional hazards regression analyses. During a median follow-up of 4.1 years, 1030 participants developed elevated PSA. The multivariable-adjusted hazard ratio (HR) of elevated PSA for shift workers compared with daytime workers was 1.37 (1.04-1.80). Among shift workers, rotating shift workers (HR = 1.47, 95% CI 1.06-2.03) showed a significantly increased risk of elevated PSA compared with daytime workers. Our longitudinal study provides evidence for an association between shift work, especially rotating shift work, and elevations of PSA.

Clinical factors affecting prostate-specific antigen levels in prostate cancer patients undergoing radical prostatectomy: a retrospective study

Background:

Since prostate-specific antigen (PSA) levels can be influenced by some routinely available clinical factors, a retrospective study was conducted to explore the influence of obesity, smoking habit, heavy drinking and chronic obstructive pulmonary disease on PSA levels in men with histologically confirmed prostate cancer.

Patients & methods:

We reviewed the medical records of 833 prostate cancer patients undergoing radical prostatectomy.

Results:

Serum PSA levels at the time of surgery were not associated with either BMI or history of chronic obstructive pulmonary disease or heavy drinking. Conversely, PSA levels were associated with smoking status.

Conclusion:

Among the clinical factors explored in this homogeneous population, only tobacco use was associated with PSA levels, which should be considered when using PSA-based screening in male smokers.

Smokers with prostate cancer tend to show higher PSA levels at the time of radical prostatectomy. As higher PSA levels are associated with a worse prognosis, smoking habit may have a prognostic value in prostate cancer. Further studies are required to explore the underlying biology of this finding.

Association between prostate-specific antigen and serum testosterone: A systematic review and meta-analysis

BACKGROUND

Serum testosterone assays are an important tool in the clinical evaluation of a number of endocrine disorders including male hypogonadism. However, serum testosterone has a limited role in real clinical use due to its inaccuracy. We aimed to assess the association between prostate-specific antigen (PSA) and testosterone as well as the effects of various types of testosterone replacement therapy (TRT) for PSA level.

METHODS

Two electronic databases were screened: PubMed (1966 through December 2018) and Cochrane Library (1993 through December 2018). The first strategy compared the overall increase in PSA following testosterone treatment compared with placebo. The second strategy analyzed the overall association between PSA and testosterone among the observational studies.

RESULTS

In the first strategy, 22 articles were included in the final analysis. In the second strategy, 18 studies were included. Testosterone replacement therapy (TRT) showed a significant change in PSA level compared to that in the placebo group (mean difference [MD]: 0.13, 95% CI: 0.01-0.25, P = .04). Compared to placebo, only intramuscular (IM) TRT shows a significant change in PSA level group (MD: 0.16, 95% CI: 0.01-0.30, P = .04), as neither the oral nor topical type showed a significant change in PSA. In the second strategy analysis, there was no overall correlation found between PSA and testosterone (z = 0.04, 95% CI: -0.04 to 0.12, P = .04; r = 0.039). However, in the subgroup of non-BPH (benign prostate hyperplasia), a significant correlation between PSA and testosterone (z = 0.07, 95% CI: 0.01-0.13, P = .009; r = 0.089) was found.

CONCLUSIONS

We found that TRT, particularly IM TRT, significantly changed the PSA level compared with the placebo group. Furthermore, there was a significant correlation between PSA and testosterone in patients with non-BPH. According to these findings, we suggest the possibility of PSA as a surrogate marker of testosterone.

Prostate-Specific Antigen Within the Reference Range, Subclinical Coronary Atherosclerosis, and Cardiovascular Mortality

RATIONALE

Although PSA (prostate-specific antigen)-a tumor marker for prostate cancer-has been reported to be associated with cardiovascular disease (CVD) risk factors, studies on the association of PSA with subclinical and clinical CVD remain limited.

OBJECTIVE

We examined the association of total serum PSA within the reference range with coronary artery calcium (CAC) score and CVD mortality.

METHODS AND RESULTS

A cross-sectional study was performed in 88 203 Korean men who underwent a health checkup exam including cardiac tomography estimation of CAC score. Logistic regression model was used to calculate odds ratios with 95% CIs for prevalent CAC. PSA levels were inversely associated with the presence of CAC. After adjusting for potential confounders, multivariable-adjusted odds ratio (95% CIs) for prevalent CAC comparing PSA quartiles 2, 3, and 4 to the first quartile were 0.96 (0.90-1.01), 0.88 (0.83-0.93), and 0.85 (0.80-0.90), respectively ( P for trend, <0.001). A cohort study was performed in 243 435 Korean men with a mean age of 39.3 years, PSA values of <4.0 ng/mL, and without known CVD or prostate disease who were followed up with for ≤14 years for CVD mortality (median, 7.3 years). CVD deaths were ascertained through linkage to national death records. Hazard ratios and 95% CIs for CVD mortality were estimated using Cox proportional hazards regression analyses. During 1 829 070.1 person-years of follow-up, 336 CVD deaths were identified. After adjustment for potential confounders, multivariable-adjusted hazard ratios (95% CIs) for CVD mortality comparing PSA quartiles 2, 3, and 4 to the lowest quartile were 0.90 (0.66-1.22), 0.79 (0.58-1.08), and 0.69 (0.51-0.93), respectively.

CONCLUSIONS

Serum total PSA levels within the reference range showed an inverse association with subclinical atherosclerosis and CVD mortality in young and middle-aged Korean men, indicating a possible role of PSA as a predictive marker for subclinical and clinical CVD.

The effect of visceral fat on the hemodilution effect of serum carcinoembryonic antigen in Korean population

OBJECTIVE

To investigate the relationship between visceral fat and the hemodilution effect of carcinoembryonic antigen in both sexes.

METHODS

A total of 15,340 females and 20,024 males who visited the health promotion center at Chung-Ang University Hospital from 2011 to 2014 were retrospectively collected. Correlation analysis and chi-square test for linear by linear association were used to determine the correlation between carcinoembryonic antigen concentration, carcinoembryonic antigen mass and visceral fat. Multivariable linear regression analysis was used to calculate the mean of carcinoembryonic antigen concentration and the mean of carcinoembryonic antigen mass, reflecting age, aspartate aminotransferase, alanine aminotransferase, creatinine, body fat percentage, body mass index, lean body mass and waist circumference as confounding variables.

