The prostate specific antigen era in the United States is over for prostate cancer: what happened in the last 20 years?

[PSA--Quo vadis?]

Prostate cancer is the most frequent cancer in males. Because of the high cure rates, early detection of prostate cancer should identify organ-confined prostate cancers. An early detection examination should be performed annually starting at the age of 50 years and ending when life expectancy is less than 10 years. Digital rectal examination is supplemented by determination of prostate-specific antigen (PSA). Before the first PSA test, the patient must be informed of possible consequences such as biopsy recommendation and treatment options. A threshold of 4 ng/ml is defined as the indication for prostate biopsy. Imaging methods do not play a major role in early detection of prostate cancer today. Early detection identifies many latent prostate cancers, and patients may receive overtreatment. A possible solution is to change the early detection paradigm from detection of all prostate cancers to identification of aggressive ones. In this article, early detection is discussed based on the recent literature.

Techniques and predictive models to improve prostate cancer detection

The use of prostate-specific antigen (PSA) as a screening test remains controversial. There have been several attempts to refine PSA measurements to improve its predictive value. These modifications, including PSA density, PSA kinetics, and the measurement of PSA isoforms, have met with limited success. Therefore, complex statistical and computational models have been created to assess an individual's risk of prostate cancer more accurately. In this review, the authors examined the methods used to modify PSA as well as various predictive models used in prostate cancer detection. They described the mathematical underpinnings of these techniques along with their intrinsic strengths and weaknesses, and they assessed the accuracy of these methods, which have been shown to be better than physicians' judgment at predicting a man's risk of cancer. Without understanding the design and limitations of these methods, they can be applied inappropriately, leading to incorrect conclusions. These models are important components in counseling patients on their risk of prostate cancer and also help in the design of clinical trials by stratifying patients into different risk categories. Thus, it is incumbent on both clinicians and researchers to become familiar with these tools. Cancer 2009;115(13 suppl):3085-99. (c) 2009 American Cancer Society.

Dynamic contrast-enhanced MR imaging in the evaluation of patients with prostate cancer

Prostate cancer is a common tumor among men, with increasing diagnosis at an earlier stage and a lower volume of disease because of screening with prostate-specific antigen (PSA). The need for imaging of the prostate stems from a desire to optimize treatment strategy on a patient and tumor-specific level. The major goals of prostate imaging are (1) staging of known cancer, (2) determination of tumor aggressiveness, (3) diagnosis of cancer in patients who have elevated PSA but a negative biopsy, (4) treatment planning, and (5) the evaluation of therapy response. This article concentrates on the role of dynamic contrast-enhanced MR imaging in the evaluation of patients who have prostate cancer and how it might be used to help achieve the above goals. Various dynamic contrast enhancement approaches (quantitative/semiquantitative/qualitative, high temporal versus high spatial resolution) are summarized with reference to the relevant strengths and compromises of each approach.

Beyond PSA: utility of novel tumor markers in the setting of elevated PSA

The introduction of prostate-specific antigen (PSA) for prostate cancer screening and detection has been used for over 20 years and has dramatically changed the face of prostate cancer. Although it is a highly sensitive serum test, its routine use has been the subject of continued controversy owing to its limited specificity. Due to this lack of specificity, many have proposed modifications of PSA in an attempt to bolster the performance of this analyte. The human genome project and high throughput gene expression profiling has recently yielded several promising molecular biomarkers for prostate cancer detection beyond PSA or PSA modifications. This review will first highlight several characteristics of an ideal biomarker, then focus on select emerging biomarkers for the detection of prostate cancer.

Molecular biomarkers in prostate cancer

BACKGROUND

After more than two decades of clinical use, serum prostate-specific antigen (PSA) has increased the early diagnosis of prostate cancer, detecting the disease even when small volumes are present. Although stage migration of prostate cancer has occurred, PSA has well-known limitations, despite attempts at refinement and modification, such as the use of PSA velocity, which have been used to improve it. New biomarkers for prostate cancer have been discovered, with promising early results.

OBJECTIVE/METHODS

This article reviews the ubiquitous current literature on biomarkers in prostate cancer. A search using MEDLINE and EMBASE databases was performed and those articles reporting biomarkers in prostate cancer with clinically significant findings in terms of detection were analyzed. Immunohistochemical markers were not considered for this review.

RESULTS/CONCLUSION

Despite many markers being promising, no single marker has satisfied the criteria as a perfect candidate. Limited clinical use of IL-6, TGF-β1 and PCA3 has commenced, and further widespread availability of these tests is expected in the coming years. The future lies in artificial neural networks and panels of markers instead of individual assays. Although PSA has some well-known limitations, it is at present the best marker available for prostate cancer when used in conjunction with nomograms or risk calculators.

Benign prostatic hyperplasia-associated free prostate-specific antigen improves detection of prostate cancer in an artificial neural network

OBJECTIVES

To show discriminative power between patients with prostate cancer (PCa) and those with "no evidence of malignancy" using "benign" prostate-specific antigen (bPSA) and the new automated Access benign prostatic hyperplasia-associated (BPHA) research assay within a percent free PSA (%fPSA)-based artificial neural network (ANN) model.

METHODS

The sera from 287 patients with PCa and 254 patients with no evidence of malignancy were measured using the BPHA, total PSA (tPSA), and fPSA assays with Access immunoassay technology, with a 0-10 ng/mL tPSA range. Two ANN models with Bayesian regularization and leave-one-out validation using the 4 input parameters of tPSA, %fPSA, age, and prostate volume and 1 containing BPHA/tPSA were constructed and compared by receiver operating characteristic curve analysis.

RESULTS

The BPHA/tPSA-based ANN reached the significant greatest area under the receiver operating characteristic curve (AUC 0.81; P = .0004 and P = .0024) and best specificity (53.9% and 44.5%) compared with the ANN without BPHA/tPSA (AUC 0.77; specificity 50% and 40.6%) and %fPSA (AUC 0.77; specificity 40.9% and 27.2%) at 90% and 95% sensitivity, respectively. The AUCs for tPSA (0.58), BPHA (0.55), BPHA/fPSA (0.51), prostate volume (0.69), and BPHA/tPSA (0.69) were significantly lower.

CONCLUSIONS

Although BPHA as single marker or ratio to tPSA did not improve the diagnostic performance of %fPSA or tPSA, the incorporation of BPHA/tPSA into an ANN model increased the specificity compared with %fPSA by 13% and 17% at 90% and 95% sensitivity, respectively. Thus, the automated BPHA research assay might improve PCa detection when incorporating this new marker into an ANN.

