Delays in cancer detection using 2 and 4-year screening intervals for prostate cancer screening with initial prostate specific antigen less than 2 ng/ml

Purpose:The American Urological Association and American Cancer Society advocate annual screening with serum prostate specific antigen (PSA) and digital rectal examination starting at age 50 years in the general population and earlier in men at high risk. Some groups have suggested that screening at 2 or 4-year intervals may be sufficient in men with initial PSA 2 ng/ml or less. We reviewed the records of men enrolled in a PSA and digital rectal examination based prostate cancer screening study to determine the extent to which the diagnosis of cancer would have been delayed using a 2 or 4-year screening interval.Materials and Methods:We evaluated 18,140 volunteers in a prostate cancer screening study in whom PSA was less than 2 ng/ml at initial screening and who were screened at 6-month to 1-year intervals for up to 8 years. We evaluated the cancers detected in these intervals to determine the possible delay in cancer diagnosis that would occur using prolonged screening intervals. We report the overall cancer detection rate, clinical and pathological tumor stage, and Gleason grade of the cancers detected.Results:Excluding 70 men in whom prostate cancer was detected at initial evaluation 2.0% had prostate cancer detected during the next 8 years (mean 21.6 cancers per 6 months, median 20, range 12 to 33). Using a hypothetical 2-year screening interval cancer detection 62% would have been delayed by 4 to 20 months. Using a hypothetical 4-year screening interval cancer detection would have been delayed in 77% of men by 4 to 44 months. Of the tumors detected 100% were clinically localized, 77% were pathologically organ confined and 29% had a Gleason score of 7 or greater.Conclusions:The 2 or 4-year PSA screening interval in men with initial serum PSA less than 2 ng/ml would result in substantial delays in prostate cancer detection. To our knowledge the extent to which these delays would affect treatment outcomes is undetermined.     

Prostate cancer detection at low prostate specific antigen

PURPOSE: At low prostate specific antigen (PSA) the indication for prostate biopsy is usually an abnormal digital rectal examination. We evaluate the diagnostic value of PSA, digital rectal examination, transrectal ultrasonography and tumor characteristics at low PSA (0 to 4.0 ng./ml.). We confirm and add to recent evidence that digital rectal examination has a low predictive value and that many significant cancers at this PSA range may be missed. MATERIALS AND METHODS: From 1994 to 1997 a total of 10,523 participants 54 to 74 years old were randomized to screening in the Rotterdam section of the European Randomized Study of Screening for Prostate Cancer. Of the participants 9,211 (87.5%) had PSA less than 4.0 ng./ml., and underwent digital rectal examination and transrectal ultrasonography. Expected rates of prostate cancer detection were calculated using logistic regression analysis. Radical prostatectomy was performed in about half of the 478 men diagnosed with prostate cancer. Tumors were characterized by pT category, Gleason score and cancer volume in 166 processed radical prostatectomy specimens. In 50 of these cases PSA was 0 to 4.0 ng./ml. RESULTS: The positive predictive value of digital rectal examination and transrectal ultrasonography at PSA 0 to 4.0 ng./ml. was only 9.7%. Positive predictive value strongly depended on PSA. Sensitivity was calculated by using estimates of the prevalence of sextant biopsy detectable prostate cancers. Of 760 detectable cancers 478 (67%) were diagnosed irrespective of PSA in men screened with digital rectal examination, transrectal ultrasonography and PSA. Only 127 of 348 detectable prostate cancers (36.5%) were actually diagnosed in men with PSA 2 to 4 mg./ml. The importance of these missed cancers was evaluated with parameters of tumor aggressiveness within PSA ranges. CONCLUSIONS: Approximately half of the tumors missed with PSA 0 to 4 ng./ml. had aggressive characteristics (Gleason score 7 or greater, Gleason 4-5 components) and were organ confined. These tumors should be diagnosed and treated according to the present understanding of their natural history. More sensitive and selective screening strategies are needed. Presently a wrong "window of opportunity" is used for early detection of prostate cancer.     