RESULTS

Higher body mass index was related with lower carcinoembryonic antigen concentration in men (r = -0.019, P = 0.019), but higher carcinoembryonic antigen concentration in women (r = 0.084, P<0.001). Average of waist circumference for male is greater than that of female (P<0.01). Average of body fat percentage for male is lesser than that of female (P<0.01). Male lean body mass mean is larger than that of women (P<0.01). Increased waist circumference was significantly associated with higher carcinoembryonic antigen mass in both female and male (P<0.001 for trend). Postmenopausal women might be more likely to have increased carcinoembryonic antigen mass and carcinoembryonic antigen concentration (P<0.001 for trend).

CONCLUSIONS

This study suggests that visceral fat may increase total amount of CEA in the body. Visceral fat should be taken into account when evaluating serum CEA levels in both sexes.

No association of serum PSA with vitamin D or total oxidant-antioxidant capacity in healthy men

Background and aim: Vitamin D deficiency and oxidative stress were suggested to be related to prostate cancer risk. We aimed to investigate the association of serum PSA concentration with vitamin D and total oxidant/antioxidant levels. Materials and methods: A total of 95 healthy men were enrolled for the cross sectional study. Serum PSA, 25(OH)D, serum total oxidant status, and total antioxidant status were measured. Results: Serum PSA was significantly negatively correlated with serum total oxidant status (r= -0.309, p = .003) but there was no significant correlation between PSA and 25(OH)D (p = .383) or total antioxidant levels (p = .233). After adjustment for age BMI and smoking status with multiple regression analysis, there was no significant association between serum PSA and total oxidant status. Conclusion: We find no evidence for an association between PSA and vitamin D levels or serum total oxidant/antioxidant levels.

Association between serum prostate-specific antigen level and diabetes, obesity, hypertension, and the laboratory parameters related to glucose tolerance, hepatic function, and lipid profile: implications for modification of prostate-specific antigen threshold

BACKGROUND

Previous studies indicated inverse relationships between body mass index (BMI), diabetes and prostate-specific antigen (PSA) concentration besides an established positive relationship between age and PSA. Other causal relationships between clinical parameters including hypertension, hepatic function, tests, lipid profile and PSA were also suggested. Thus, we incorporated these parameters all together into the analysis to identify possible determinants of PSA concentration to improve the accuracy of PSA tests.

METHODS

Associations between PSA and the above-mentioned clinical parameters were examined among 14,486 men who visited our hospital for a routine health checkup, using linear regression analyses.

RESULTS

Total of 1403 (9.7%) and 784 (5.4%) men were classified as diabetes and obesity, respectively. After adjusting age, significant PSA reductions were found in diabetic men, especially for men taking antidiabetics. Such association was seen when the diabetic status was represented by hemoglobin A1c (HbA1c) and fasting blood sugar (FBS) levels. That is, PSA levels were significantly reduced in men with higher HbA1c and FBS levels. Obesity was also associated with a reduction in PSA levels. Moreover, PSA levels were significantly decreased with increased ALT levels.

CONCLUSIONS

PSA test results should be carefully interpreted especially for men with diabetes and obesity, in whom a substantial reduction in PSA concentration is likely to occur.

Hypogonadotropic Hypogonadism in Men With Diabesity

One-third of men with obesity or type 2 diabetes have subnormal free testosterone concentrations. The lower free testosterone concentrations are observed in obese men at all ages, including adolescents at completion of puberty. The gonadotropin concentrations in these males are inappropriately normal; thus, these patients have hypogonadotropic hypogonadism (HH). The causative mechanism of diabesity-induced HH is yet to be defined but is likely multifactorial. Decreased insulin and leptin signaling in the central nervous system are probably significant contributors. Contrary to popular belief, estrogen concentrations are lower in men with HH. Men with diabesity and HH have more fat mass and are more insulin resistant than eugonadal men. In addition, they have a high prevalence of anemia and higher mortality rates than eugonadal men. Testosterone replacement therapy results in a loss of fat mass, gain in lean mass, and increase in insulin sensitivity in men with diabesity and HH. This is accompanied by an increase in insulin-signaling genes in adipose tissue and a reduction in inflammatory mediators that interfere with insulin signaling. There is also an improvement in sexual symptoms, anemia, LDL cholesterol, and lipoprotein (a). However, testosterone therapy does not consistently affect HbA_1c in men with diabetes. The effect of testosterone replacement on cardiovascular events or mortality in men with diabesity is not known and remains to be studied in prospective trials.

Does Obesity-Related Hemodilution of Carcinoembryonic Antigen Exist in Non-Small Cell Lung Cancer Patients?

Background

Previous investigations reported inverse relationship between prostate-specific antigen concentration and body mass index (BMI). These results have been explained by a hemodilution effect among obese men. However, the hemodilution of serum carcinoembryonic antigen (CEA) concentration in obese patients with non-small cell lung cancer (NSCLC) has not been ever reported.

Methods

Consecutive 381 NSCLC patients were enrolled. A body surface area (BSA)-based and a hematocrit (HCT)-based equations were applied for plasma volume (PV) estimation. The relationship between BMI and PV, serum CEA concentration and CEA amount, representing the total amount of CEA protein within the circulation, were examined.

Results

Higher BMI was significantly associated with higher PV (P < 0.001). However, serum CEA concentration was not significantly associated with increasing BMI. Furthermore, there was no significant association between BMI and CEA amount. The 5-year survival rate of patients with a high serum CEA concentration was significantly lower than that of patients with a normal CEA. There was no difference in the prognostic significance of serum CEA concentration and CEA amount.

Conclusions

We failed to find the association between BMI and CEA, suggesting no or small hemodilution effect of CEA in NSCLC patients. Furthermore, the measurement of the CEA amount could not provide any additional information.

The Correlation between Body Mass Index and Routine Parameters in Men Over Fifty

Purpose

This study aimed to investigate the relationships between body mass index (BMI) and prostate-specific antigen (PSA) levels, international prostate symptom score (IPSS), quality of life (QoL), and prostate volume (PV).

Materials and Methods

Height, weight, PSA levels, PV, and IPSS were analyzed in 15,435 patients who underwent a prostate examination between 2001 and 2014. Patients aged <50 years or with a PSA level ≥10 ng/mL were excluded. The relationships between BMI and PSA, IPSS, QoL, and PV were analyzed by a scatter plot, one-way analysis of variance, and the Pearson correlation coefficient.

Results

The mean age was 71.95±7.63 years, the mean BMI was 23.59±3.08 kg/m², the mean PSA level was 1.45±1.45 ng/mL, the mean IPSS was 15.53±8.31, the mean QoL score was 3.48±1.25, and the mean PV was 29.72±14.02 mL. PSA, IPSS, and QoL showed a tendency to decrease with increasing BMI, and there were statistically significant differences for each parameter (p≤0.001). PV showed a significant tendency to increase with BMI (p<0.001). In the correlation analysis, BMI showed a statistically significant correlation (p<0.001) with PSA, IPSS, and QoL, although the correlations were very weak. In contrast, BMI showed a significant correlation with PV (p<0.001), with a meaningful Pearson correlation coefficient of 0.124.