Urinary protein biomarkers of cancer

BACKGROUND

Although several cancer biomarkers are now in use, few have the necessary sensitivity and specificity to eliminate the need for invasive diagnostic procedures. With the expansion of proteomics, new technologies have been used to study various cancers, resulting in the discovery of several potential urine biomarkers. Urine is an ideal medium for the detection of biomarkers because of the non-invasive means of collecting samples and demonstrated shedding of cells, proteins, enzymes, nucleic acids and metabolic products into urine during various pathological processes.

OBJECTIVE

To review the contemporary literature regarding urinary protein markers of cancer.

METHODS

A PubMed search for 'urinary protein biomarkers of cancer' revealed 4679 scientific publications. The search was limited to studies published over the last 5 years and reviewed pertinent findings regarding biomarker evaluation and discovery.

RESULTS

Several urinary protein biomarkers have been described for urologic, gynecologic, gastrointestinal and neurologic tumors. Some have been selected for use in clinical practice, whereas others have been abandoned owing to inconclusive follow-up studies.

CONCLUSION

Several potential urinary protein markers for cancer exist, yet multi-institutional, prospective trials are needed to validate results before implementation in clinical scenarios.

The relation of alpha-linolenic acid to the risk of prostate cancer: a systematic review and meta-analysis

BACKGROUND

alpha-Linolenic acid (ALA; 18:3n-3) has been associated inconsistently with an increased risk of prostate cancer. Additional studies have become available since the publication of 2 previous meta-analyses.

OBJECTIVE

The objective was to review the published data on the relation between ALA and prostate cancer.

DESIGN

We conducted a systematic review to identify studies that included data on ALA and risk of prostate cancer. Data were pooled from studies that compared the highest ALA quantile with the lowest ALA quantile, and risk estimates were combined by using a random-effects model.

RESULTS

The relation between ALA and prostate cancer is inconsistent across studies. We pooled data from 8 case-control and 8 prospective studies. The summary estimate revealed that high ALA dietary intakes or tissue concentrations are weakly associated with prostate cancer risk (relative risk [RR]: 1.20; 95% CI: 1.01, 1.43). When examined by study type (ie, retrospective compared with prospective or dietary ALA compared with tissue concentration) or by decade of publication, only the 6 studies examining blood or tissue ALA concentrations revealed a statistically significant association. With the exception of these studies, there was significant heterogeneity and evidence of publication bias. After adjustment for publication bias, there was no association between ALA and prostate cancer (RR: 0.96; 95% CI: 0.79, 1.17).

CONCLUSIONS

Studies examining the relation between ALA and prostate cancer have produced inconsistent findings. High ALA intakes or high blood and adipose tissue concentrations of ALA may be associated with a small increased risk of prostate cancer. However, these conclusions are qualified because of the heterogeneity across studies and the likelihood of publication bias.

Serum CXCL13 positively correlates with prostatic disease, prostate-specific antigen and mediates prostate cancer cell invasion, integrin clustering and cell adhesion

Chemokines and their corresponding receptor interactions have been shown to be involved in prostate cancer (PCa) progression and organ-specific metastasis. We have recently shown that PCa cell lines and primary prostate tumors express CXCR5, which correlates with PCa grade. In this study, we present the first evidence that CXCL13, the only ligand for CXCR5, and IL-6 were significantly elevated in PCa patient serum compared to serum from subjects with benign prostatic hyperplasia (BPH), or high-grade prostatic intraepithelial neoplasia (HGPIN) as well as normal healthy donors (NHD). Serum CXCL13 levels significantly (p<0.0001) correlated with serum prostate-specific antigen (PSA), whereas serum IL-6 levels significantly (p<0.0003) correlated with CXCL13 serum levels. CXCL13 was found to be a better predictor of PCa than PSA. CXCL13 was highly expressed by human bone marrow endothelial (HBME) cells and osteoblasts (OBs), but not osteoclasts (OCs), following treatment with physiologically relevant levels of interleukin-6 (IL-6). We further demonstrate that CXCL13, produced by IL-6-treated HBME cells, was able to induce PCa cell invasion in a CXCR5-dependent manner. CXCL13-mediated PCa cell adhesion to HBME cells and alpha(v)beta(3)-integrin clustering was abrogated by CXCR5 blockade. These results demonstrate that the CXCL13-CXCR5 axis is significantly associated with PCa progression.

A duplex quantitative polymerase chain reaction assay based on quantification of alpha-methylacyl-CoA racemase transcripts and prostate cancer antigen 3 in urine sediments improved diagnostic accuracy for prostate cancer

PURPOSE

Most men with increased serum prostate specific antigen and negative biopsy require repeat biopsy because of the lack of a sensitive and specific prostate cancer detection test. In this study we evaluated the diagnostic potential of a duplex assay for prostate cancer by quantifying transcript levels of alpha-methylacyl-CoA racemase and prostate cancer antigen 3 in urine sediments following prostatic massage.

MATERIALS AND METHODS

Urine sediments from 92 patients, 43 with and 49 without prostate cancer, were collected after digital rectal examination. Transcript levels of AMACR, PCA3 and PSA in total RNA isolated from these samples were determined by absolute quantitative real-time polymerase chain reaction. AMACR and PCA3 scores were obtained by normalizing the transcript level to that of prostate specific antigen for each sample and multiplying by 100.

RESULTS

AMACR (p = 0.006) and PCA3 (p = 0.014) scores, but not serum prostate specific antigen (p = 0.306), distinguished specimens from patients with prostate cancer from specimens from patients without prostate cancer, and ROC analysis established the diagnostic cutoff scores for the AMACR and PCA3 tests at 10.7 and 19.9, respectively. As determined from these cutoff scores the AMACR test had 70% (95% CI 56-83) sensitivity and 71% (95% CI 59-84) specificity, whereas the PCA3 test had 72% (95% CI 59-85) sensitivity and 59% (95% CI 45-73) specificity for prostate cancer detection. The combined use of AMACR and PCA3 scores in a dual marker test increased sensitivity to 81% (95% CI 70-93) and specificity to 84% (95% CI 73-94).

CONCLUSIONS

Urinary AMACR and PCA3 tests were superior to a serum prostate specific antigen test for detecting prostate cancer. Their combined use in a dual marker test further improved sensitivity and accuracy, and could serve as a surveillance test after repeat negative prostate biopsies.

The routine use of prostate-specific antigen for early detection of cancer prostate in India: Is it justified?

