Ethnic differences in the age-related distribution of serum prostate-specific antigen values: a study in a healthy Korean male population

Ethnic differences in the age-related distribution of serum prostate-specific antigen values: A study in a Taiwanese male population

This study investigates age-specific prostate-specific antigen (PSA) distributions in Taiwanese men and recommends reference ranges for this population after comparison with other studies. From January 1999 to December 2016, a total of 213,986 Taiwanese men aged above 19 years old without history of prostate cancer, urinary tract infection, or prostate infection were recruited from the Taiwan MJ cohort, an ongoing prospective cohort of health examinations conducted by the MJ Health Screening Center in Taiwan. Participants were divided into seven age groups. Simple descriptive statistical analyses were carried out and quartiles and 95th percentiles were calculated for each group as reference ranges for serum PSA in screening for prostate cancer in Taiwanese men. Serum PSA concentration correlated with age (r = 0.274, p<0.001). The median serum PSA concentration (5th to 95th percentile) ranged from 0.7 ng/ml (0.3 to 1.8) for men 20-29 years old (n = 6,382) to 1.6 ng/ml (0.4 to 8.4) for men over 79 years old (n = 504). The age-specific PSA reference ranges are as follows: 20-29 years, 1.80 ng/ml; 30-39 years, 1.80 ng/ml; 40-49 years, 2.0 ng/ml; 50-59 years, 3.20 ng/ml; 60-69 years, 5.60 ng/ml; 70-79 years, 7.40 ng/ml; over 80 years, 8.40 ng/ml. Almost no change occurred in the median serum PSA value in men 50 years old or younger, while a gradual increase was observed in men over 50. Taiwanese men aged 60 years above showed higher 95th percentile serum PSA values compared to Caucasian men and men in other Asian countries but were closer to those of Asian American and African American men. Results indicate significantly different PSA levels correlating to different ethnicities, suggesting that Oesterling's age-specific PSA reference ranges might not be appropriate for Taiwanese men. Our results should be further studied to validate the age-specific PSA reference ranges for Taiwanese men presented in this study.

Determination of Serum Prostate Specific Antigen Levels Amongst Apparently Healthy Nigerian Males in a University and University Hospital Community in the Federal Capital Territory

BACKGROUND

Prostate cancer is the commonest cancer among men worldwide and serum prostate specific antigen (PSA) has remained the most commonly applied screening test for the disease till date. Current PSA test results guidelines in our population are informed by reference intervals derived from studies from Caucasians and other racial groups. With scanty data on PSA reference values from our local population, this study evaluated the serum PSA levels of apparently healthy Nigerian male subjects in whom prostate cancer and urinary tract infection have been excluded.

METHOD

This study had participants aged 40 to 70 years, with no lower urinary tract symptoms or other symptoms suggestive of prostate disease recruited from the male staff population of the University of Abuja and University of Abuja Teaching Hospital and the adjoining local community. They were physically examined, had prostate ultrasonography, urine analysis, and blood sample collected for PSA testing. Data collected was analyzed using Statistical Package for Social Science (SPSS) version 24.

RESULT

Of a total of 210 men who participated in the study, 191 eventually met the inclusion criteria. The average age was 52.9 years, ninety seven percent of them had heard of prostate cancer before now. The mean total PSA was 1.46 ng/mL (SD +/-1.55), while the reference interval was .23-5.60 ng/mL. The average prostate size was 41.8 mL (SD+/-20.11), and there was a positive correlation between the PSA and the prostate size (.418) as well as the age of the subjects (.446). There was no significant difference in the mean PSA value for those with or without family history of prostate cancer (P=.979).

CONCLUSION

The reference range of PSA in Nigeria is higher than in other races, hence utilizing a local value in decision making would help to reduce unnecessary invasive procedures.

Age-Adjusted Reference Values for Prostate Specific Antigen - A Systematic Review and Meta-Analysis

OBJECTIVES

To systematically evaluates the evidence on ethnic differences in age-adjusted reference values of PSA.

MATERIALS AND METHODS

In concordance with the Preferred Reporting Items for Systematic Review and Meta-analysis statement, a review of English articles using Medline, Embase and Cochrane databases, from inception to December 2019 was conducted. Studies that reported the PSA upper reference value as 95th percentile of the cohort distribution, in healthy men aged 40 to 79, were included. Methodological quality was assessed with a modified version of the Agency for Healthcare Research and Quality checklist for cross-sectional studies.

RESULTS

Forty-three studies examining 325,514 participants were included in the analysis. These were published between 1993 and 2018. Majority were prospective observational studies and reported the reference values in ten-year age intervals. Only five reports directly compared ethnic differences in PSA values. Due to missing data, six studies were not considered in the quantitative synthesis. For the remainder (37/43), heterogeneity in PSA reference values was considerable (Higgin's index = 99.2%), with age and ethnicity being the sole identified significant contributors. Accordingly, the pooled upper limits for PSA reference values were 2.1, 3.2, 4.9 and 6.5 ng/ml for men in their 40 s, 50 s, 60 s, and 70 s, respectively.

CONCLUSION

Moderate quality evidence suggest that upper PSA reference limits increased with age and significant ethnic differences were present.

Relationship between serum prostate-specific antigen and transrectal prostate sonographic findings in asymptomatic Ugandan males

Background

Prostate disorders are among the leading causes of morbidity and mortality in men above the age of 40 years globally. Serum prostate-specific antigen (PSA) levels may be used to screen men at risk of prostate cancer and determine choice of medical treatment in benign prostatic hyperplasia (BPH) and evaluation of patients with prostatitis, while prostate sonography determines prostate volume (PV) and detects nodules. BPH may exhibit distinct hypoechoic, isoechoic, or hyperechoic nodules in the transition zone, whereas hypoechoic nodules in the peripheral zone are diagnostic for prostate cancer in over 50% of cases. In this study, we aimed at determining the relationship between serum PSA levels and transrectal prostate sonographic findings among asymptomatic Ugandan males.