Conclusions

Higher BMI was associated with lower PSA levels and higher IPSS and QoL scores. Meanwhile, PV increased with BMI. Although obese individuals had a greater PV, obesity did not aggravate lower urinary tract symptoms.

Does obesity modify prostate cancer detection in a European cohort?

INTRODUCTION

To investigate prostate-specific antigen (PSA) accuracy and digital rectal examination (DRE) accuracy in detecting prostate cancer according to body mass index (BMI) in Spanish men with an indication of the first prostate biopsy.

MATERIAL AND METHODS

We reviewed the clinical and histopathological data of 1,319 patients who underwent transrectal ultrasound-guided prostate needle biopsy. The patients were categorised according to the BMI as follows: <25 kg/m² (normal weight); 25-29.9 kg/m² (overweight); and ≥30 kg/m² (obese). Receiver operator characteristic curves were used to assess PSA accuracy and DRE accuracy by calculating the area under the curve.

RESULTS

The obesity rate of the cohort was 14%. PSA accuracy for predicting prostate cancer in each BMI category was 0.52, 0.58 and 0.62, respectively (p = 0.01). After stratification by DRE findings, there was no difference in the performance accuracy of PSA in predicting the presence of cancer across BMI groups in abnormal DRE (p = 0.90). Serum PSA, DRE and BMI were strong predictors of prostate cancer diagnosis (odds ratio 1.07, 2.02 and 1.4, respectively; p <0.001). When the DRE was abnormal, a BMI ≥30 increased the risk of prostate cancer twice. With the addition of BMI to the model, the area under the curve of the combined PSA and DRE for diagnosing prostate cancer improved from 0.60 to 0.63.

CONCLUSIONS

The predictive value of PSA in predicting prostate cancer is not poorer in the obese population and the predictive value of an abnormal DRE in cancer detection is significantly modified by the patient's BMI.

Body mass index as a classifier to predict biochemical recurrence after radical prostatectomy in patients with lower prostate-specific antigen levels

Prostate cancer, one of the most common malignant tumors among men, is closely associated with obesity and, thus far, several studies have suggested the association between obesity and aggressive pathological characteristics in the United States. However, the effect of obesity on prostate cancer mortality is controversial, and it remains unclear whether obesity contributes to the aggressiveness of prostate cancer in Asian patients. The aim of the present study was to investigate the association between body mass index (BMI) and the clinicopathological characteristics of prostate cancer in 2,003 Japanese patients who underwent radical prostatectomy. There was a significant association between higher BMI and higher Gleason score (GS). The multivariate analysis also revealed that BMI was an independent indicator for GS ≥8 at surgery. Moreover, among patients with lower prostate-specific antigen levels, biochemical recurrence-free survival was significantly worse in those with higher BMI. These results suggest that BMI may be a classifier for predicting adverse pathological findings and biochemical recurrence after radical prostatectomy in Japanese patients.

The association between plasma C-peptide concentration and the risk of prostate cancer: a nested case-control study within a Japanese population-based prospective study

The association between plasma C-peptide concentration and prostate cancer is unclear. Inconsistency of results from previous studies motivates this study. Using the Japan Public Health Center-based Prospective study, 201 prostate cancer cases and 402 controls were matched by age, public health center area, residence, date and time of blood collection, and fasting duration before blood collection. Odds ratios (OR) and 95% confidence intervals (CIs) were estimated by conditional logistic regression models. Out of 201 cases, 144 were localized and 48 were advanced. The overall association between median plasma C-peptide concentration and prostate cancer was not significant (OR for the highest tertile=0.81, 95% CI: 0.43-1.56, P-trend=0.54). Although stratification of prostate cancer by stage indicated different effects of plasma C-peptide on localized and advanced cases, there was no association between plasma C-peptide concentration and advanced prostate cancer (OR=2.82, 95% CI: 0.30-26.36 for the highest category, P-trend=0.37) and localized cases (OR=0.49, 95% CI: 0.23-1.04 for the highest category, P-trend=0.06) for patients fasting at the time of blood collection. The association between plasma C-peptide concentration and prostate cancer risk differed by cancer stage. Differentiation of localized and advanced prostate cancer cases is crucial when investigating the association between plasma C-peptide concentration and the risk of prostate cancer.

Association of Obesity-Related Hemodilution of Prostate-Specific Antigen, Dihydrotestosterone, and Testosterone

BACKGROUND

Prostate-specific antigen (PSA) hemodilution is the leading theory for lower PSA values in obese men. However, testosterone and dihydrotestosterone (DHT), which are necessary for PSA production, are reduced in obese men. We assessed the relationship of body mass index (BMI) and PSA, taking into consideration the effect of testosterone and DHT.

METHODS

Among 8,122 participants in Reduction by Dutasteride of Prostate Cancer Events (REDUCE), complete data were available for 7,275. BMI was categorized as normal (<25 kg/m² ), overweight (25-29.9 kg/m² ), obese (30-34.9 kg/m² ), or moderate + severely obese (≥35 kg/m² ). Associations between BMI, testosterone, and DHT and the outcome variable of PSA were examined using linear regression.

RESULTS

There were 1,964 (27.0%) normal weight, 3,826 (52.6%) overweight, 1,200 (16.5%) obese, and 285 (3.9%) moderately + severely obese patients. With increasing BMI, there was a progressive decrease in PSA (P = 0.02), increase in prostate volume (P < 0.001), and decrease in both testosterone (P < 0.001) and DHT (P < 0.001). Using linear regression, increasing BMI was associated with decreasing serum PSA values. Furthermore, BMI remained inversely associated with PSA after individually adjusting for testosterone and DHT, as well as when adjusting for testosterone and DHT in the same model. Decreased androgen levels accounted for only 19% of the lower PSA in men with higher BMI.

CONCLUSIONS

Only a fraction of lower PSA in obese men could be attributed to testosterone and DHT levels. The remaining factors explaining lower PSA are unaccounted for, presumably secondary to hemodilution associated with increased plasma volume in obese men. Prostate 77:466-470, 2017. © 2016 Wiley Periodicals, Inc.