Prognostic features in men who died of prostate cancer

PURPOSE: Since the advent of widespread prostate specific antigen (PSA) based screening in the United States, the risk of over diagnosis as well as delayed diagnosis due to existing PSA thresholds has become a concern. Treatment decision planning is generally linked to prognostic variables, most notably PSA, clinical stage and Gleason grade. We examined these and other prognostic variables in a cohort of men who ultimately died of prostate cancer. MATERIALS AND METHODS: Of 413 men with prostate cancer in a cohort in San Antonio, Texas between 1993 and 2003 who died of disease we identified 211 who died as a direct result of prostate cancer. In these cases we assessed presenting symptoms, PSA history, tumor stage and Gleason score at diagnosis. RESULTS: Of the 211 men 141 (67%) underwent screening for prostate cancer prior to diagnosis. Of 190 men with PSA data at diagnosis available 7 (3.7%) had PSA less than 4.0 ng/ml and 27 (14%) had PSA 4.0 to 10.0 ng/ml. Clinical stage distribution was cT1 in 21.1% of cases, cT2 in 50.7% and cT3 in 26.8%. Of 167 men for whom biopsy Gleason grade was available 16.8%, 16.2%, 24% and 43.1% had Gleason sum 5 or less, 6, 7 and 8 or higher, respectively. CONCLUSIONS: While most men who ultimately die of prostate cancer have poor prognostic features, a substantial number have features associated with a potentially good prognosis, including low PSA and low Gleason grade. Many men who died of prostate cancer had undergone prior screening. These data demonstrate the need for improved markers of prognosis and continued assessment of the efficacy of screening with PSA.     

Usefulness of prostate-specific antigen (PSA) rise as a marker of prostate cancer in men treated with dutasteride: lessons from the REDUCE study

Study Type – Prognostic (RCT) Level of Evidence 1b What's known on the subject? and What does the study add? Previous studies used the decrease in PSA after 6 months of dutasteride treatment as a new ‘baseline’ PSA value from which subsequent rises may serve as a warning for prostate cancer; however, PSA tends to continue to decrease as dutasteride treatment continues. By comparing positive biopsy rates in the REDUCE study using any rise from nadir in the dutasteride arm and standard PSA decision criteria (NCCN) in the placebo arm, we demonstrated that the ability to detect prostate cancer and high grade prostate cancer is maintained with dutasteride treatment.

OBJECTIVES

? To determine if dutasteride‐treated men can be monitored safely and adequately for prostate cancer based on data from the Reduction by Dutasteride in Prostate Cancer Events (REDUCE) study. ? To analyse whether the use of treatment‐specific criteria for repeat biopsy maintains the usefulness of prostate‐specific antigen (PSA) level for detecting high grade cancers.

PATIENTS AND METHODS

? The REDUCE study was a randomized, double‐blind, placebo‐controlled investigation of whether dutasteride (0.5 mg/day) reduced the risk of biopsy‐detectable prostate cancer in men with a previous negative biopsy. ? The usefulness of PSA was evaluated using biopsy thresholds defined by National Comprehensive Cancer Network guidelines in the placebo group and any rise in PSA from nadir (the lowest PSA level achieved while in the study) in the dutasteride group. ? The number of cancers detected on biopsy in the absence of increased/suspicious PSA level as well as sensitivity, specificity, positive predictive value and negative predictive value for high grade prostate cancer detection were analysed by treatment group. ? Prostate cancer pathological characteristics were compared between men who did and did not meet biopsy thresholds.

RESULTS

? Of 8231 men randomized, 3305 (dutasteride) and 3424 (placebo) underwent at least one prostate biopsy during the study and were included in the analysis. ? If only men meeting biopsy thresholds underwent biopsy, 25% (47/191) of Gleason 7 and 24% (7/29) of Gleason 8–10 cancers would have been missed in the dutasteride group, and 37% (78/209) of Gleason 7 and 22% (4/18) Gleason 8–10 cancers would have been missed in the placebo group. ? In both groups, the incidence of Gleason 7 and Gleason 8–10 cancers generally increased with greater rises in PSA. ? Sensitivity of PSA kinetics was higher and specificity was lower for the detection of Gleason 7–10 cancers in men treated with dutasteride vs placebo. ? Men with Gleason 7 and Gleason 8–10 cancer meeting biopsy thresholds had greater numbers of positive cores, percent core involvement, and biopsy cancer volume vs men not meeting thresholds.