Methods

Ugandan males above 30 years of age or older without lower urinary tract symptoms were cross-sectionally enrolled into the study. Serum PSA determination and transrectal ultrasound were performed. Association between PSA levels and PV was assessed using Spearman’s correlation coefficients (ρ).

Results

A total of 277 men were studied. The median serum PSA level was 1 (95% CI: 1–2). Most (n = 217, 78.3%) participants had serum PSA levels ≤ 4 ng/ml. The median sonographic PV was 26 (95% CI: 26–29) mls. One hundred and fifty-five (56.0%) participants had PV between 25 and 50 mls. Both PSA levels and PV progressively increased with age from 0.9 ng/ml and 22 mls in the 30–39 year age group to 7 ng/ml and 38 mls in the 60–69 year age group, respectively. PSA levels weakly correlated with PV (ρ = 0.27) (p < 0.0001). One hundred and thirty (47%) participants had prostatic nodules. Of these, 100 (77%) had features of benign nodules and 23% had suspicious nodules for prostate cancer. The median (range) serum PSA level in those with nodules was 2.0 (0.1–16.0) ng/ml and for those without nodules was 1.1 (0.1–8.0) ng/ml (p < 0.0001).

Conclusions

Serum PSA has a weak direct correlation with PV and not a reliable marker for the prediction of presence or absence of prostatic nodules in asymptomatic adult males.

Asian Race and Risk of Prostate Cancer: Results from the REDUCE Study

BACKGROUND

Global prostate cancer incidence rates are lower in Asian men than Caucasian men. Whether this is the result of less screening in Asian men remains to be determined. We examined whether Asian race was associated with prostate cancer diagnosis in the Reduction by Dutasteride of Cancer Events (REDUCE) study.

METHODS

REDUCE was a 4-year, multicenter, randomized trial of dutasteride versus placebo for prostate cancer prevention among men who underwent prostate-specific antigen (PSA)-independent biopsies at 2 and 4 years. Eligible men were ages 50 to 75 years, had PSA between 2.5 and 10 ng/mL, and a negative prestudy prostate biopsy. We tested the association between Asian and Caucasian race and prostate cancer diagnosis using logistic regression.

RESULTS

Of 8,122 men in REDUCE, 5,755 (71%) were Caucasian and 105 (1.8%) were Asian. Asians had lower body mass index (24.8 vs. 26.9 kg/m², P < 0.001), had smaller prostate volume (35.0 vs. 43.5 cc, P < 0.001), and were less likely to have abnormal digital rectal exams (P = 0.048), but were similar in baseline age, PSA, family history of prostate cancer, and smoking status compared with Caucasian men (all P ≥ 0.164). Asian men were equally likely to receive any on-study biopsy compared with Caucasian men (P = 0.634). After adjusting for potential confounders, Asian men were less likely to be diagnosed with prostate cancer during the 4-year study (OR = 0.49; 95% confidence interval, 0.28-0.88; P = 0.016), compared with Caucasian men.

CONCLUSIONS

In REDUCE, where all men underwent biopsies largely independent of PSA, Asian race was associated with lower prostate cancer diagnosis.

IMPACT

These findings suggest that lower prostate cancer risk in Asian men may be due to biological, genetic, and/or lifestyle factors.

Associations between sun sensitive pigmentary genes and serum prostate specific antigen levels

Background

Melanoma and prostate cancer may share risk factors. This study examined the association between serum PSA levels, which is a risk factor for prostate cancer, and variants in some melanoma-associated pigmentary genes.

Methods

We studied participants, all aged 70+ years, in the Concord Health and Ageing in Men Project who had no history of prostatitis or received treatment for prostate disease (n = 1033). We genotyped variants in MC1R (rs1805007, rs1805008), ASIP (rs4911414, rs1015362), SLC45A2 (rs28777, rs16891982), IRF4 (rs12203592), TYRP1 (rs1408799), TYR (rs1126809, rs1042602), SLC24A2 (rs12896399), and OCA2 (rs7495174). Generalised linear dominant models with Poisson distribution, log link functions and robust variance estimators estimated adjusted percentage differences (%PSA) in mean serum PSA levels (ng/mL) between variant and wildtype (0%PSA = reference) genotypes, adjusting for age, body mass index, serum 25OHD levels and birth regions (Australia or New Zealand (ANZ), Europe or elsewhere).

Results

Serum PSA levels were strongly associated with advancing age and birth regions: mean PSA levels were lower in Europe-born (-29.7%) and elsewhere-born (-11.7%) men than ANZ-born men (reference). Lower %PSA was observed in men with variants in SLC45A2: rs28777 (-19.6;95%CI: -33.5, -2.7), rs16891982 (-17.3;95%CI:-30.4,-1.7) than in wildtype men (reference). There were significant interactions between birth regions and PSA levels in men with variants in MC1R (rs1805007; p-interaction = 0.0001) and ASIP (rs4911414; p-interaction = 0.007). For these genes %PSA was greater in ANZ-born men and lower in Europe- and elsewhere-born men with the variant than it was in wildtype men. In a post hoc analysis, serum testosterone levels were increased in men with MC1R rs1805007 and serum dihydrotestosterone in men with ASIP rs1015362.