Prostate Cancer Detected by Screening in a Semi Urban Community in Southeast Nigeria: Correlations and Associations between Anthropometric Measurements and Prostate-specific Antigen

Context:

Prostate cancer (PCa) is frequently diagnosed at advanced stages in Nigeria.

Aims:

To determine the screen detected PCa prevalence in a suburban community and explore any relationships between prostate-specific antigen (PSA) and anthropometric measurements.

Settings and Design:

Nsukka is a town and local government area (LGA) in Southeast Nigeria in Enugu State. Towns that share a common border with Nsukka are Edem Ani, Alor-uno, Opi, Orba, and Ede-Oballa. Nsukka LGA has an area of 1810 km² and a population of 309,633 at the 2006 census. All consecutive responders who met the inclusion criteria were recruited.

Subjects and Methods:

A screening outreach was conducted in one location in Nsukka. PSA testing and digital rectal examinations were performed. Height and weight were measured and body mass index (BMI) was calculated.

Statistical Analysis Used:

Results were subjected to statistical analysis using SPSS 20 (IBM SPSS Statistics for Windows, Version 20.0. Armonk, NY, USA). Categorical data were analyzed using the Chi-square test, with significance level set at P < 0.05. Pearson's correlation was conducted for interval data (P < 0.05).

Results:

One-hundred and sixty men met the inclusion criteria and were screened. Age range was 40–81 years; PSA range was 1.20–33.9 ng/ml. Digital rectal examinations (DREs) was abnormal in 17 men. Median BMI was 27.49. A Pearson's correlation coefficient showed a significant correlation between age and PSA, r = 0.127; P ≤ 0.05, and DRE findings and PSA, r = 0.178; P ≤ 0.05. There was no significant correlation between height and PSA, r = −0.99; P = 0.211; weight and PSA, r = −0. 81 P = 0.308; and BMI and PSA, r = −0.066; P = 0.407. 8/21 men consented to prostate biopsy with three positive, giving a screen detected PCa prevalence of 1.875%.

Conclusions:

Screen detected PCa prevalence in high this population and efforts to improve early detection may be of value in improving treatment outcomes.

Investigating the prostate specific antigen, body mass index and age relationship: is an age-BMI-adjusted PSA model clinically useful?

PURPOSE

Previous studies indicate a possible inverse relationship between prostate-specific antigen (PSA) and body mass index (BMI), and a positive relationship between PSA and age. We investigated the associations between age, BMI, PSA, and screen-detected prostate cancer to determine whether an age-BMI-adjusted PSA model would be clinically useful for detecting prostate cancer.

METHODS

Cross-sectional analysis nested within the UK ProtecT trial of treatments for localized cancer. Of 18,238 men aged 50-69 years, 9,457 men without screen-detected prostate cancer (controls) and 1,836 men with prostate cancer (cases) met inclusion criteria: no history of prostate cancer or diabetes; PSA < 10 ng/ml; BMI between 15 and 50 kg/m2. Multivariable linear regression models were used to investigate the relationship between log-PSA, age, and BMI in all men, controlling for prostate cancer status.

RESULTS

In the 11,293 included men, the median PSA was 1.2 ng/ml (IQR: 0.7-2.6); mean age 61.7 years (SD 4.9); and mean BMI 26.8 kg/m2 (SD 3.7). There were a 5.1% decrease in PSA per 5 kg/m2 increase in BMI (95% CI 3.4-6.8) and a 13.6% increase in PSA per 5-year increase in age (95% CI 12.0-15.1). Interaction tests showed no evidence for different associations between age, BMI, and PSA in men above and below 3.0 ng/ml (all p for interaction >0.2). The age-BMI-adjusted PSA model performed as well as an age-adjusted model based on National Institute for Health and Care Excellence (NICE) guidelines at detecting prostate cancer.

CONCLUSIONS

Age and BMI were associated with small changes in PSA. An age-BMI-adjusted PSA model is no more clinically useful for detecting prostate cancer than current NICE guidelines. Future studies looking at the effect of different variables on PSA, independent of their effect on prostate cancer, may improve the discrimination of PSA for prostate cancer.

Difference in Association of Obesity With Prostate Cancer Risk Between US African American and Non-Hispanic White Men in the Selenium and Vitamin E Cancer Prevention Trial (SELECT)

IMPORTANCE

African American men have the highest rates of prostate cancer incidence and mortality in the United States. Understanding underlying reasons for this disparity could identify preventive interventions important to African American men.

OBJECTIVE

To determine whether the association of obesity with prostate cancer risk differs between African American and non-Hispanic white men and whether obesity modifies the excess risk associated with African American race.

DESIGN, SETTING, AND PARTICIPANTS

Prospective study of 3398 African American and 22,673 non-Hispanic white men who participated in the Selenium and Vitamin E Cancer Prevention Trial (2001-2011) with present analyses completed in 2014.

MAIN OUTCOMES AND MEASURES

Total, low-grade (Gleason score <7), and high-grade (Gleason score ≥7) prostate cancer incidence.

RESULTS

With a median (interquartile range) follow-up of 5.6 (1.8) years, there were 270, 148, and 88 cases of total, low-, and high-grade prostate cancers among African American men and a corresponding 1453, 898, and 441 cases in non-Hispanic white men, respectively. Although not associated with risk among non-Hispanic white men, BMI was positively associated with an increase in risk among African American men (BMI, <25 vs ≥35: hazard ratio [HR], 1.49 [95% CI, 0.95, 2.34]; P for trend = .03). Consequently, the risk associated with African American race increased from 28% (HR, 1.28 [95% CI, 0.91-1.80]) among men with BMI less than 25 to 103% (HR, 2.03 [95% CI, 1.38-2.98]) among African American men with BMI at least 35 (P for trend = .03). Body mass index was inversely associated with low-grade prostate cancer risk within non-Hispanic white men (BMI, <25 vs ≥35: HR, 0.80 [95% CI, 0.58-1.09]; P for trend = .02) but positively associated with risk within African American men (BMI, <25 vs ≥35: HR, 2.22 [95% CI, 1.17-4.21]; P for trend = .05). Body mass index was positively associated with risk of high-grade prostate cancer in both non-Hispanic white men (BMI, <25 vs ≥35: HR, 1.33 [95% CI, 0.90-1.97]; P for trend = .01) and African American men, although the increase may be larger within African American men, albeit the racial interaction was not statistically significant (BMI, <25 vs ≥35: HR, 1.81 [95% CI, 0.79-4.11]; P for trend = .02).

CONCLUSIONS AND RELEVANCE

Obesity is more strongly associated with increased prostate cancer risk among African American than non-Hispanic white men and reducing obesity among African American men could reduce the racial disparity in cancer incidence. Additional research is needed to elucidate the mechanisms underlying the differential effects of obesity in African American and non-Hispanic white men.