CONCLUSION

? Using treatment‐specific biopsy thresholds, the present study shows that the ability of PSA kinetics to detect high grade prostate cancer is maintained with dutasteride compared with placebo in men with a previous negative biopsy. ? The sensitivity of PSA kinetics with dutasteride was similar to (Gleason 8–10) or higher than (Gleason 7–10) the placebo group; however, biopsy decisions based on a single increased PSA measurement from nadir in the dutasteride group resulted in a lower specificity compared with using a comparable biopsy threshold in the placebo group, indicating the importance of confirmation of PSA measurements.     

Prospective detection of clinically relevant prostate cancer in the prostate specific antigen range 1 to 3 ng./ml. combined with free-to-total ratio 20% or less: the Aarau experience

PURPOSE: Little is known about the incidence rate and clinical relevance of prostate cancer in a low prostate specific antigen (PSA) level. In a prospective PSA based screening study we investigated the incidence and clinicopathological features of prostate cancer that occurred within PSA range 1 to 3 ng./ml. when the free-to-total ratio was 0.20 or less. MATERIALS AND METHODS: Men participating in the Aarau, Switzerland, section of the European Randomized Study of Screening for Prostate Cancer between October 1998 and July 2000 were included in the study. As a side study, all men with PSA between 1 and 3 ng./ml. and free-to-total ratio 0.20 or less were invited to undergo further evaluation with ultrasound guided sextant prostate biopsy. RESULTS: Overall, 168 (7.8%) participants fulfilled inclusion criteria. A total of 158 (94%) patients underwent prostate biopsy, and prostate cancer was detected in 17 (10.8%). There were no statistically significant differences between prostate cancer and benign prostatic hyperplasia in regard to patient age (60.7 versus 59.8 years), prostate volume (23.9 versus 23.0 cc), PSA (1.98 versus 1.86 ng./ml.), free-to-total ratio (0.161 versus 0.160), PSA density (0.089 versus 0.076 ng./ml.) or PSA transition zone density (0.33 versus 0.24 ng./ml., respectively). Median Gleason score was 5 on prostate biopsy versus 6 on retropubic prostatectomy specimen. Of the 14 patients who underwent surgery there were positive lymph nodes in 1, stage pT3b Gleason 7 disease in 1, and pathologically organ confined Gleason 5 in 2, Gleason 6 in 5 and Gleason 7 in 5. Mean tumor volume was 1.01 cc (range 0.02 to 5.17). There were 2 (14.3%) insignificant (less than 0.2 cc, Gleason grade 3 or less), 1 (7.1%) minimal (less than 0.5cc, Gleason grade 3 or less) and 11 (78.6%) clinically relevant and potentially harmful cancers. CONCLUSIONS: There is a significant number of prostate cancer cases diagnosed at PSA as low as 1 to 3 ng./ml. A majority of these tumors are clinically significant. This free-to-total ratio range may be helpful for identifying prostate cancer. The "window of opportunity" for detection of curable cancer may change in populations with higher life expectancy towards lower PSA. Lack of specificity and characterization of tumor aggressiveness remains an unsolved issue for PSA.     

Five-year results of prostate specific antigen (PSA) screening in Yokosuka City--comparative study between PSA-screened group and non-screened group