BACKGROUND

The use of prostate-specific antigen (PSA) for early detection of prostate cancer is a widely debated issue. The average Indian urologist is faced with the dilemma of whether PSA testing should be routinely offered to men over 50 years of age. The Urological Society of India is yet to issue any guidelines on PSA testing. This article attempts to explore scientific evidence dealing with this controversial subject.

MATERIALS AND METHODS

A MEDLINE search was performed using the words 'PSA screening', 'prostate cancer statistics', and 'PSA screening guidelines'. The relevant articles were then analysed for evidence regarding the utility of PSA screening.

RESULTS

Prostate cancer does not qualify to be categorized as a major health problem in India. The natural history of screen-detected cancer is not known. Prostate-specific antigen testing for early detection of prostate cancer has questionable benefits and has a potential to cause harm to asymptomatic individuals. There is no consensus amongst learned medical societies as to what should be the best approach for PSA testing. Most organizations caution against widespread PSA screening and emphasize on informed consent and patient counseling with regard to PSA testing. Randomized prospective trials are ongoing to assess to the true impact of screening on prostate cancer mortality.

CONCLUSIONS

There is no scientific rationale to advocate routine use of PSA for early detection of prostate cancer in Indian males. Results of randomized screening trials are awaited to clarify on this issue.

Dynamic contrast-enhanced magnetic resonance imaging in prostate cancer

Prostate cancer remains a major health concern for the male population. During the past decade, a dramatic increase in prostate-specific antigen and transurethral resection of the prostate has resulted in increased detection rate of small lesions and increased incidence of this disease. Needle biopsies in asymptomatic men have also contributed to the increased incidence of prostate cancer, leading to an increasing incidence-to-mortality ratio. Magnetic resonance imaging (MRI) is the modality of choice in prostate cancer patients with increased prostate-specific antigen levels before or after prostate cancer diagnosis confirmed by biopsy and T2-weighted imaging (T2W) has been used as a standard technique in detection. During the last decade, dynamic contrast-enhanced MRI has emerged as one of the main techniques used in multiparametric MRI of the prostate gland in cancer patients. Dynamic contrast-enhanced MRI has been routinely used for detection and diagnosis of the tumor, for staging and monitoring the therapeutic response, as well as for guiding targeted biopsies in patients with suspected prostate cancer or with a negative biopsy result. In this article, we are going to review the analysis techniques of dynamic contrast-enhanced MRI and its various clinical applications in prostate cancer patients.

Vibrational spectroscopy: a clinical tool for cancer diagnostics

Vibrational spectroscopy techniques have demonstrated potential to provide non-destructive, rapid, clinically relevant diagnostic information. Early detection is the most important factor in the prevention of cancer. Raman and infrared spectroscopy enable the biochemical signatures from biological tissues to be extracted and analysed. In conjunction with advanced chemometrics such measurements can contribute to the diagnostic assessment of biological material. This paper also illustrates the complementary advantage of using Raman and FTIR spectroscopy technologies together. Clinical requirements are increasingly met by technological developments which show promise to become a clinical reality. This review summarises recent advances in vibrational spectroscopy and their impact on the diagnosis of cancer.

Evaluating localized prostate cancer and identifying candidates for focal therapy

Can focal therapy successfully control prostate cancer? Also, if so, which patients should be considered eligible? With limited data available from relatively few patients, these questions are difficult to answer. At this writing, the most likely candidates for focal therapy are patients with low-risk, small-volume tumors, located in 1 region or sector of the prostate, who would benefit from early intervention. The difficulty lies in reliably identifying these men. The larger number of cores obtained in each needle biopsy session has increased both the detection of prostate cancer and the potential risk of overtreating many patients whose cancers pose very little risk to life or health. Urologists typically perform at least a 12-core template biopsy. Although the debate continues about the optimal template, laterally and peripherally directed biopsies have been shown to improve the diagnostic yield. However, as many as 25% of tumors arise anteriorly and can be missed with peripherally directed techniques. Prostate cancer tends to be multifocal, even in its earliest stages. However, the secondary cancers are usually smaller and less aggressive than the index cancer. They appear similar to the incidental cancers found in cystoprostatectomy specimens and appear to have little effect on prognosis in surgical series. When a single focus of cancer is found in 1 core, physicians rightly suspect that more foci of cancer are present in the prostate. Assessing the risk in these patients is challenging when determined by the biopsy data alone. To predict the presence of a very low-risk or "indolent" cancer, nomograms have been developed to incorporate clinical stage, Gleason grade, prostate-specific antigen levels, and prostate volume, along with the quantitative analysis of the biopsy results. Transperineal "mapping" or "saturation" biopsies have been advocated to detect cancers missed or underestimated by previous transrectal biopsies. This approach could provide the accurate staging, grading, and tumor localization needed for a focal therapy program. Nevertheless, for men with minimal cancer who are amenable to active surveillance or focal therapy, consensus about the most accurate biopsy strategy has not yet been reached. Imaging, particularly magnetic resonance imaging and magnetic resonance spectroscopic imaging, has been used to assess men with early-stage prostate cancer. Large-volume cancers can be seen reasonably well, but small lesions have been difficult to detect reliably or measure accurately. Factors such as voxel resolution, organ movement, biopsy artifact, and benign changes have limited the consistent estimation of the quantitative tumor volume. Nevertheless, magnetic resonance imaging and magnetic resonance spectroscopic imaging can aid in evaluating patients with prostate cancer being considered for focal therapy by providing additional evidence that the patient does not harbor an otherwise undetected high-risk, aggressive cancer. In some cases, imaging can usefully identify the location of even a limited-sized index cancer. When imaging findings are substantiated by mapping biopsy results, confidence in the accurate characterization of the cancer is enhanced. Correlating the imaging results with tissue changes during and after treatment can be of use in monitoring the ablative effects in the prostate and in assessing for tumor recurrence. More work is necessary before staging studies can uniformly characterize a prostate cancer before therapy, much less reliably identify and locate small-volume cancer within the prostate. However, exploring the role of focal ablation as a therapeutic option for selected men with low-risk, clinically localized, prostate cancer need not await the emergence of perfectly accurate staging studies, any more than the application of radical surgery or radiotherapy have. Modern biopsy strategies, combined with optimal imaging and nomograms to estimate the pathologic stage and risk, taken together, provide a sound basis for the selection of appropriate patients for entry into prospective clinical trials of focal therapy.

Biochemical recurrence after radical prostatectomy for prevalent versus incident cases of prostate cancer : implications for management

BACKGROUND

Among screened populations, it is unknown whether men with prostate cancer (PC) diagnosed at the initial screening (prevalent cases) have a different outcome than men who are diagnosed at subsequent screenings (incident cases) after adjusting for known prognostic factors.