Associations of body mass index, smoking, and alcohol consumption with prostate cancer mortality in the Asia Cohort Consortium

Many potentially modifiable risk factors for prostate cancer are also associated with prostate cancer screening, which may induce a bias in epidemiologic studies. We investigated the associations of body mass index (weight (kg)/height (m)(2)), smoking, and alcohol consumption with risk of fatal prostate cancer in Asian countries where prostate cancer screening is not widely utilized. Analysis included 18 prospective cohort studies conducted during 1963-2006 across 6 countries in southern and eastern Asia that are part of the Asia Cohort Consortium. Body mass index, smoking, and alcohol intake were determined by questionnaire at baseline, and cause of death was ascertained through death certificates. Analysis included 522,736 men aged 54 years, on average, at baseline. During 4.8 million person-years of follow-up, there were 634 prostate cancer deaths (367 prostate cancer deaths across the 11 cohorts with alcohol data). In Cox proportional hazards analyses of all cohorts in the Asia Cohort Consortium, prostate cancer mortality was not significantly associated with obesity (body mass index >25: hazard ratio (HR) = 1.08, 95% confidence interval (CI): 0.85, 1.36), ever smoking (HR = 1.00, 95% CI: 0.84, 1.21), or heavy alcohol intake (HR = 1.00, 95% CI: 0.74, 1.35). Differences in prostate cancer screening and detection probably contribute to differences in the association of obesity, smoking, or alcohol intake with prostate cancer risk and mortality between Asian and Western populations and thus require further investigation.

Total, free, and complexed prostate-specific antigen levels among US men, 2007-2010

BACKGROUND

Screening for prostate cancer using prostate-specific antigen (PSA) is common. Prostate cancer has been associated with higher total PSA (tPSA), lower free PSA (fPSA), lower percent free PSA (%fPSA), and higher complexed PSA (cPSA).

METHODS

Total, free and complexed PSAs were performed on 3251 men ≥40years in the 2007-2010 National Health and Nutrition Examination Survey. Distributions of the PSA tests were examined by age, race and ethnicity, and body mass index (BMI) groups. Percentages of men at PSA thresholds were examined.

RESULTS

Total PSA geometric mean was 0.96μg/l among men aged ≥40years and increased from 0.74μg/l for men 40-49years, to 1.82μg/l for men 80years and older. Non-Hispanic Whites had lower age-adjusted mean tPSA (1.03μg/l) and cPSA (0.56μg/l) than non-Hispanic Blacks (tPSA 1.25μg/l and cPSA 0.72μg/l). Obese men had lower age-adjusted mean total, free and complexed PSAs (0.94, 0.27, and 0.51μg/l, respectively) than men with normal BMI (tPSA 1.21, fPSA 0.32, and cPSA 0.68μg/l, respectively).

CONCLUSION

Total, free and complexed PSAs increased with age; tPSA and cPSAs were highest in non-Hispanic Blacks; and total, free, and complexed PSAs were lowest in obese men.

Higher body mass index increases the risk for biopsy-mediated detection of prostate cancer in Chinese men

Objective

To investigate the relationship between body mass index (BMI) and prostate cancer (PCa) risk at biopsy in Chinese men.

Patients and Methods

We retrospectively reviewed the records of 1,807 consecutive men who underwent initial multicore (≥10) prostate biopsy under transrectal ultrasound guidance between Dec 2004 and Feb 2014. BMI was categorised based on the Asian classification of obesity as follows: <18.5 (underweight), 18.5–22.9 (normal weight), 23–24.9 (overweight), 25–29.9 (moderately obese), and ≥30 kg/m2 (severely obese). The odds ratios (OR) of each BMI category for risk of PCa and high-grade prostate cancer (HGPCa, Gleason score ≥4+3) detection were estimated in crude, age-adjusted and multivariate-adjusted models. Prevalence ratios and accuracies of PSA predicted PCa were also estimated across BMI groups.

Results

In total, PCa was detected by biopsy in 750 (45.4%) men, and HGPCa was detected in 419 (25.4%) men. Compared with men of normal weight, underweight men and obese men were older and had higher prostate specific antigen levels. The risk of overall PCa detection via biopsy presented an obvious U-shaped relationship with BMI in crude analysis. Overall, 50.0%, 37.4%, 45.6% 54.4% and 74.1% of the men in the underweight, normal weight, overweight, moderately obese and severely obese groups, respectively, were diagnosed with PCa via biopsy. In multivariate analysis, obesity was significantly correlated with a higher risk of PCa detection (OR = 1.17, 95%CI 1.10–1.25, P<0.001). However, higher BMI was not correlated with HGPCa detection (OR = 1.03, 95%CI 0.97–1.09, P = 0.29). There were no significant differences in the accuracy of using PSA to predict PCa or HGPCa detection across different BMI categories.

Conclusion

Obesity was associated with higher risk of PCa detection in the present Chinese biopsy population. No significant association was detected between obesity and HGPCa.

Can metabolic disorders in aging men contribute to prostatic hyperplasia eligible for transurethral resection of the prostate (TURP)?

PURPOSE

The aim of this study was to evaluate the incidence and severity of metabolic disorders occurring in the metabolic syndrome in patients with benign prostatic hyperplasia eligible for surgical treatment.

METHODS

The study group consisted men with diagnosed benign prostatic hyperplasia. The control group consisted patients recruited from basic health care units. Abdominal circumference, body weight and blood serum metabolic parameters were determined in the experimental and control groups. The concentrations of glucose were determined, as well as total cholesterol (ChT), low-density lipoprotein (LDL), high density lipoprotein (HDL) and triglycerides (TAG), by spectrophotometric method using reagent kits.

RESULTS

In the study group 91 (60.3%) cases of metabolic syndrome (MetS) were diagnosed, while in the control group 71 (46.1%) men met the diagnostic criteria for this syndrome (p=0.018). The analysis shows a relationship between MetS in patients with BPH and concentration glucose, ChT, LDL, HDL, systolic blood pressure and diastolic blood pressure. We found no significant statistical relationship between body weight, abdominal circumference and concentration TAG, hypertension in patients and controls.

CONCLUSIONS

in the study presented in this article, statistically significant relationships between BPH and the diagnostic parameters of the metabolic syndrome were demonstrated. These results indicate to the necessity of the modification of the lifestyle, taking preventive measures in diabetes, and evaluation of lipid metabolism disorders. It is recommended to assess symptoms that may suggest BPH (as a manifestation of LUTS) in men over 50 years of age with diagnoses of metabolic disorders (including MetS), and provide them with specialist urological care in order to prevent surgical treatment of the prostate.