Conclusion

Men with SNPs in SLC45A2, who have less sun sensitive skin, have lower PSA levels. Men with SNPs in MC1R and ASIP, who have more sun sensitive skin, and were born in ANZ, have higher PSA levels. Androgens may modify these apparent associations of pigmentary genes and sun exposure with PSA levels.

Impact

PSA levels and possibly prostate cancer risk may vary with sun sensitivity and sun exposure, the effects of which might be modified by androgen levels.

A novel classification of prostate specific antigen (PSA) biosensors based on transducing elements

During the last few decades, there has been a tremendous rise in the number of research studies dedicated towards the development of diagnostic tools based on bio-sensing technology for the early detection of various diseases like cardiovascular diseases (CVD), many types of cancer, diabetes mellitus (DM) and many infectious diseases. Many breakthroughs have been developed in the areas of improving specificity, selectivity and repeatability of the biosensor devices. Innovations in the interdisciplinary areas like biotechnology, genetics, organic electronics and nanotechnology also had a great positive impact on the growth of bio-sensing technology. As a product of these improvements, fast and consistent sensing policies have been productively created for precise and ultrasensitive biomarker-based disease diagnostics. Prostate-specific antigen (PSA) is widely considered as an important biomarker used for diagnosing prostate cancer. There have been many publications based on various biosensors used for PSA detection, but a limited review was available for the classification of these biosensors used for the detection of PSA. This review highlights the various biosensors used for PSA detection and proposes a novel classification for PSA biosensors based on the transducer type used. We also highlight the advantages, disadvantages and limitations of each technique used for PSA biosensing which will make this article a complete reference tool for the future researches in PSA biosensing.

The age-specific reference intervals for tPSA, fPSA, and %fPSA in healthy Han ethnic male

INTRODUCTION

Prostate cancer (PC) is one of the most common malignancies in male, and has become the fastest growing malignancy in recent years. Prostate specific antigen (PSA) is widely used as a tumor marker to screen for PC. Many studies have been performed to define the reference intervals (RIs) for total circulating PSA (tPSA). The results were different among different nations and races, even in the same race. Few researches have been performed on the RIs of free PSA (fPSA) and the ratio of free to total PSA (%fPSA). In this study, we aimed to simultaneously determine the age-specific RIs for tPSA, fPSA, and %fPSA in the healthy Han ethnic male.

METHODS

A total of 1862 apparently healthy male aged from 21 to 94 years were included in our study. Nonparametric 95th percentile intervals were used to define the RIs.

RESULTS

The reference limits in different age groups (21-50, 51-60, 61-70, 71-80, and ≥81 years) were 2.07, 3.59, 4.93, 6.83, and 7.73 ng/mL for tPSA, and 0.60, 0.76, 0.83, 1.30, and 2.41 ng/mL for fPSA. The RIs of %fPSA were ≥0.16 for 21-50 years and ≥0.13 for male over 50 years old.

CONCLUSIONS

We established age-specific RIs for tPSA, fPSA and %fPSA. The newly established RIs should be more suitable for Chinese Han ethnic male. It will be valuable for physicians to make exact medical decision and appropriate medical intervention.

Relationship of age, prostate-specific antigen, and prostate volume in Indonesian men with benign prostatic hyperplasia

BACKGROUND

To investigate the relationship between age, prostate specific antigen (PSA), and prostate volume (PV) in Indonesian men with histologically proven benign prostatic hyperplasia.

METHODS

Data were generated from our BPH database from June 1994 until December 2013. Subjects were men with a minimum age of 40 years with chief complaint of LUTS or urinary retention, diagnosed with BPH. All patients underwent TRUS-guided prostate biopsy. Patients with PSA level >10 ng/mL were excluded from the study to exclude the possibility of occult prostate cancer. PV was measured with TRUS. Appropriate statistical tests were employed for data analysis.

RESULTS

In all, 1638 patients were enrolled in our study. There was a statistically significant difference in PSA (P = 0.03) and PV (P < 0.0001) between age groups. Overall correlation between age, PSA, and PV were: i). Age and PV (r = 0.12, P < 0.0001); ii). Age and PSA (r = 0.07, P = 0.008); iii). PSA and PV (r = 0.26, P < 0.0001). Subgroup analysis in terms of indwelling catheter use versus without: i). Age 66.09 ± 8 years versus 65.38 ± 7.66 years (P = 0.158); ii). PSA 4.93 ± 2.62 ng/mL versus 4.68 ± 2.82 ng/mL (P = 0.038); iii). PV 47.58 ± 21.33 mL versus 41.43 ± 20.55 mL (P < 0.0001). Correlation between age, PSA, and PV in patients were similar in patients with and without indwelling catheter.

CONCLUSION

In Indonesian men with biopsy-proven BPH, both PV and PSA increased with ageing. Prostate volume was significantly correlated with PSA. Even though the results were weaker, these results are consistent with results in other sets of population. The results vary between different countries and thus, ethnicities. Indonesia is a populous a sociocultural and ethnically diverse country. Therefore, aside from PSA, age, and PV, when investigating men with BPH, ethnicity may also need to be taken into account.

Prostate-specific antigen-based population screening for prostate cancer: current status in Japan and future perspective in Asia

In Western countries, clinical trials on prostate cancer screening demonstrated a limited benefit for patient survival. In the Asia-Pacific region, including Japan, the rate of prostate-specific antigen (PSA) testing remains very low compared with Western countries, and the benefits of population-based screening remain unclear. This review describes the current status of population screening and diagnosis for prostate cancer in Japan and discusses the efficacy of population screening for the Asian population. Since the 1990s, screening systems have been administered by each municipal government in Japan, and decreases in the prostate cancer mortality rate are expected in some regions where the exposure rate to PSA screening has increased markedly. A population-based screening cohort revealed that the proportion of metastatic disease in cancer detected by screening gradually decreased according to the increased exposure rate, and a decreasing trend in the proportion of cancer with high serum PSA levels after population screening was started. The prognosis of the prostate cancer detected by population screening was demonstrated to be more favorable than those diagnosed outside of the population screening. Recent results in screening cohorts demonstrated the efficacy of PSA. These recent evidences regarding population-based screening in Japan may contribute to establishing the optimal prostate cancer screening system in Asian individuals.