METHODS

The current study cohort was comprised of 1923 men from a prospective PC screening study who underwent radical prostatectomy (RP) between September 19, 1989 and May 22, 2002. Cox regression multivariate analysis was used to determine whether having prevalent PC versus incident PC was associated with the time to prostate-specific antigen (PSA) failure after RP after adjusting for PSA level, Gleason score, clinical tumor (T) classification, and year of RP.

RESULTS

Men with prevalent PC had higher PSA levels (P < .001) and more advanced clinical T classification (P < .001) than men with incident PC. After a median follow-up of 6.1 years, factors that were associated with a significantly shorter time to PSA failure after RP were prevalent PC (adjusted hazard ratio [AHR], 1.8; 95% confidence interval [95% CI], 1.3-2.6; P = .0005), baseline PSA (AHR, 1.07; 95%CI, 1.04-1.09; P < .001), Gleason 7 disease (AHR, 2.5; 95% CI, 1.9-3.3; P < .001), Gleason 8 to 10 disease (AHR, 2.3; 95%CI, 1.5-3.5; P < .001), and the year of RP (AHR, 0.92; 95%CI, 0.86-0.97; P = .003). Men with prevalent PC also had worse outcomes after adjusting for their more advanced pathologic features.

CONCLUSIONS

After adjusting for known prognostic factors, men with prevalent PC had a poorer outcome after RP than men with incident PC. The authors believe that this finding should be taken into consideration when weighing the risk of recurrence and treatment options for men who are diagnosed with PC on their initial screening.

Percentage of tumor in prostatectomy specimens: a study of American Veterans

In this study, I have estimated the percentage of tumor by visual estimate in 447 prostatectomy specimens from American Veterans Affairs patients and related this measurement to overall survival. Although percentage of tumor was significantly related to the serum prostate-specific antigen level, tumor stage, and Gleason score-that is, it was not statistically independent from these-it was more closely associated with overall survival than any of them. Altogether, 2 variables available at the time of the prostatectomy related to survival: patient age (P = .0032; Cox proportional hazards model analysis) and percentage of tumor (P = .0013; Cox model). Patient age undoubtedly reflects the combination of comorbidities and general expected length of life. Percentage of tumor, by contrast, seems to efficiently reflect any undue hazard for early death due to prostate cancer. The results suggest that percentage of tumor is a useful prognostic variable for understanding risk of early death after prostatectomy.

Prostate cancer--to screen, or not to screen, is that the question?

There continues to be controversy regarding serum Prostate-Specific Antigen (PSA) and prostate cancer screening. We anxiously await the results of two large prospective randomized clinical trials (Prostate, Lung, Colon, and Ovary-PCLO screening trial in the US and European Randomized Study of Screening for Prostate Cancer-ERSPC in Europe) assessing the benefits of prostate cancer screening. However the true question to answer may be which cancer to treat and when should we treat it.

Saturation biopsy improves preoperative Gleason scoring of prostate cancer

We evaluated the differences between conventional needle biopsy (CB) and saturation biopsy (SB) techniques with regard to the prediction of Gleason score, tumor stage, and insignificant prostate cancer. Data from a total number of 240 patients were analyzed. The main group, consisting of 185 patients, was diagnosed according to a saturation prostate needle biopsy protocol (SB), by which more than 12 cores were taken per biopsy. The control group was diagnosed using CB, by which 12 or less than 12 cores were taken per biopsy (n=55). In the main group, the Gleason score of the biopsy was confirmed in 19.5%, in the control group in 23.5% according to the prostatectomy specimen (p=0.50). Upgrading after the operation was found in 56.7% in the main group and in 60% in the control group (p=0.24). Downgrading after the operation was found in 23.9% in the main group and in 16.3% in the control group (p=0.24). If the Gleason score of the postoperative specimens differed by only one point from the biopsy, we considered this a minor deviation. In the main group, 59% of the carcinomas were preoperatively classified correctly or revealed minor deviation in Gleason scores. In contrast, only 47% of the carcinomas in the control group were assessed correctly or with minor deviation in Gleason scores. Thus, the main group demonstrated a better rate of preoperative prediction in tumor grading assessed by Gleason score (p=0.05). In addition, the Gleason scores of both protocols were assigned to three groups (Gleason <7; Gleason 7; Gleason >7), and the group changes from the biopsy to the prostatectomy specimen were found to be significantly more frequent in the CB group (p=0.04). There was no significant difference between the two types of biopsy techniques regarding tumor stage or the detection of insignificant carcinomas. The advantage of the extensive prostate needle biopsy technique (SB) is a better preoperative prediction of the Gleason score as well as the risk groups with Gleason scores <7, equal to 7, or >7. Both techniques fail to detect insignificant prostate cancer.

National Academy of Clinical Biochemistry Laboratory Medicine Practice Guidelines for Use of Tumor Markers in Testicular, Prostate, Colorectal, Breast, and Ovarian Cancers

Background: Updated National Academy of Clinical Biochemistry (NACB) Laboratory Medicine Practice Guidelines for the use of tumor markers in the clinic have been developed.

Methods: Published reports relevant to use of tumor markers for 5 cancer sites—testicular, prostate, colorectal, breast, and ovarian—were critically reviewed.

Results: For testicular cancer, α-fetoprotein, human chorionic gonadotropin, and lactate dehydrogenase are recommended for diagnosis/case finding, staging, prognosis determination, recurrence detection, and therapy monitoring. α-Fetoprotein is also recommended for differential diagnosis of nonseminomatous and seminomatous germ cell tumors. Prostate-specific antigen (PSA) is not recommended for prostate cancer screening, but may be used for detecting disease recurrence and monitoring therapy. Free PSA measurement data are useful for distinguishing malignant from benign prostatic disease when total PSA is &lt;10 μg/L. In colorectal cancer, carcinoembryonic antigen is recommended (with some caveats) for prognosis determination, postoperative surveillance, and therapy monitoring in advanced disease. Fecal occult blood testing may be used for screening asymptomatic adults 50 years or older. For breast cancer, estrogen and progesterone receptors are mandatory for predicting response to hormone therapy, human epidermal growth factor receptor-2 measurement is mandatory for predicting response to trastuzumab, and urokinase plasminogen activator/plasminogen activator inhibitor 1 may be used for determining prognosis in lymph node–negative patients. CA15-3/BR27–29 or carcinoembryonic antigen may be used for therapy monitoring in advanced disease. CA125 is recommended (with transvaginal ultrasound) for early detection of ovarian cancer in women at high risk for this disease. CA125 is also recommended for differential diagnosis of suspicious pelvic masses in postmenopausal women, as well as for detection of recurrence, monitoring of therapy, and determination of prognosis in women with ovarian cancer.