Poor glycemic control is associated with reduced prostate specific antigen concentrations in men with type 1 diabetes

PURPOSE

Previous studies have revealed lower prostate specific antigen concentrations in men with type 2 diabetes, paralleling the reported lower prevalence of prostate cancer in diabetic men. Data are lacking on prostate specific antigen in men with type 1 diabetes whose insulin and obesity profiles differ from those with type 2 diabetes mellitus. In this study we examined the relationship between long-term glycemic control and prostate specific antigen in men with type 1 diabetes mellitus.

MATERIALS AND METHODS

Total prostate specific antigen was measured at one time in 639 men in the EDIC, the observational followup of participants in the DCCT. The relationship between DCCT/EDIC weighted mean hemoglobin A1c and log prostate specific antigen was assessed using linear regression modeling after adjusting for age, body mass index, total testosterone, statin and thiazide medication use, diabetes duration, and DCCT randomization arm and cohort.

RESULTS

Median subject age was 52 years, body mass index was 28.4 kg/m(2) and DCCT/EDIC time-weighted hemoglobin A1c was 7.9%. Median prostate specific antigen was 0.64 ng/ml (IQR 0.43, 1.05). Prostate specific antigen increased significantly with age (p <0.0001) and with lower time-weighted hemoglobin A1c (p <0.0001). Each 10% increase in hemoglobin A1c was accompanied by an 11% reduction in prostate specific antigen (p=0.0001).

CONCLUSIONS

Prostate specific antigen decreases as hemoglobin A1c increases in men with type 1 diabetes mellitus. This relationship is independent of age, body mass index, androgen levels, medication use and measures of diabetes severity, which suggests that factors related to glycemia may directly affect prostate specific antigen levels.

Obesity affects the biopsy-mediated detection of prostate cancer, particularly high-grade prostate cancer: a dose-response meta-analysis of 29,464 patients

BACKGROUND AND OBJECTIVES

In previous studies, obesity (measured according to the body mass index) has correlated inconsistently with the risk of biopsy-measured prostate cancer, and specifically high-grade prostate cancer. This meta-analysis aimed to clarify these correlations.

METHODS

A comprehensive literature search of the MEDLINE and EMBASE databases was conducted for relevant studies published through January 2014. The pooled estimates of odds ratios (OR) and confidence intervals (CI) were computed, and the meta-analysis was performed with the STATA software according to a random effects approach.

RESULTS

A total of 11 studies that included 29,464 individuals were identified. A 5-kg/m2 increase in body mass index was associated with a 15% (OR, 1.15; 95% CI, 0.98-1.34) higher risk of prostate cancer detection and a 37% (OR, 1.37; 95% CI, 1.19-1.57) higher risk of high-grade prostate cancer detection at biopsy. There were no differences among the results of studies conducted in the USA, Europe or Asia. We also found that studies that had adjusted for prostate-specific antigen levels, digital rectal examination results, and prostate volumes obtained positive significant outcomes (OR, 1.27; 95% CI, 1.12-1.44), whereas studies that did not adjust for the above-mentioned confounding variables obtained negative results (OR, 0.92; 95% CI, 0.68-1.25). Moreover, the positive correlation between body mass index and the detection of both prostate cancer and high-grade diseases tended to be stronger as the number of biopsy cores increased.

CONCLUSION

The present meta-analysis demonstrated that a high body mass index correlated positively with prostate cancer detection, especially high-grade prostate cancer detection. The adoption of a modified and possibly more aggressive biopsy strategy was suggested for obese populations.

Is there a role for body mass index in the assessment of prostate cancer risk on biopsy?

PURPOSE

We examine the role of body mass index in the assessment of prostate cancer risk.

MATERIALS AND METHODS

A total of 3,258 participants who underwent biopsy (including 1,902 men with a diagnosis of prostate cancer) were identified from the Selenium and Vitamin E Cancer Prevention Trial. The associations of body mass index with prostate cancer and high grade prostate cancer were examined using logistic regression, adjusting for age, race, body mass index adjusted prostate specific antigen, digital rectal examination, family history of prostate cancer, biopsy history, prostate specific antigen velocity, and time between study entry and the last biopsy. The prediction models were compared with our previously developed body mass index adjusted Prostate Cancer Prevention Trial prostate cancer risk calculator.

RESULTS

Of the study subjects 49.1% were overweight and 29.3% were obese. After adjustment, among men without a known family history of prostate cancer, increased body mass index was not associated with a higher risk of prostate cancer (per one-unit increase in logBMI OR 0.83, p=0.54) but was significantly associated with a higher risk of high grade prostate cancer (ie Gleason score 7 or greater prostate cancer) (OR 2.31, p=0.03). For men with a known family history of prostate cancer the risks of prostate cancer and high grade prostate cancer increased rapidly as body mass index increased (prostate cancer OR 3.73, p=0.02; high grade prostate cancer OR 7.95, p=0.002). The previously developed risk calculator generally underestimated the risks of prostate cancer and high grade prostate cancer.

CONCLUSIONS

Body mass index provided independently predictive information regarding the risks of prostate cancer and high grade prostate cancer after adjusting for other risk factors. Body mass index, especially in men with a known family history of prostate cancer, should be considered for inclusion in any clinical assessment of prostate cancer risk and recommendations regarding prostate biopsy.

Association between obesity, prostate-specific antigen level and prostate-specific antigen density in men with a negative prostate biopsy

OBJECTIVE

To determine the association between body mass index (BMI), serum prostate-specific antigen (PSA) level and PSA density (PSAD) in patients with an elevated serum PSA level but a negative prostate biopsy.

METHODS

This retrospective study enrolled men with a negative prostate biopsy but a serum PSA level of 3.0-10 ng/ml. All men underwent anthropometric measurements, serum PSA determination and transrectal ultrasound examination. BMI was grouped according to the Asia-Pacific obesity criteria: nonobese (<25 kg/m(2)) versus obese (≥ 25 kg/m(2)). Partial correlation and linear regression models between PSA, PSAD and BMI were conducted after adjusting for age.

RESULTS

A total of 907 men were enrolled in this study. On multivariate analyses, PSA showed no significant correlation with age or BMI, whereas PSAD had a negative correlation with age and BMI. Similar results were obtained when patients were categorized as having low (3.0 < PSA  ≤ 6.5 ng/ml) or high PSA (6.5 < PSA ≤ 10.0 ng/ml) levels.