Decreasing trend in prostate cancer with high serum prostate-specific antigen levels detected at first prostate-specific antigen-based population screening in Japan

To clarify the recent trends in prostate-specific antigen (PSA) distribution in men in Japan, we analyzed the PSA distributions of men undergoing PSA-based population screening. We summarized the annual individual data of PSA-based population screening in Kanazawa, Japan, from 2000 to 2011, and analyzed baseline serum PSA values of the participants at the first population screening. Serum PSA distributions were estimated in all participants and those excluding prostate cancer patients according to age. From 2000 to 2011, 19 620 men participated aged 54–69 years old in this screening program. Mean baseline serum PSA level of all participants at the first screening was 2.64 ng ml⁻¹ in 2000, and gradually decreased to approximately 1.30 ng ml⁻¹ in 2006. That of participants excluding prostate cancer patients was 1.46 ng ml⁻¹ in 2000, and there was no remarkable change during the study period. The 95^th percentiles in the participants excluding prostate cancer patients detected at the first population screening of men aged 54–59, 60–64, and 65–69 years old were 2.90, 3.60, and 4.50 ng ml⁻¹, respectively. After the commencement of population screening, the proportion of prostate cancer patients with high serum PSA levels decreased. However, there were no changes in serum PSA levels in men without prostate cancer. Age-specific PSA reference level of men without prostate cancer in Japan was similar to that in China and Korea.

Prostate cancer screening in a healthy population cohort in eastern Nepal: an explanatory trial study

BACKGROUND

Prostate cancer features a substantial incidence and mortality burden, similarly to breast cancer, and it ranks among the top ten specific causes of death in males.

OBJECTIVE

To explore the situation of prostate cancer in a healthy population cohort in Eastern Nepal.

MATERIALS AND METHODS

This study was conducted in the Department of General Surgery at B. P. Koirala Institute of Health Sciences, Dharan, Nepal from July 2010 to June 2011. Males above 50 years visiting the Surgical Outpatient Department in BPKIHS were enrolled in the study and screening camps were organized in four Teaching District Hospitals of BPKIHS, all in Eastern Nepal. Digital rectal examination (DRE) was conducted by trained professionals after collecting blood for assessment of serum prostatic specific antigen (PSA). Trucut biopsies were performed for all individuals with abnormal PSA/DRE findings.

RESULTS

A total of 1,521 males more than 50 years of age were assessed and screened after meeting the inclusion criteria. The vast majority of individuals, 1,452 (96.2%), had PSA ≤4.0 ng/ml. Abnormal PSA (>4 ng/ml) was found in 58 (3.8%). Abnormal DRE was found in 26 (1.72%). DRE and PSA were both abnormal in 26 (1.72%) individuals. On the basis of raised PSA or abnormal DRE 58 (3.84%) individuals were subjected to digitally guided trucut biopsy. Biopsy report revealed benign prostatic hyperplasia in 47 (3.11%) and adenocarcinoma prostate in 11 (0.73%). The specificity of DRE was 66.0%with a sensitivity of 90.9% and a positive predictive value of 38.5%. The sensitivity of PSA more than 4ng/ml in detecting carcinoma prostate was 100% and the positive predictive value for serum PSA was 19.0%

CONCLUSIONS

The overall cancer detection rate in this study was 0.73% and those detected were locally advanced. Larger community-based studies are highly warranted specially among high-risk groups.

Ethnicity is an independent determinant of age-specific PSA level: findings from a multiethnic Asian setting

Objectives

To study the baseline PSA profile and determine the factors influencing the PSA levels within a multiethnic Asian setting.

Materials and Methods

We conducted a cross-sectional study of 1054 men with no clinical evidence of prostate cancer, prostate surgery or 5α-reductase inhibitor treatment of known prostate conditions. The serum PSA concentration of each subject was assayed. Potential factors associated with PSA level including age, ethnicity, height, weight, family history of prostate cancer, lower urinary tract voiding symptoms (LUTS), prostate volume and digital rectal examination (DRE) were evaluated using univariable and multivariable analysis.

Results

There were 38 men (3.6%) found to have a PSA level above 4 ng/ml and 1016 (96.4%) with a healthy PSA (≤4 ng/ml). The median PSA level of Malay, Chinese and Indian men was 1.00 ng/ml, 1.16 ng/ml and 0.83 ng/ml, respectively. Indians had a relatively lower median PSA level and prostate volume than Malays and Chinese, who shared a comparable median PSA value across all 10-years age groups. The PSA density was fairly similar amongst all ethnicities. Further analysis showed that ethnicity, weight and prostate volume were independent factors associated with age specific PSA level in the multivariable analysis (p<0.05).

Conclusion

These findings support the concept that the baseline PSA level varies between different ethnicities across all age groups. In addition to age and prostate volume, ethnicity may also need to be taken into account when investigating serum PSA concentrations in the multiethnic Asian population.