A mass screening of subjects for prostate specific antigen (PSA) was conducted to investigate whether this method is effective in detection of early stage prostate cancer. From 2001 to 2005, 1022 patients in Yokosuka City with pathologically diagnosed prostate cancer by using prostate needle biopsy were divided into screened (S: 276 patients) and non-screened (NS: 746 patients) groups. Clinical factors (mean age, PSA at diagnosis, clinical stage, Gleason score, WHO classification, cases of radical prostatectomy) were evaluated and analyzed. Statistical significance was analyzed by Mann-Whitney's U-test. The mean age was 70.7 and 72.7 (p<0.0001) in the S group and NS group, respectively; mean PSA at diagnosis was 10.5 and 18.6 ng/ml (P=0.0139); percentage of organ-confined disease (T2b or lower clinical stage), 75 and 55 (p<0.0001); percentage of non-metastatic diseases was 92 and 77 (p<0.001) and percentage of pathologically poor-risk cancer (8 or more Gleason score) was 22 and 38 (p=0.0004), respectively. In conclusion, PSA mass screening was found useful to detect early stage prostate cancer in Yokosuka City. Further studies should be conducted to determine whether PSA mass screening will be able to decrease mortality of prostate cancer.     

PSA testing: an evolving relationship with prostate cancer screening

PSA testing has made prostate cancer screening a reality for men in many parts of the world, but its benefit for men's health continues to be debated. In men exposed to PSA testing, there has been a well-documented change in the presentation of prostate cancer with a shift towards earlier pathological stage, not without justifiable concern about over-diagnosis by prostate biopsy. Increasingly, men now diagnosed with early stage cancer have previous PSA exposure and are selected for biopsy based on PSA change in relation to cutoff values. Some recent observations suggest that PSA may no longer be an effective marker for early stage tumours, with PSA elevation failing to discriminate tumour-specific characteristics from benign gland enlargement. Traditionally, variation in pathological stage of clinically localised prostate cancer at diagnosis has related to clinical stage, PSA and biopsy Gleason grade, but with distinctions based upon these three assessments declining and an increasing proportion of organ-confined tumours at presentation, new methods of cancer detection and prognostic assessment are now required. Molecular technologies hold great promise in this respect, and in the future biomarker signatures are likely to overshadow total PSA for guiding early diagnosis and prognostic assessment. While arguments about prostate screening will continue, owing not least to its feasibility, future debate is likely to focus increasingly on technological advances and molecular profiling of these notoriously heterogeneous tumours.     

Prostate cancer detection and dutasteride: utility and limitations of prostate-specific antigen in men with previous negative biopsies

Context

We addressed the question whether the change of serum prostate-specific antigen (PSA) in men who use 5α-reductase inhibitor (5-ARI) dutasteride is sensitive for the detection of aggressive prostate cancer (PCa).

Objective

The case of a man using dutasteride diagnosed with Gleason 7 transition zone cancer at biopsy indicated by a rising PSA is described. The following issues are discussed: (1) Is a rise of PSA in patients using dutasteride predictive of aggressive PCa in men with prior negative biopsies? (2) Is it safe not to biopsy men using dutasteride who do not show a rising PSA? (3) How can we avoid potentially unnecessary biopsies in men using dutasteride without a rising PSA?

Evidence acquisition

We reviewed the recent literature addressing our objective that relates to two studies: the Prostate Cancer Prevention Trial and the Reduction by Dutasteride of Prostate Cancer Events trial.

Evidence synthesis

In men using dutasteride, the positive predictive value/detection rate of Gleason 7–10 PCa is 13.2% and 4.0% for men with and without a rising PSA, respectively. However, a substantial proportion of Gleason 7–10 cases (42.9%) would be missed if a rising PSA was used as the only biopsy indication. Currently available data do not provide selective mechanisms to diagnose these cancers.

Conclusions

A rising PSA for a patient using dutasteride should be an indication for prostate biopsies. Currently, in the case of stable PSA a biopsy may still be considered. Options for a selective approach are therefore suggested in this review to avoid unnecessary biopsies and to achieve a more selective PCa detection in men on 5-ARI treatment.     