CONCLUSION

PSAD, but not PSA, demonstrated a significant negative correlation with BMI. This indicates that a new strategy including PSAD rather than simple PSA levels should be adopted in the study of obesity-adjusted PSA cut-offs.

Impact of body mass index on clinicopathological outcome and biochemical recurrence after radical prostatectomy

BACKGROUND

Accumulating evidence suggests that obesity is associated with tumor progression in prostate cancer (PCa) patients after radical prostatectomy (RP). We conducted a retrospective multicenter study to determine the effect of body mass index (BMI) on the clinicopathological characteristics and biochemical recurrence of PCa in Japanese men who underwent RP.

METHODS

The medical records of 1257 men with PCa treated by RP without neoadjuvant therapy at four medical institutes between 2001 and 2009 were retrospectively reviewed. Patients were categorized into four groups using the World Health Organization (WHO) BMI classification and BMI quartiles. Associations of the various BMI categories with clinicopathological characteristics and biochemical recurrences were statistically evaluated. Biochemical recurrence was defined as a PSA level of >0.2 ng ml(-1).

RESULTS

Of the 1257 patients, 230 (18.3%) experienced biochemical recurrence during the median follow-up period of 49 months. The median BMI was 23.8 kg m(-2), and 1.4% patients were underweight, 65.4% were of normal weight, 30.9% were overweight and 2.4% were obese (WHO classification). Preoperative PSA levels and PSA density (PSAD) tended to decrease as BMI increased. Pathological characteristics did not differ significantly among BMI categories. As per the WHO classification and quartile categories, biochemical recurrence rate was comparable among the BMI groups. After adjusting for other pre- and postoperative covariables, multivariate Cox proportional hazards analysis revealed that a high BMI did not have an independent impact on biochemical recurrence-free survival.

CONCLUSIONS

Underweight Japanese PCa patients treated by RP had higher preoperative PSA levels and PSAD. High BMI was not associated with adverse pathological findings or increased biochemical recurrence rate in Japanese PCa patients treated with RP. Racial differences may exist in the relationship between obesity and outcomes of RP in PCa patients.

Screening for prostate cancer: an updated review

Prostate cancer is the most frequently diagnosed malignancy in men and its incidence has been increasing in the last decades. Diagnosis and treatment of prostate cancer were radically improved after the discovery of prostatic-specific antigen. Early detection rates increased, especially in asymptomatic individuals, confirmed by recent published randomized trials. The impact of screening in overdiagnosis and overtreatments is discussed, since benefits in overall mortality rates were not clearly demonstrated. Perhaps younger patients with a longer life expectancy would be the ones with the most benefits from screening. This study presents an update of the most important screening methods for prostate cancer as well as the recent recommendations for screening.

Relationship between prostate-specific antigen, age, and body mass index in a prostate cancer screening population

BACKGROUND

Recent studies questioning the benefit of prostate-specific antigen (PSA) screening have increased the need for evaluating factors contributing to variance in levels and their clinical relevance. An inverse relationship between body mass index (BMI) and PSA has been illustrated, however the clinical implications have not been specified. We performed a retrospective review of patients screened through our free screening clinic to delineate any relationship between PSA and BMI in an attempt to understand its possible clinical significance.

METHODS

The authors retrospectively reviewed data collected in relation to PSA values and patient characteristics from a community outreach program supplying information and screening for prostate cancer between June of 2003 and August of 2009.

RESULTS

Mean BMI of our patient population was 28.7 m/kg(2) (SD 5.4) and our mean PSA value was 1.28 (SD 1.77). Our data indicate a small, but statistically significant decrease in PSA for an increasing BMI with a 0.026 decrease in PSA for every unit increase in BMI.

CONCLUSIONS

Our study confirms the previously reported inverse relationship between PSA value and BMI. The significance of this finding and its impact on the value do not seem to indicate a rationale to change the accepted abnormal value in obese patients and should be used in the context of the clinical scenario and other PSA altering factors.

The impact of obesity on the predictive accuracy of PSA in men undergoing prostate biopsy

PURPOSE

Obese men have been reported to have lower serum PSA values relative to normal-weight men in population-based studies, screening cohorts, and in men with prostate cancer (CaP) treated with surgery. There are concerns that PSA may be less accurate in detecting prostate cancer in men with increased body mass index (BMI). We determine whether the diagnostic potential of PSA is negatively influenced by obesity by comparing its operating characteristics across BMI categories among men undergoing prostate biopsy.

METHODS

Demographic, clinical, and histopathological data on 917 men who underwent trans-rectal ultrasound-guided prostate needle biopsy from 2002 to 2010 at a University hospital in Italy were used in the study. Men were categorized for BMI as follows: <25 kg/m(2) (normal weight), 25-29.9 kg/m(2) (overweight), and ≥ 30 kg/m(2) (obese). Receiver operator characteristics (ROC) curves were used to assess PSA accuracy for predicting prostate cancer overall and then stratified according to digital rectal examination (DRE) findings using the area under the ROC curve (AUC).

RESULTS

The obesity rate of the study cohort was 21 %. There was no statistically significant difference in the overall AUCs of PSA for predicting CaP among normal-weight (AUC = 0.56), overweight (AUC = 0.60), and obese men (AUC = 0.60; p = 0.68) in either DRE-positive or negative men.

CONCLUSIONS

In a cohort of Italian men undergoing prostate biopsy, the performance accuracy of PSA as a predictor of CaP is not significantly altered by BMI. Obesity does not negatively impact the overall ability of PSA to discriminate between CaP and benign conditions.

Performance of prostate-specific antigen mass in estimation of prostate volume in Japanese men with benign prostate hyperplasia

OBJECTIVES

Obese men with benign prostate hyperplasia might have lower serum prostate-specific antigen because of hemodilution, resulting in underestimation of total prostate volume by serum prostate-specific antigen. The aim of this study was to compare the performance of prostate-specific antigen mass as the absolute amount of prostate-specific antigen protein secreted into circulation with that of serum prostate-specific antigen in the prediction of total prostate volume.

METHODS

A total of 1517 men with serum prostate-specific antigen up to 10 ng/mL, including 1425 with biopsy-proven benign prostate hyperplasia, were enrolled in this study. Height and weight were used to estimate body mass index, body surface area and plasma volume. Prostate-specific antigen mass was calculated as serum prostate-specific antigen multiplied by plasma volume. The association between serum prostate-specific antigen or prostate-specific antigen mass and transrectal ultrasound-measured total prostate volume were evaluated by Pearson's correlation coefficient (Υ), linear regression analyses and receiver operating characteristic curves.