Contribution of genetic variation rs266882 to prostate-specific antigen levels in healthy controls with serum PSA below 2.0 ng/ml

We evaluated the impact of genetic variation in the prostate-specific antigen (PSA) gene (rs266882) on serum PSA levels in healthy men as well as risk factors for benign prostate hypertrophy (BPH) and prostate cancer. The study population comprised 91 men with PSA levels below 2.0 ng/ml as healthy controls, 78 men with PSA 2-10 ng/ml as a BPH group, and 128 prostate cancer patients, all in Korea. DNA was amplified by polymerase chain reaction and the product was sequenced. We found that PSA levels were associated with a G/A polymorphism only in healthy controls. The transition, however, was not associated with PSA levels of BPH and cancer patients, nor was it a risk factor. In conclusion, this genetic factor is important for determining serum PSA levels in the naive group, whereas the disruption of prostatic architecture in BPH or prostate cancer may be a major determining factor for PSA levels.

Racial and ethnic variation of PSA in global population: Age specific reference intervals for serum prostate specific antigen in healthy South Indian males

The serum PSA is universally accepted as the useful and clinically relevant tumor marker for monitoring therapy and identifying early recurrence in patients of carcinoma prostate throughout the world. However, application of serum PSA is limited to screening for early adenocarcinoma prostate among males above fifty years of age.Serum PSA concentration varies from one population to another in different parts of the world. Many groups of workers have selected 4 ng/ml of serum PSA as upper limit of normal range without giving due consideration for age specific increase in serum PSA. There is no single report available on normal decade wise age specific reference intervals for serum PSA in Indian males.The present study is undertaken to establish age specific reference intervals in healthy Indian males from 20-89 years belonging to subpopulation of Andhra Pradesh from South India. Our results revealed lowest concentration of 95 percentile serum PSA in Indian males compared to other populations globally. Contrary to this, healthy Afro Americans were found to have highest concentration of serum PSA compared to all other populations.

The Distribution of PSA Age-Specific Profiles in Healthy Irish Men between 20 and 70

Background. Ireland is estimated to have the highest European incidence rate of prostate cancer (Pca) in 2006 which will increase by 275% by 2025. This study aimed to determine PSA cutoff values in different age groups of healthy male patients without Pca. Methods. 660 men in a pilot men's health programme, aged 18–67, had PSA assayed. Men were grouped into 8 age groups at 5-year intervals: 30–34, 35–39, 40–44, 45–49, 50–54, 55–59, 60–64, and 64–70. Results. Linear regression demonstrates a PSA velocity of 0.024 ng/ml/year. The 95% confidence interval demonstrates a near flat line of PSA values from age 20 to 50 and rises after. When transformed logarithmically, PSA correlates highly with expected values from the normal distribution (0.98). A fractional polynomial quantile regression model was used to predict median and 95th percentile for PSA as follows: 30–34 (0.73, 1.57), 35–39 (0.71, 1.65), 40–44 (0.73, 1.85), 45–49 (0.78, 2.17), 50–54 (0.88, 2.63), 55–59 (1.01, 3.25), 60–64 (1.20, 4.02), and 64–70 (1.43, 4.96). Conclusions. PSA levels are similar to other racial groups but not as high as US Caucasians until 65 years. These data define the predicted PSA for the Irish population and provide a reference for future screening programmes.

Efficacy of Dose Escalation of Tamsulosin for the Treatment of Lower Urinary Tract Symptoms

OBJECTIVES

The aim of this study was to compare the efficacy of low (0.2 mg) and intermediate (0.4 mg) dose tamsulosin in treating lower urinary tract symptoms (LUTS).

METHODS

Patients were treated with low-dose tamsulosin for an initial run-in period of 12 weeks, then divided into two groups based on their clinical improvement. Patients were measured for objective parameters of peak flow rate and postvoid residual urine volume, as well as subjective symptom scores and perceived patient benefit of treatment. The items were then integrated as the LUTS Outcome Score to determine dose increase or maintenance. Overall outcome was determined at 36 weeks.

RESULTS

One hundred and seventy-four patients were enrolled and started on 0.2 mg tamsulosin treatment. One hundred and fifty-five patients completed the 36-week study. Sixty patients required dose increase to 0.4 mg at the 12th week. Baseline characteristics showed that a patient who would benefit from 0.4 mg dosage had higher age, daytime frequency, and lower peak urine flow rate. Patients receiving both 0.2 and 0.04 mg both showed improved clinical outcome measures. Higher improvement was found in voiding component symptom scores and urine flow rate improvement in patients receiving an increased dose.

CONCLUSION

Both low- and intermediate-dose tamsulosin are effective treatment regimens. Increasing from low to intermediate dose should follow assessment of both objective and subjective improvements.

Optimal baseline prostate-specific antigen level to distinguish risk of prostate cancer in healthy men between 40 and 69 years of age

The present study evaluated optimal baseline prostate-specific antigen (PSA) level at different ages in order to determine the risk of developing prostate cancer (CaP). We analyzed 6,651 Korean men, aged 40-69 yr. The serum PSA levels for these men were measured at one institute from 2000 to 2004 and were determined to be between 0-4 ng/mL. Patients were divided into 4 groups of 25th-percentile intervals, based on initial PSA level. Of these, the group with an increased risk was selected, and the optimal value was determined by the maximal area under a receiver-operating characteristic curve within the selected group. The risk of CaP diagnosis was evaluated by Cox regression. The mean follow-up period was 8.3 yr. CaP was detected in 27 of the 6,651 subjects. CaP detection rate was increased according to age. The optimal PSA value to distinguish the risk of CaP was 2.0 ng/mL for 50- to 69-yr-olds. Patients with a baseline PSA level greater than the optimal value had a 27.78 fold increase in the prostate cancer risk. Baseline PSA values are useful for determining the risk of developing CaP in Korean men for 50- and 69-yr-old. We suggest that PSA testing intervals be modified based on their baseline PSA levels.