A novel serum marker, total prostate secretory protein of 94 amino acids, improves prostate cancer detection and helps identify high grade cancers at diagnosis

PURPOSE: New biomarkers for prostate cancer are needed. We determined whether a novel serum marker, total PSP94 can be used to accomplish these goals. MATERIALS AND METHODS: We conducted a case-control study of 1,212 men with no previous history of prostate cancer and who underwent a prostate biopsy from 1998 to 2000 because of an increased PSA or an abnormal DRE. Serum PSP94 levels were assessed using a sandwich enzyme-linked immunosorbent assay technique. Cases were patients with prostate cancer, and controls were patients who had no evidence of cancer. Multivariate logistic regression analysis was used to determine whether or not PSP94 levels improved the predictive value for prostate cancer. RESULTS: Of the 1,212 men 596 (49.2%) had cancer detected. The median PSP94 level was significantly lower among cases (2.60 ng/ml) than among controls (3.40 ng/ml, p <0.0001). The adjusted odds ratios for the presence of prostate cancer for patients with the lowest quartile of PSP94, compared to patients in the highest quartile was 2.70 (95% CI 1.8 - 4.0, p <0.0001). Among a subgroup of 649 men in whom PSA had a low predictive value (PSA less than 20 ng/ml, normal DRE and less than 70 years), 260 (40.1%) were found to have cancer. In this subgroup total PSP94 levels helped discriminate between patients with high grade disease (Gleason score 8 or more, median 1.90 ng/ml), moderate grade disease (Gleason score 7, median 2.34 ng/ml) and low grade disease (Gleason score 6 or less, median 2.60 ng/ml, p = 0.007). PSA and the FTPSA were not able to distinguish between patients with different grades in this group. CONCLUSIONS: Patients with low total PSP94 levels had a high probability for having prostate cancer detected at biopsy. The total PSP94 level was able to help identify patients with high grade disease among a subset of patients in whom PSA and FTPSA are least informative.     

Evaluation of proprostate specific antigen for early detection of prostate cancer in men with a total prostate specific antigen range of 4.0 to 10.0 ng/ml

PURPOSE: In contemporary screening populations a major drawback of prostate specific antigen (PSA) is its relative lack of specificity, especially in the range of 4 to 10 ng/ml, where prostate cancer is found 25% of the time. ProPSA is a derivative of free PSA (fPSA) consisting of the truncated forms (eg [-2]proPSA, [-4]proPSA or the full-length [-7]proPSA). There is increasing evidence that proPSA is associated preferentially with prostate cancer. The objective of this study was to determine whether proPSA can influence the detection of early prostate cancer. MATERIALS AND METHODS: Archival serum samples obtained from 93 men who underwent a systematic 12-core prostate biopsy (total PSA range 4.0 to 10.0 ng/ml) were assayed for percent free PSA, total PSA and the 3 forms of proPSA (Hybritech Tandem Assays Beckman Coulter Access, Beckman Coulter, Inc., Brea, California). Free PSA, the cumulative sum of individual proPSA forms ([-2], [-4] and [-7], or sum-proPSA) and derivatives were determined. Of the 93 men assessed 41 (44%) had evidence of prostate cancer (76% Gleason 5/6, 19% Gleason 7 and 5% Gleason 8). Prostate volume was measured at systematic 12-core biopsy for the detection of prostate cancer. Results were analyzed using univariate and multivariate logistic regression (LR) nonparametric statistical methods. RESULTS: Using univariate LR, fPSA, percent fPSA (%fPSA), percent sum-proPSA and prostate volume significantly (p <0.05) differentiated men with prostate cancer from those with benign disease. However, applying stepwise backward multivariate LR, total PSA, %fPSA and sum-proPSA were retained and generated a receiver operator characteristic curve with an area under the curve of 76.6%. At 90% sensitivity these 3 variables collectively achieved a specificity of 44% for the detection of prostate cancer. Individually, the 3 retained variables had a specificity of 23% (total PSA), 33% (%fPSA) and 13% (sum-proPSA). CONCLUSIONS: Sum-proPSA, total PSA and %fPSA in combination improve the specificity of early prostate cancer detection in men with a total PSA of 4 to 10 ng/ml compared with the results of individual PSA molecular forms measured.     