RESULTS

Serum prostate-specific antigen had an inverse relationship with plasma volume, decreasing as plasma volume increased, after adjustment of total prostate volume. Larger total prostate volume per serum prostate-specific antigen was found in men with higher body mass index or plasma volume. Among all participants, the correlation (Υ = 0.456) between prostate-specific antigen mass and total prostate volume was apparently stronger than that (Υ = 0.442) between serum prostate-specific antigen and total prostate volume. Prostate-specific antigen mass outperformed serum prostate-specific antigen at estimating total prostate volume cut-off values of 30 and 40 mL. These findings were more significant in men aged ≥60 years.

CONCLUSIONS

Prostate-specific antigen mass performs better than serum prostate-specific antigen in estimating TPV, especially in men aged ≥60 years.

A Review on the Clinical Utility of PSA in Cancer Prostate

Prostate cancer has come to share the oncological centrestage among male cancers. The availability of Serum Prostate Specific Antigen, PSA, as a marker has encouraged it's use to diagnose both cancer and cancer recurrence. Some clarity is required about its precise role in clinical practice. The available literature on Prostate Specific Antigen was reviewed; Articles were reviewed for content, applicability to the problem at hand, availability of data about sensitivity and specificity of values, refinements in measurements and finally for impact of screening programmes using these values on survival and quality of life. The data in the literature was critically re-evaluated and analysed to draw reasonable conclusions. Serum PSA measurements show variable reliability when it comes to diagnosis of Prostate cancer, given the dynamics of PSA physiology. Surrogate measures like PSA density, PSA velocity, free-to-complexed PSA ratio, percentage Pro-PSA, etc., have been used to improve the predictive utility of this assay for Prostate cancer. The ability of PSA to detect those cancers that will cost life, and thereby permit early curative treatment, is as yet unclear. It's most definitive role appears to be in diagnosing recurrences after adequate surgical treatment, and in evaluating response to treatment.

Which obesity index best correlates with prostate volume, prostate-specific antigen, and lower urinary tract symptoms?

OBJECTIVE

To determine which measurement variable, waist circumference (WC), body mass index (BMI), or waist-to-hip ratio (WHR) is most closely related to the prostate volume (PV), prostate-specific antigen (PSA), and lower urinary tract symptoms (LUTS).

METHODS

Between January 2010 and September 2011, 1632 consecutive ostensibly healthy Korean men aged 40-69 years who visited our clinic for a prostate checkup were enrolled into the study. Exclusion criteria included pyuria, history of lower urinary tract disorder influencing urination, and a high PSA level of >3.0 ng/mL. All men underwent a detailed clinical evaluation using the International Prostate Symptom Score (I-PSS) questionnaire. Anthropometric measurements were determined. Serum PSA, urinalysis, and transrectal ultrasound were also performed.

RESULTS

Data from 1601 men were analyzed. The mean age was 51.6 years, WC 83.7 cm, BMI 24.8 kg/m(2), PV 24.6 mL, and the mean PSA level was 1.07 ng/mL. Using multivariate analysis, PV most positively associated with WC (P < .001), while PSA level had negatively associated with BMI (P = .036) and no significant association with WC or WHR was noted. There was no significant relationship between various obesity indexes and I-PSS.

CONCLUSION

Our data showed that PV positively associated with central obesity, as represented by WC. In contrast, serum PSA negatively associated with BMI, which represented overall obesity (ie, hemodilution). Our data also suggested that obesity is not associated with lower urinary tract symptoms in Korean men.

Serum prostate specific antigen changes in cynomolgus monkeys (Macaca fascicularis) on a high sugar high fat diet

BACKGROUND

An inverse relationship between serum prostate specific antigen (PSA) levels and body mass index (BMI) has been reported in men but not in any animal model.

METHODS

Serum PSA in a colony of cynomolgus monkeys was assayed and correlated to body weight, prostate weight, and age. In addition, 15 animals were selected and fed a high sugar high fat (HSHF) diet for 49 weeks to increase their BMI and correlate it to PSA RESULTS: Serum PSA levels were positively correlated to prostate weight (r = 0.515, P = 0.025) and age (r = 0.548, P = 0.00072) but was not significantly correlated to body weight (r = -0.032, P = 0.419). For the animals on the HSHF diet, body weight, lean mass, fat mass, and BMI were significantly higher at 49 weeks than at baseline (P < 0.01). PSA was not significantly correlated to body weight and insulin at both baseline and 49 weeks. PSA was negatively correlated to BMI and insulin resistance (HOMA-IR) at 49 weeks but not at baseline. In addition, we observed hepatic steatosis and increases in serum liver enzymes.

CONCLUSIONS

Increases in BMI in cynomolgus monkeys as a result of consuming a HSHF diet resulted in PSA changes similar to those in humans with increased BMI. Cynomolgus monkeys are a useful model for investigating the relationship between obesity, diabetes, and PSA changes resulting from prostate gland pathology.

Association between smoking status, and free, total and percent free prostate specific antigen

PURPOSE

There are scant data available on the relationship between smoking and total prostate specific antigen, free prostate specific antigen and percent-free prostate specific antigen. Given the high prevalence of smoking and the frequency of prostate specific antigen screening, it is important to determine any association between smoking and prostate specific antigen values using nationally representative data.

MATERIALS AND METHODS

Included in the final study population were 3,820 men 40 years old or older who participated in the 2001-2006 NHANES (National Health and Nutrition Examination Survey) and met the eligibility criteria for prostate specific antigen testing. The distributions of total, free and percent free prostate specific antigen were estimated by sociodemographic and clinical characteristics. Multivariate linear regression models were fit to determine the adjusted relationship between smoking and total and percent free prostate specific antigen while simultaneously controlling for these characteristics.

RESULTS

For all ages combined the median total and free prostate specific antigen levels were 0.90 (0.81-0.90) and 0.26 (0.25-0.28) ng/ml, respectively. Multivariate linear regression analysis showed that total prostate specific antigen was 7.9% and 12.2% lower among current and former smokers, respectively, than among never smokers. High body mass index and diabetes were also statistically significantly associated with a lower total prostate specific antigen. Approximately a third of the men had a percent free prostate specific antigen less than 25%. Current smokers had a significantly lower percent free prostate specific antigen than former smokers.

CONCLUSIONS

Our finding that smoking is inversely associated with total prostate specific antigen may have potential implications for the interpretation of prostate specific antigen levels in men who are current or former smokers. Given the high prevalence of smoking, obesity and diabetes, additional research on the combined effect of these health risk factors is warranted.