Conclusions: Implementation of these recommendations should encourage optimal use of tumor markers.

Diagnostic strategies and the incidence of prostate cancer: reasons for the low reported incidence of prostate cancer in China

We have analysed the reasons for the low reported incidence of prostate cancer in China and argue for early diagnosis and treatment of this disease. According to the 2002 database of the International Agency for Research on Cancer (IARC), the age-standardized incidence of prostate cancer in China is 1.6/10(5) person years (PY), with a mortality rate of 1.0/10(5) PY and mortality-to-incidence rate ratio (MR/IR) = 0.63. The MR/IR ratio of prostate cancer in China was found to be higher than the average in Asia (MR/IR = 0.57) and much higher than that in North America (MR/IR = 0.13). These data indicate that in China most prostate cancers were in the advanced stages at the time of diagnosis, and that patients had a short survival time thereafter. In 2004, Stamey et al. reported a retrospective American study of prostate cancer for the years 1983-2003. It was shown that most cases of prostate cancer detected by prostate-specific antigen (PSA) screening were in the advanced stage at the start of this 20-year period. These early follow-up data are quite similar to the results obtained from mass PSA screening of elderly men in Changchun, China. However, after the American programmes for early diagnosis and treatment of prostate cancer were accepted, tumours were diagnosed at earlier stages. On the basis of these findings, mass screening should be performed in the whole of China using serum PSA to facilitate early diagnosis and treatment of prostate cancer.

Correlation between prostate needle biopsies and radical prostatectomy specimens: can we predict pathological outcome?

AIMS

Prostate needle biopsy findings provide important information when considering treatment options. We examine the correlation between needle biopsy and radical prostatectomy pathology to predict patients at high risk of harbouring adverse pathological findings.

METHODS

We reviewed data from 100 consecutive patients who underwent radical prostatectomy between 1 January 2003 and 31 January 2005 at the Singapore General Hospital. Pre-operative clinical findings and needle biopsy pathological data were prospectively collected and compared with the final histology.

RESULTS

The mean pre-biopsy PSA level was 9.4 +/- 5.1 microg/L. Median maximum percent of tumour in any core was 50% (range 5-100) and mean percentage of positive cores was 34.5 +/- 23%. There was under-grading of the final tumour score in 27 (27%) patients on biopsy as compared with the radical prostatectomy, while over-grading occurred in eight (8%) patients. On stratifying patients pre-operatively into low risk and high risk groups, patients in the high risk group had a significantly higher chance of having adverse radical prostatectomy histology such as extraprostatic extension, positive surgical margins or tumour volume >3.0 mL (p = 0.041, OR = 3.96, 95%CI 1.13-13.86).

CONCLUSIONS

Our results demonstrated good pathological correlation between prostate needle biopsies and their radical prostatectomies. Patients with Gleason scores of 7 or more, maximum percent of tumour in any core >50%, or percent of positive cores of >50% on needle biopsy had a higher risk of having adverse pathological findings at radical prostatectomy. The converse, however, is not necessarily true, as a result of sampling error during the biopsy.

Annexin A3 in urine: a highly specific noninvasive marker for prostate cancer early detection

PURPOSE

In prostate cancer cases the early diagnosis of tumors carrying a high risk of progression is of the utmost importance. There is an urgent clinical need to avoid unnecessary biopsies and subsequent overtreatment. We validated annexin A3 as a diagnostic marker for prostatic disease in typical clinical populations and relevant segments, such as patients with a negative digital rectal examination and low prostate specific antigen.

MATERIALS AND METHODS

We performed a blinded clinical study (ClinicalTrials.gov Identifier NCT00400894) from September 2005 to January 2007 in 591 patients who were continuously recruited from 4 European urological clinics. Urine was obtained directly after digital rectal examination and the annexin A3 concentration in urine was quantified by Western blot. Statistical analysis included combinations of annexin A3 with total, percent free, complexed and percent complexed prostate specific antigen.

RESULTS

Combined readouts of prostate specific antigen and urinary annexin A3 were superior to all others with an area under the ROC curve of 0.82 for a total prostate specific antigen range of 2 to 6 ng/ml, 0.83 for a total prostate specific antigen range of 4 to 10 ng/ml and 0.81 in all patients. The best performing prostate specific antigen derivative was percent free prostate specific antigen with an area under the ROC curve of 0.68 for a total prostate specific antigen range of 2 to 6 ng/ml, 0.72 for a total prostate specific antigen range of 4 to 10 ng/ml and 0.73 in all patients. Annexin A3 has an inverse relationship to cancer and, therefore, its specificity was much better than that of prostate specific antigen.

CONCLUSIONS

Annexin A3 quantification in urine provides a novel noninvasive biomarker with high specificity. Annexin A3 is complementary to prostate specific antigen or to any other cancer marker. It has a huge potential to avoid unnecessary biopsies with a particular strength in the clinically relevant large group of patients who have a negative digital rectal examination and prostate specific antigen in the lower range of values (2 to 10 ng/ml).

Trans-rectal ultrasound-coupled near-infrared optical tomography of the prostate, part I: simulation

We investigate the feasibility of trans-rectal optical tomography of the prostate using an endo-rectal near-infrared (NIR) applicator that is to be integrated with a trans-rectal ultrasound (TRUS) probe. Integration with TRUS ensures accurate endo-rectal positioning of the NIR applicator and the utility of using TRUS spatial prior information to guide NIR image reconstruction. The prostate NIR image reconstruction is challenging even with the use of spatial prior owing to the anatomic complexity of the imaging domain. A hierarchical reconstruction algorithm is developed that implements cascaded initial-guesses for nested domains. This hierarchical image reconstruction method is then applied to evaluating a number of NIR applicator designs for integration with a sagittal TRUS transducer. A NIR applicator configuration feasible for instrumentation development is proposed that contains one linear array of optodes on each lateral side of the sagittal TRUS transducer. The performance of this NIR applicator is characterized for the recovery of single tumor mimicking lesion as well as dual targets in the prostate. The results suggest a strong feasibility of transrectal prostate imaging by use of the endo-rectal NIR/US probe.

Computer-assisted diagnosis of prostate cancer using DCE-MRI data: design, implementation and preliminary results

OBJECTS

We present computer-assisted diagnosis (CAD) software designed to improve prostate cancer detection using perfusion MRI data.