The value of prostate-specific antigen in Asia

One of the most important diagnostic tools used to detect prostate cancer is prostate-specific antigen (PSA), yet increased PSA alone does not reflect the presence of prostate cancer. Other pathological prostatic conditions such as prostatitis and benign prostatic hyperplasia (BPH) may also increase the level of PSA. However, unlike in other prostate diseases, PSA has a key role in the diagnosis and management of prostate cancer. The incidence of prostate cancer varies from country to country, with the highest incidence being found in the Western world and the lowest in Asian countries. Owing to the low incidence of prostate cancer, there could be different views regarding the use of PSA in Asian countries, especially for the early detection/screening of prostate cancer. The purpose of this article is to review the use and value of PSA in the diagnosis of prostate diseases (especially prostate cancer) in Asian countries/populations. A literature search was performed in 'MEDLINE' (PubMed) and Google Scholar using main keywords such as 'PSA', 'PSA usage', 'PSA sensitivity and specificity', 'Asia', and various countries in Asia. Articles that provide population/community-based PSA data, together with the characteristics, distribution, and indications for PSA testing in the respective countries, were selected. Eleven papers were finally selected for inclusion in this review. Five studies found that PSA, by its 95th percentile value, have an age-referenced tendency in Asian males, similarly to the West. The predictive values of PSA in detecting prostate cancer are also quite similar to those in Western countries. With the exponential growth of the aging population in the world, especially in Asia, the incidence of prostate cancer will follow this upward trend. Therefore, PSA testing for screening or diagnostic purposes would increase with time in Asia.

Is it suitable to eliminate bone scan for prostate cancer patients with PSA ≤ 20 ng/mL?

PURPOSE

We evaluated the relationship between bone metastasis (BM) and clinical or pathological variables, including the serum prostate-specific antigen (PSA) concentration.

METHODS

This retrospective study included 579 consecutive patients with newly diagnosed prostate cancer (Pca) who underwent a bone scan study at our institution between 2002 and 2010. We used receiver operating characteristics curves to evaluate accuracy of bone metastasis between serum PSA 10 and 20 ng/mL.

RESULTS

A positive bone scan result was found in 83 men (14.3%) with PCa. However, 27 men (4.6%) with serum PSA between 10 and 20 ng/mL, 29/579 men (5.0%) with GS ≤ 7, and 21/83 (25.3%) with serum PSA ≤ 20 ng/mL and Gleason score (GS) ≤ 7 had positive bone scans. In the logistic regression analyses, clinical T stage (odds ratio [OR] = 3.26; 95% CI, 2.29-4.33; P = 0.021), GS (OR = 3.41; 95% CI, 2.91-4.63; P = 0.019), and serum PSA (OR = 8.37; 95% CI, 3.91-19.21; P < 0.001) were predictive factors of detecting the BM. When the serum PSA concentration ≤20 ng/mL and GS ≤ 7, AUC value of bone scans for the detection of BM was 0.640 (P = 0.020; 95% CI, 0.563-0.717). With serum PSA at 10 ng/mL and GS ≤ 7, the AUC values of bone scans were 0.828 (P < 0.001; 95% CI, 0.773-0.883).

CONCLUSIONS

Bone scans might be necessary in men with serum PSA between 10 and 20 ng/mL. New guidelines for eliminating bone scans in patients with newly diagnosed Pca are needed, especially in Asians.

Nomogram to predict insignificant prostate cancer at radical prostatectomy in Korean men: a multi-center study

PURPOSE

Due to the availability of serum prostate specific antigen (PSA) testing, the detection rate of insignificant prostate cancer (IPC) is increasing. To ensure better treatment decisions, we developed a nomogram to predict the probability of IPC.

MATERIALS AND METHODS

The study population consisted of 1,471 patients who were treated at multiple institutions by radical prostatectomy without neoadjuvant therapy from 1995 to 2008. We obtained nonrandom samples of n = 1,031 for nomogram development, leaving n = 440 for nomogram validation. IPC was defined as pathologic organ-confined disease and a tumor volume of 0.5 cc or less without Gleason grade 4 or 5. Multivariate logistic regression model (MLRM) coefficients were used to construct a nomogram to predict IPC from five variables, including serum prostate specific antigen, clinical stage, biopsy Gleason score, positive cores ratio and maximum % of tumor in any core. The performance characteristics were internally validated from 200 bootstrap resamples to reduce overfit bias. External validation was also performed in another cohort.

RESULTS

Overall, 67 (6.5%) patients had a so-called "insignificant" tumor in nomogram development cohort. PSA, clinical stage, biopsy Gleason score, positive core ratio and maximum % of biopsy tumor represented significant predictors of the presence of IPC. The resulting nomogram had excellent discrimination accuracy, with a bootstrapped concordance index of 0.827.

CONCLUSION

Our current nomogram provides sufficiently accurate information in clinical practice that may be useful to patients and clinicians when various treatment options for screen-detected prostate cancer are considered.