Relationship between initial prostate specific antigen level and subsequent prostate cancer detection in a longitudinal screening study

PURPOSE: Previous studies of archived blood samples from nonscreened populations have shown an association between the prostate specific antigen (PSA) and the subsequent detection of prostate cancer. In the current study we evaluated the relationship between the initial screening PSA and the subsequent risk of prostate cancer detected in a prospective, longitudinal screening study. We also examined the relationship between initial PSA and the clinicopathological features of the cancers detected. MATERIALS AND METHODS: Between May 1991 and November 2001 we enrolled 26,111 volunteers in our PSA and digital rectal examination based prostate cancer screening study. The men were followed biannually or annually depending on the results of previous screening tests. The chi-square and Kruskal-Wallis tests were used to compare the clinical stage, pathological stage and Gleason score of subsequently detected prostate cancers as well as the time to cancer detection in different initial screening PSA strata. RESULTS: The initial screening PSA stratum was strongly associated with the subsequent detection of prostate cancer as well as the clinicopathological stage and grade of the cancers detected. CONCLUSIONS: Even in the lower PSA ranges initial screening serum PSA can help identify men at increased risk for subsequent prostate cancer detected in a longitudinal screening study.     

Correlation of serum PSA and Gleason score in Nigerian men with prostate cancer

Objective  Prostate cancer is an important cause of morbidity and mortality worldwide. While the predisposing factors are not fully understood, African descent is an important risk factor, and prostate cancer has become the number-one cancer in Nigerian men. This was a retrospective study of the correlation between serum prostate specific antigen (PSA) and Gleason grade and score in patients of Nigerian descent. Patients and Methods  The University College Hospital (UCH) Ibadan Cancer Registry was used to identify and quantify the incidence of prostate cancers occurring between 1998 and 2000. The histological slides of appropriate cases were reviewed to confirm the Gleason grade and score. The serum PSA values were retrieved from the patients' case notes and laboratory files. The data obtained were subjected to statistical analysis to look for associations and correlations. Results  The study included 67 men with prostate adenocarcinoma and PSA measurements who were diagnosed and treated at the UCH Ibadan between January 1998 and December 2000. There was a positive correlation between serum PSA and Gleason grade, as well as between serum PSA and Gleason score in our cohort of Nigerian African men with prostate cancer. PSA levels were significantly lower in patients with stage B disease than in patients with stage D disease. Conclusion  Serum PSA is significantly higher in metastatic than in localized disease. Further studies are necessary to determine biomarkers that complement serum PSA and the Gleason grading system in the prognostication of prostate cancer in African patients.     

Prostate cancer detection in Black and White men with abnormal digital rectal examination and prostate specific antigen less then 4 ng./ml

PURPOSE: Prostate cancer is more common in black than in white American men. Experience in a longitudinal prostate cancer screening program implies that cancer detection is greater in black than in white men with an abnormal digital rectal examination and prostate specific antigen (PSA) less than 4 ng./ml. We investigated potential racial differences in cancer detection in men treated in clinical practice who had an abnormal digital rectal examination and PSA less than 4 ng./ml. MATERIALS AND METHODS: Between January 1992 and December 1999 prostate biopsy was done at a Veterans Affairs Medical Center in 179 black and 357 white men with an abnormal digital rectal examination, PSA less than 4 ng./ml. and no history of prostate surgery. Significant racial differences in demographic and clinical parameters were limited to PSA, which was higher in black men (p = 0.01). RESULTS: Cancer was detected in 38 black (21%) and 65 white (18%) men (p = 0.42). There were no significant racial differences in the PSA adjusted cancer detection rate or in the Gleason score of detected disease. In men with PSA less than 1.0, 1.0 to 1.9, 2.0 to 2.9 and 3.0 to 3.9 ng./ml. the detection rate was 4%, 15%, 27% and 29%, respectively. CONCLUSIONS: In clinical practice prostate cancer detection appears to be equivalent in black and white men when an abnormal digital rectal examination is the only indication of malignancy.     