METHODS

In addition to standard visualization features, this software allows for the 2D and multislice 2D contouring of suspicious areas based on a seeded region growing algorithm, and area labeling based on zonal anatomy. Tumor volume assessment and the semiquantitative analysis of DCE-MRI sequences can both be performed. We retrospectively analyzed DCE-MRI examinations of 100 patients and found 121 lesions showing a suspiciously high intensity with early enhancement in 84 of them. Seventy-one patients turned out to be malignant, whereas 50 were benign. Based on an analysis of the median wash-in and wash-out values of these foci, we designed a standardized 5-level cancer suspicion score (ranging from "probably benign" to "highly suspicious"). This comprehensive score provides a scaled likelihood of malignancy in the region of interest taking account of its location in relation to prostate zonal anatomy. We compared its accuracy with that of visual assessments of time-intensity curves performed by specialist and non-specialist radiologists.

RESULTS

Parameters of the scoring algorithm were designed to provide the greatest possible sensitivity in our sample population. A re-substitution evaluation provided an Se/Sp of 100/45% for peripheral zone cancer, and 100/40% for transition zone cancer characterization. When identifying malignant areas using time-intensity curves data, this simple algorithm performed significantly better (AUC = 0.77) than a non-specialist (AUC = 0.57, P < 0.0001) radiologist, and better than a trained (AUC = 0.70) radiologist, although this difference was not significant.

CONCLUSION

Our new prostate MRI CAD software provides a standardized cancer suspicion score for suspicious foci detected in DCE-MRI T1-w images. Our results suggest that it may improve radiologists' performances in prostate cancer identification, especially when they are not specialized in prostate imaging.

Prostate-specific antigen (PSA) kinetics in untreated, localized prostate cancer: PSA velocity vs PSA doubling time

OBJECTIVES

To compare the accuracy of prostate-specific antigen (PSA) velocity (PSAV) vs PSA doubling time (DT) for predicting the repeat biopsy results in men with localized prostate cancer on active surveillance (AS), as the utility of PSAV vs PSADT in untreated prostate cancer has not been well studied.

PATIENTS AND METHODS

Eligible patients had favourable-risk localized prostate cancer (T1/2a, PSA level <or=15 ng/mL, Gleason score <or=3 + 4, and percentage positive biopsy cores <or=50%), and consented to AS between 2002 and 2005. Repeat biopsies were taken after 18-24 months, with adverse histology defined as any of: primary Gleason grade >or=4, >50% cores positive, or initial Gleason score 3 + 3 upgraded to >or=3 + 4. Using all PSA values for the 2 years preceding repeat biopsy, the PSAV and PSADT were calculated using linear regression and the log-slope method (DT = ln2/slope), respectively.

RESULTS

In all, 199 patients were assessable; the median PSAV and PSADT were 0.71 ng/mL/year and 5.29 years, respectively. Fifty-three patients (27%) had adverse histology on repeat biopsy. On univariate analyses, PSAV (P < 0.001) and PSADT (P = 0.019) were associated with adverse histology. The area under the receiver operating characteristic curve for predicting adverse histology was 0.70 and 0.63 for PSAV and PSADT, respectively. The mean difference was 0.07 (95% confidence interval 0.03-0.12; P < 0.001).

CONCLUSIONS

PSAV is more accurate than PSADT for predicting adverse histology on repeat biopsies. These data suggest that PSAV should be used in preference to PSADT to describe PSA kinetics in untreated, localized prostate cancer.

Pathologic stage T2a and T2b prostate cancer in the recent prostate-specific antigen era: implications for unilateral ablative therapy

BACKGROUND

Early detection of small volume prostate cancer (PCa) has led to the concept of focal therapy to treat in an organ-sparing manner. We evaluated trends in pathologic staging among patients with localized PCa undergoing radical prostatectomy (RP), defining the frequency of unilateral cancers during 1988-1995, 1996-2000 and 2001-2006.

METHODS

Data were abstracted from the Duke Prostate Cancer Outcome database selecting 3,676 men with available pathology treated with RP. Based on surgical pathology, trends in as pathological T (pT) stage, pathological Gleason Score (pGS), and percent tumor involvement (PTI) were evaluated.

RESULTS

pT2a increased from 2.8% of men undergoing RP in 1988-1995 to 13.0% during 2001-2006 (P < 0.0005). PTI analysis shifted towards low volume disease, e.g. PTI <or= 5% increased from 10% during 1988-1995, to 37% in 2001-2006 (P < 0.005). Of all pT2a disease throughout 1988-2006, an increase in proportion of pT2a tumors from 10% during 1988-1995 to 69.4% during 2001-2006 was identified. Over three eras, pT2a had minimal (65% had PTI <or= 5%) or small volume (14% had PTI 5.01-10.00) disease, and 59% were low grade (pGS <or= 6). Using a Cox Hazard model, pT2a versus pT2b disease, surgical margins, PTI, and PSA statistically contributed to PSA disease-free survival in the contemporary era 2001-2006.

CONCLUSIONS

The increasing prevalence of unilateral pT2a/T2b PCa characterizes a growing proportion of men recently electing RP. These tumors are associated with lower PTI, pGS <or= 7, and demonstrated better PSA-free survival in the 2001-2006 era. These low risk pathologic characteristics may allow for unilateral focal therapy in carefully selected patients.

Cancer screening: a mathematical model relating secreted blood biomarker levels to tumor sizes

BACKGROUND

Increasing efforts and financial resources are being invested in early cancer detection research. Blood assays detecting tumor biomarkers promise noninvasive and financially reasonable screening for early cancer with high potential of positive impact on patients' survival and quality of life. For novel tumor biomarkers, the actual tumor detection limits are usually unknown and there have been no studies exploring the tumor burden detection limits of blood tumor biomarkers using mathematical models. Therefore, the purpose of this study was to develop a mathematical model relating blood biomarker levels to tumor burden.