Preoperative nomograms for predicting extracapsular extension in Korean men with localized prostate cancer: a multi-institutional clinicopathologic study

We developed a nomogram to predict the probability of extracapsular extension (ECE) in localized prostate cancer and to determine when the neurovascular bundle (NVB) may be spared. Total 1,471 Korean men who underwent radical prostatectomy for prostate cancer between 1995 and 2008 were included. We drew nonrandom samples of 1,031 for nomogram development, leaving 440 samples for nomogram validation. With multivariate logistic regression analyses, we made a nomogram to predicts the ECE probability at radical prostatectomy. Receiver operating characteristic (ROC) analyses were also performed to assess the predictive value of each variable alone and in combination. The internal validation was performed from 200 bootstrap re-samples and the external validation was also performed from the another cohort. Overall, 314 patients (30.5%) had ECE. Age, Prostate specific antigen (PSA), biopsy Gleason score, positive core ratio, and maximum percentage of biopsy tumor were independent predictors of the presence of ECE (all P values <0.05). The nomogram predicted ECE with good discrimination (an area under the ROC curve of 0.777). Our nomogram allows for the preoperative identification of patients with an ECE and may prove useful in selecting patients to receive nerve sparing radical prostatectomy.

Age-specific PSA reference ranges in Chinese men without prostate cancer

This study is to determine age-specific prostate-specific antigen (PSA) distributions in Chinese men without prostate cancer (PC) and to recommend reference ranges for this population after comparison with other studies. From September 2003 to December 2006, 9 374 adult men aged from 18 to 96 years agreed to participate in the study. After all cases of PC were excluded, 8 422 adult men participated in statistical analysis and were divided into five age groups. Simple descriptive statistical analyses were carried out and quartiles and 95th percentiles were calculated for each age group. The age-specific PSA reference ranges are as follows: 40-49 years, 2.15 ng mL(-1); 50-59 years, 3.20 ng mL(-1); 60-69 years, 4.10 ng mL(-1); 70-79 years, 5.37 ng mL(-1). The results indicate that the ethnic differences in PSA levels are obvious. The currently adopted Oesterling's age-specific PSA reference ranges are not appropriate for Chinese men. The reference ranges of this study should be more suitable to Chinese men.

A comparison of prostate cancer detection rates by 12 or 6 core biopsy at different prostate-specific antigen densities in Korean men

OBJECTIVES

To evaluate the diagnostic value of 12 core biopsy versus sextant biopsy at different prostatic-specific antigen densities (PSAD).

METHODS

We retrospectively analyzed the records of 1,463 patients who underwent transrectal ultrasound-guided prostate biopsies at our institution. 995 patients underwent 12 core biopsy and 468 sextant biopsy of the prostate. The cancer detection rates achieved by these two methods were analyzed at different PSAD levels.

RESULTS

All patients were stratified into 5 groups according to PSAD level; group A: PSAD < 0.1 (n = 290), group B: 0.1 < or = PSAD < 0.2 (n = 572), group C: 0.2 < or = PSAD < 0.3 (n = 248), group D: 0.3 < or = PSAD < 0.4 (n = 122), and group E: PSAD > or = 0.4 (n = 231). In group B, 12 core biopsy had a higher detection rate than 6 core biopsy (P = 0.017).

CONCLUSIONS

These results demonstrate 12 core biopsy is better able to detect cancer than 6 core biopsy in patients with a PSAD in the range 0.1-0.2, which suggests that PSAD be considered when deciding on the number of prostate biopsy cores required.

Relationship between serum prostate-specific antigen levels and body mass index in healthy younger men

OBJECTIVES

To understand further the physiologic characteristics of serum prostate-specific antigen (PSA) concentrations in healthy younger men.

METHODS

A total of 2032 men, 20 to 39 years old, who visited our hospital for a routine health checkup were entered into the study. Pearson correlation coefficients were determined to evaluate the association between serum PSA and clinical parameters. Because of the log-normal distribution, the serum PSA levels were log-transformed for analysis.

RESULTS

Although the relationships were weak, significant negative correlations were noted between serum PSA and body weight (r = -0.107, P <0.001), body mass index (BMI; r = -0.131, P <0.001), aspartate aminotransferase (AST; r = -0.076, P = 0.001), alanine aminotransferase (ALT; r = -0.079, P = 0.001), gamma-glutamyltransferase (r = -0.046, P = 0.046), and creatinine clearance (r = -0.113, P <0.001). A positive correlation was found between serum PSA and creatinine (r = 0.053, P = 0.024). Age did not correlate with serum PSA level. The influence of clinical parameters on serum PSA was explored using multiple linear regression analysis. Using the stepwise method, all other explanatory variables, except BMI, AST, and creatinine were eliminated (log10[PSA] = -0.124[BMI] + 0.063[creatinine] - 0.053[AST] + 0.097; r = 0.152, P <0.001).

CONCLUSIONS

BMI, creatinine, and AST may influence the serum PSA level in this population. However, because it was not clear that this group should be considered at high risk of prostate cancer in the future, additional longitudinal research is needed.

Ethnic differences in distribution of serum prostate-specific antigen: a study in a healthy chinese male population

OBJECTIVES

To evaluate the normal distribution of serum prostate-specific antigen (PSA) levels in healthy Chinese men, because, until recently, studies conducted to establish normal serum PSA values have not involved a Chinese population.

METHODS

Between September 1999 and December 2001, 1096 healthy Chinese men aged 23 to 85 years, who had undergone a routine health examination, were recruited to this study. All underwent detailed clinical examinations, including serum PSA determination and digital rectal examination. All men with abnormal digital rectal examination findings and/or an abnormal serum PSA level (greater than 4.0 ng/mL) underwent transrectal ultrasound-guided sextant biopsy.