METHODS AND FINDINGS

Using a linear one-compartment model, the steady state between tumor biomarker secretion into and removal out of the intravascular space was calculated. Two conditions were assumed: (1) the compartment (plasma) is well-mixed and kinetically homogenous; (2) the tumor biomarker consists of a protein that is secreted by tumor cells into the extracellular fluid compartment, and a certain percentage of the secreted protein enters the intravascular space at a continuous rate. The model was applied to two pathophysiologic conditions: tumor biomarker is secreted (1) exclusively by the tumor cells or (2) by both tumor cells and healthy normal cells. To test the model, a sensitivity analysis was performed assuming variable conditions of the model parameters. The model parameters were primed on the basis of literature data for two established and well-studied tumor biomarkers (CA125 and prostate-specific antigen [PSA]). Assuming biomarker secretion by tumor cells only and 10% of the secreted tumor biomarker reaching the plasma, the calculated minimally detectable tumor sizes ranged between 0.11 mm(3) and 3,610.14 mm(3) for CA125 and between 0.21 mm(3) and 131.51 mm(3) for PSA. When biomarker secretion by healthy cells and tumor cells was assumed, the calculated tumor sizes leading to positive test results ranged between 116.7 mm(3) and 1.52 x 10(6) mm(3) for CA125 and between 27 mm(3) and 3.45 x 10(5) mm(3) for PSA. One of the limitations of the study is the absence of quantitative data available in the literature on the secreted tumor biomarker amount per cancer cell in intact whole body animal tumor models or in cancer patients. Additionally, the fraction of secreted tumor biomarkers actually reaching the plasma is unknown. Therefore, we used data from published cell culture experiments to estimate tumor cell biomarker secretion rates and assumed a wide range of secretion rates to account for their potential changes due to field effects of the tumor environment.

CONCLUSIONS

This study introduced a linear one-compartment mathematical model that allows estimation of minimal detectable tumor sizes based on blood tumor biomarker assays. Assuming physiological data on CA125 and PSA from the literature, the model predicted detection limits of tumors that were in qualitative agreement with the actual clinical performance of both biomarkers. The model may be helpful in future estimation of minimal detectable tumor sizes for novel proteomic biomarker assays if sufficient physiologic data for the biomarker are available. The model may address the potential and limitations of tumor biomarkers, help prioritize biomarkers, and guide investments into early cancer detection research efforts.

Cancer screening in men

Cancer screening is one of the most common requests directed to primary care physicians in the office setting. In this article, we look at current recommendations, evidence for, and controversy surrounding screening for cancers of the lung, colon, and prostate, which together account for 51% of cancer deaths in men. We also look at screening for testicular cancer, which, although a relatively minor contributor to cancer mortality, is a prototypically male cancer with a proposed screening test.

Detailed analysis of histopathological parameters in radical prostatectomy specimens and PCA3 urine test results

BACKGROUND

Due to the drawbacks of serum prostate-specific antigen, there is an ongoing search for new diagnostic and prognostic prostate cancer (PCa) markers. PCA3 has proven to be of value in the diagnosis of PCa. However, so far few attempts have been made to investigate the prognostic value of PCA3. Our objective was to further investigate the prognostic value of PCA3.

METHODS

In this study we correlated the PCA3 score in urinary sediments after digital rectal examination in 62 men with the classical prognostic parameters assessed in radical prostatectomy specimens (i.e. Gleason score, pathological tumor stage and total tumor volume) and moreover, with the expression of three immunohistochemical markers for PCa biological aggressiveness (i.e. E-cadherin, alpha-catenin and EZH2). The results from this study serve as a reflection on and a valuable adjunct to recently published results.

RESULTS

We did not find a significant correlation of the PCA3 score with the classical prognostic parameters assessed in radical prostatectomy specimens or the expression of the immunohistochemical markers for PCa biological aggressiveness. However, we did observe a trend for a higher PCA3 score in significant PCa versus insignificant PCa, aberrant E-cadherin staining versus normal E-cadherin staining and increased EZH2 staining versus normal EZH2 staining.

CONCLUSIONS

In this study we could not prove the prognostic value of PCA3. Further research with large numbers of men and adequate follow-up is needed to provide a definitive answer to the question if PCA3 is not only a diagnostic but also a prognostic PCa marker.

Evolutionary conservation of zinc finger transcription factor binding sites in promoters of genes co-expressed with WT1 in prostate cancer

BACKGROUND

Gene expression analyses have led to a better understanding of growth control of prostate cancer cells. We and others have identified the presence of several zinc finger transcription factors in the neoplastic prostate, suggesting a potential role for these genes in the regulation of the prostate cancer transcriptome. One of the transcription factors (TFs) identified in the prostate cancer epithelial cells was the Wilms tumor gene (WT1). To rapidly identify coordinately expressed prostate cancer growth control genes that may be regulated by WT1, we used an in silico approach.

RESULTS

Evolutionary conserved transcription factor binding sites (TFBS) recognized by WT1, EGR1, SP1, SP2, AP2 and GATA1 were identified in the promoters of 24 differentially expressed prostate cancer genes from eight mammalian species. To test the relationship between sequence conservation and function, chromatin of LNCaP prostate cancer and kidney 293 cells were tested for TF binding using chromatin immunoprecipitation (ChIP). Multiple putative TFBS in gene promoters of placental mammals were found to be shared with those in human gene promoters and some were conserved between genomes that diverged about 170 million years ago (i.e., primates and marsupials), therefore implicating these sites as candidate binding sites. Among those genes coordinately expressed with WT1 was the kallikrein-related peptidase 3 (KLK3) gene commonly known as the prostate specific antigen (PSA) gene. This analysis located several potential WT1 TFBS in the PSA gene promoter and led to the rapid identification of a novel putative binding site confirmed in vivo by ChIP. Conversely for two prostate growth control genes, androgen receptor (AR) and vascular endothelial growth factor (VEGF), known to be transcriptionally regulated by WT1, regulatory sequence conservation was observed and TF binding in vivo was confirmed by ChIP.

CONCLUSION

Overall, this targeted approach rapidly identified important candidate WT1-binding elements in genes coordinately expressed with WT1 in prostate cancer cells, thus enabling a more focused functional analysis of the most likely target genes in prostate cancer progression. Identifying these genes will help to better understand how gene regulation is altered in these tumor cells.

Diabetes mellitus and prostate cancer risk in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial

Objective

A history of diabetes has been fairly consistently related to a reduced prostate cancer risk, but previous investigations have not always addressed whether the relation with diabetes varies by prostate cancer aggressiveness or the association between diabetes and prostate cancer is modified by physical activity level and body mass, variables closely related to glucose metabolism.

Methods

We prospectively examined the diabetes–prostate cancer risk relationship among 33,088 men in the screening arm of the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial.

Results

During 8.9 years follow-up, we ascertained 2,058 incident prostate cancer cases. Diabetes history was related to decreased risk of total prostate cancer (RR = 0.80, 95% CI = 0.68–0.95). The apparent protection afforded by diabetes was primarily due to the inverse relation with non-aggressive disease (i.e., the combination of low grade (Gleason sum <8) and low stage (clinical stages I or II); RR = 0.75; 95% CI = 0.62–0.91). In contrast, no association was noted between diabetes and aggressive disease (i.e., high grade or high stage (Gleason sum ≥8 or clinical stages III or IV); RR = 1.04, 95% CI = 0.74–1.45). In further analyses, the association between diabetes and aggressive prostate cancer was suggestively positive for men who were lean (RR = 1.64, 95% CI = 0.87–3.07; BMI < 25 kg/m²) and it was positive for men who were the most physically active (RR = 1.63; 95% CI = 1.07–2.62; 3+ hours vigorous activity/week). By comparison, no relations of diabetes to aggressive prostate cancer were noted for their heavier or physically less active counterparts (p-value for tests of interaction = 0.10 and 0.03 BMI and physical activity, respectively).

Conclusion

In this study, diabetes showed divergent relations with prostate cancer by tumor aggressiveness. Specifically, diabetes was inversely associated with early stage prostate cancer but it showed no relation with aggressive prostate cancer. Exploratory analyses suggested a positive association between diabetes and aggressive prostate cancer in the subgroup of men with a low BMI.

Prostatic fluid electrolyte composition for the screening of prostate cancer: a potential solution to a major problem

Early detection is the key to effective treatment of prostate cancer, and to the prevention of deaths due to progression to untreatable advanced stage cancer. Because of mitigating factors, especially benign prostatic hyperplasia (BPH), that result in a low accuracy (about 60%) of prostate-specific antigen (PSA) testing, there is an urgent need for a more reliable biomarker for the identification of early stage through advanced stage prostate cancer and 'at-risk' individuals. To address this issue we propose that changes in prostatic fluid composition could provide accurate and reliable biomarkers for the screening of prostate cancer. Most notable is the consistent and significant decrease in citrate and zinc that is associated with the development and progression of prostate cancer. In this review we provide the clinical and physiological basis and the evidence in support of the utility of prostatic fluid analysis as an effective approach for screening/detection of prostate cancer, especially early stage and 'at-risk' subjects. The problem of BPH interference that plagues PSA testing is eliminated in the potential prostatic fluid biomarkers. The potential development of rapid, simple, direct, accurate clinical tests provides additional advantageous conditions. Further exploration and development of citrate, zinc and other electrolytes as prostatic fluid biomarkers are urgently needed to address this critical prostate cancer issue.

Recurrent gene fusions in prostate cancer

The discovery of recurrent gene fusions in a majority of prostate cancers has important clinical and biological implications in the study of common epithelial tumours. Gene fusion and chromosomal rearrangements were previously thought to be primarily the oncogenic mechanism of haematological malignancies and sarcomas. The prostate cancer gene fusions that have been identified thus far are characterized by 5' genomic regulatory elements, most commonly controlled by androgen, fused to members of the Ets family of transcription factors, leading to the overexpression of oncogenic transcription factors. Ets gene fusions probably define a distinct class of prostate cancer, and this might have a bearing on diagnosis, prognosis and rational therapeutic targeting.

The performance of prostate specific antigen for predicting prostate cancer is maintained after a prior negative prostate biopsy

PURPOSE

It has been suggested that prostate specific antigen has no predictive value for prostate cancer after a first negative biopsy has been performed. We compared the performance operating characteristics of prostate specific antigen for prostate cancer between a first and subsequent prostate biopsy in a group of men with complete verification of cancer status.

MATERIALS AND METHODS

From the 18,882 participants in the Prostate Cancer Prevention Trial we examined men in the placebo group who had only a first biopsy or a first and second prostate biopsy with a prostate specific antigen and digital rectal examination within 1 year before each biopsy. The receiver operating characteristic curve was estimated for prostate specific antigen for detection of prostate cancer on the first biopsy compared to the second, and the C-statistics were compared.

RESULTS

Of this group 5,608 men had a first biopsy and 687 of those with a negative first biopsy underwent a second biopsy. The C-statistic was 0.650 (95% CI 0.632, 0.668) for the first biopsy and 0.664 (95% CI 0.607, 0.721) for the second biopsy. The C-statistic for the second biopsy was statistically significantly greater than 0.5 (p <0.001) and overlapped with that from the first biopsy.

CONCLUSIONS

Prostate specific antigen does not lose predictive value for the detection of prostate cancer even after a first biopsy shows no evidence of cancer, and its performance characteristics are only slightly decreased.

Associations of lower urinary tract symptoms with prostate-specific antigen levels, and screen-detected localized and advanced prostate cancer: a case-control study nested within the UK population-based ProtecT (Prostate testing for cancer and Treatment) study

OBJECTIVE

To determine associations of lower urinary tract symptoms (LUTS) with prostate-specific antigen (PSA) levels and screen-detected localized and advanced prostate cancer.

SUBJECTS AND METHODS

A case-control study nested within the UK population-based ProtecT (Prostate testing for cancer and Treatment) study. Men aged 50-69 years were invited for PSA testing and those with a PSA level of >or=3.0 ng/mL were invited for biopsy. We determined whether LUTS were associated with a PSA level of >or=3.0 ng/mL and prostate cancer using logistic regression models adjusted for age, family history of prostate cancer and PSA level as appropriate. Areas under receiver operating characteristic curves (AUC) were compared between models with and without symptoms.

RESULTS

In all, 65 871 men had a PSA test: 7251 had a PSA level of >or=3.0 ng/mL including 2467 subsequently diagnosed with prostate cancer (2119 localized, 348 advanced). LUTS were positively associated with a PSA level of >or=3.0 ng/mL: odds ratios (ORs) were 1.18 (95% confidence interval, CI 1.01-1.38), 1.69 (95% CI 1.32-2.16), and 1.60 (95% CI 1.33-1.93) for daytime urination frequency (hourly vs less frequent), urgency and hesitancy (most/all the time vs never), respectively. LUTS among men with a PSA level of >or=3 ng/mL were negatively associated with prostate cancer: ORs were 0.44 (95% CI 0.22-0.83), 0.74 (95% CI 0.63-0.87), and 0.83 (95% CI 0.73-0.94) for nocturia (4+ vs 0), leakage and hesitancy (occasionally/sometimes vs never), respectively. LUTS improved the prediction of a PSA level of >or=3.0 ng/mL (AUC 0.635 vs 0.606, P < 0.001) and prostate cancer (AUC 0.661 vs 0.638; P < 0.001).

CONCLUSIONS

A history of LUTS before PSA testing marginally improves the prediction of an individual's risk for prostate cancer; men with a PSA level of >or=3 ng/mL and LUTS were more likely to be diagnosed with benign disease than prostate cancer.