RESULTS

The median serum PSA concentration was 0.50 ng/mL (95th percentile 1.20) for men 23 to 29 years old (n = 77); 0.55 ng/mL (95th percentile 1.21) for men 30 to 39 years old (n = 189); 0.54 ng/mL (95th percentile 1.23) for men 40 to 49 years old (n = 233); 0.82 ng/mL (95th percentile 2.35) for men 50 to 59 years old (n = 177); 0.93 ng/mL (95th percentile 3.20) for men 60 to 69 years old (n = 265); and 1.17 ng/mL (95th percentile 3.39) for men 70 years old or older (n = 155). The serum PSA concentration correlated with age (P <0.001), with an increase of approximately 1.1% annually. No change occurred in the median serum PSA value and 95th percentile in men younger than 50 years old; a gradual increase was observed in men older than 50 years. In those 50 years old or older, the median and 95th percentile serum PSA values for Chinese men were significantly lower than those for other races and even for other Asian men.

CONCLUSIONS

These findings further confirm that the serum PSA level correlates with age. Moreover, the distribution and cutoff value of the serum PSA level differs along ethnic lines. In addition, our findings raise the question of whether lowering the PSA cutoff may enhance the detection of cancer in Chinese men who have the lowest prostate cancer rate.

Prognostic significance of the nadir prostate specific antigen level after hormone therapy for prostate cancer

PURPOSE

We determine whether the nadir prostate specific antigen (PSA) level after hormone therapy can be used to predict the progression to hormone refractory prostate cancer.

MATERIALS AND METHODS

We reviewed the progressive status and survival of 177 patients with stage C or D prostate cancer who had received hormone therapy at our institution. The overall survival rate, incidence of progression to hormone refractory prostate cancer and interval until progression were analyzed with reference to the nadir PSA level. Multiple regression analysis was used to analyze the predictive factors for progression to hormone refractory prostate cancer, and the relative efficacy of the nadir PSA level in predicting progression was evaluated by receiver operating characteristics analysis.

RESULTS

Median followup was 39 months (range 3 to 89) and 85.4% of patients (151) responded to treatment, of whom 77.5% (117) had progression to hormone refractory prostate cancer. Median time until nadir PSA levels were reached after hormone therapy was 8.1 months and median time until hormone refractory prostate cancer was 24.0 months. Nadir PSA levels were less than 0.2 ng./ml. in 31% of respondents, 0.2 to 1.0 ng./ml. in 23%, 1.1 to 10 ng./ml. in 42% and greater than 10 ng./ml. in 5%. These groups had similar clinicopathological characteristics. Nadir PSA levels correlated significantly with pretreatment PSA levels, Gleason scores and progression to hormone refractory prostate cancer (p = 0.01, p <0.01 and p <0.001, respectively), and inversely correlated with the interval to the establishment of hormone refractory prostate cancer (r = -0.465, p <0.05). By univariate analysis bone metastasis, nadir PSA, PSA at 6 months after treatment and pretreatment PSA were significantly associated with progression to hormone refractory prostate cancer. Only the nadir PSA was calculated to be an independent factor by multivariate analysis. Receiver operating characteristics analysis indicated that nadir PSA predicted progression to hormone refractory prostate cancer after 2 years with an accuracy of 86.2%. With the lower limit of the nadir PSA level set to 1.1 ng./ml., sensitivity was 80.3% and specificity was 83.8%, and these levels were deemed the most appropriate. Furthermore, nadir PSA after hormone therapy was an independent prognosticator for survival, as were initial levels of hemoglobin and alkaline phosphatase.

CONCLUSIONS

The nadir PSA level after hormone therapy may be the most accurate factor predicting the progression to hormone refractory prostate cancer and is an independent prognostic factor for survival. Furthermore, a lower limit for the nadir PSA level of 1.1 ng./ml. gives optimal sensitivity and specificity.

Distribution of serum prostate-specific antigen in healthy Korean men: influence of ethnicity

OBJECTIVES

To evaluate the normal distribution of serum prostate-specific antigen (PSA) levels in healthy Korean men. The subjects included men younger than 40 years of age, because information on serum PSA levels in younger men is scarce.

METHODS

Between January 1997 and December 1998, the serum PSA levels of the subjects who visited our hospital for a routine health checkup were determined. All men who were older than 50 years with abnormal digital rectal examination findings and/or an abnormal serum PSA level (greater than 4.0 ng/mL) underwent transrectal ultrasound-guided sextant biopsy. Two men who were found to have cancer were excluded from the analysis. The detection rate of prostate cancer for men with abnormal digital rectal examination findings and/or an abnormal serum PSA level was 2.0% for men 50 to 59 years old; 0.0% for men 60 to 69 years old; and 11.1% for men 70 to 79 years old. A total of 8297 men (aged 20 to 79 years) were included in the study.

RESULTS

The median serum PSA level (5th to 95th percentile range) was 0.90 ng/mL (0.33 to 2.25) for men 20 to 29 years old; 0.89 ng/mL (0.30 to 2.35) for men 30 to 39 years old; 0.89 ng/mL (0.30 to 2.36) for men 40 to 49 years old; 0.96 ng/mL (0.32 to 2.96) for men 50 to 59 years old; 1.22 ng/mL (0.33 to 3.78) for men 60 to 69 years old; and 1.25 ng/mL (0.30 to 7.49) for men 70 to 79 years old. The median and 95th percentile serum PSA levels of Korean men younger than 50 years were higher, but those for men 50 years old or older were lower than in other races. In our study cohort, the serum PSA level weakly correlated with age (r = 0.088, P <0.001). The serum PSA level weakly correlated with age in men 50 years old or older (r = 0.116, P <0.001) but in men younger than 50 years, it did not correlate (r = 0.000, P = 0.987).

CONCLUSIONS

These results suggest that the distribution and cutoff value of the serum PSA level in Korean men differ from those in other races. In addition, our findings raise the question of whether lowering the PSA cutoff may enhance the detection of cancer in this population with low prostate cancer rates.