Results of compliance with prostate cancer screening guidelines

PURPOSE: Current guidelines of the American Cancer Society and the National Comprehensive Cancer Network recommend offering annual prostate cancer screening with prostate specific antigen (PSA) and digital rectal examination (DRE) beginning at age 50 (age 45 in high risk men). There are limited data concerning outcomes if all men followed screening guidelines. We report early outcome data on men who entered a prostate cancer screening study, complied with the screening guidelines and were subsequently diagnosed with prostate cancer. MATERIALS AND METHODS: We reviewed records of men 45 to 59 years old at study entry with a PSA less than 2.6 ng/ml and benign DRE who underwent annual DRE and PSA testing in a screening study between 1991 and 2001. Of 10,174 men with these characteristics, 232 (2.3%) were subsequently diagnosed with prostate cancer. We evaluated PSA, Gleason score, clinical and pathological tumor stage, and treatment outcomes in these men. RESULTS: Median PSA at diagnosis was 3.1 ng/ml (range 0.4 to 9.6). Gleason scores ranged from 4 to 9. All patients had clinically localized disease. Management included predominantly radical prostatectomy (87%) and radiation therapy (10%). Of cancers in which tumor volume was assessed 13% were considered possibly harmless tumors by previously published criteria and 2% were considered possibly rapidly progressive tumors by criteria we set in this study. CONCLUSIONS: Prostate cancer screening using some current guidelines results in the detection of cancers that are organ confined in 79% of patients, possibly harmless in less than 15% and possibly rapidly progressive in 2%.     

Prostate cancer detection strategies

Prostate cancer is the most common malignancy in men and, as a result, there has been a nationwide emphasis on screening and detection. With the widespread use of the prostate-specific antigen (PSA), prostate cancer screening effectively detects localized prostate cancer. However, recent reports have identified a significant proportion of prostate cancer in men with low PSA levels. Many of these cancers are higher-grade malignancies. Consequently, PSA may function more effectively as a screening tool when applied over a continuum that is associated with degree of risk, rather than a binary measure. Other markers are currently being investigated. Ideally, a marker will identify the malignancy that is a clinical threat, thereby avoiding intervention for indolent disease. Prevention strategies may be employed for higher-risk patients, and these strategies eventually may be tailored to genetic or other risks.     

Finasteride improves the sensitivity of digital rectal examination for prostate cancer detection

PURPOSE: Men undergoing screening for prostate cancer are recommended to undergo digital rectal examination and prostate specific antigen measurement. We previously presented data from the Prostate Cancer Prevention Trial indicating that finasteride improves the performance characteristics of prostate specific antigen for cancer detection. In the current study we report the impact of finasteride on digital rectal examination sensitivity and specificity. MATERIALS AND METHODS: We examined the sensitivity and specificity of digital rectal examination in Prostate Cancer Prevention Trial subjects receiving finasteride or placebo who underwent prostate biopsy, had prostate specific antigen measurement and digital rectal examination within 1 year before biopsy and were on treatment at biopsy. RESULTS: Of 9,423 men in the finasteride group 4,579 and 5,112 of 9,459 in the placebo group met study evaluation requirements. Of 4,579 men in the finasteride group 695, including 264 with Gleason 7 or greater and 81 with Gleason 8 or greater, and 1,111 of 5,112 in the placebo group, including 240 with Gleason 7 or greater and 55 with Gleason 8 or greater, were diagnosed with prostate cancer. In men in the placebo and finasteride groups digital rectal examination sensitivity was greater for detecting higher grade tumors. The sensitivity of digital rectal examination was significantly greater for cancer detection in men receiving finasteride than placebo (21.3% vs 16.7%, p=0.015). Digital rectal examination sensitivity was also greater for detecting high grade (Gleason 7 or greater and 8 or greater) cancers in men receiving finasteride but this did not attain statistical significance. Digital rectal examination specificity was similar in men receiving finasteride or placebo. CONCLUSIONS: Finasteride significantly improves prostate cancer detection with digital rectal examination.     

Clinical validation of IsoPSA,a single parameter,structure-focused assay for improved detection of prostate cancer: A prospective,multicenter study

BackgroundIsoPSA is a blood-based test that assesses prostate cancer (CaP) risk by partitioning and detecting cancer-specific structural isoforms of prostate specific antigen (PSA) with an aqueous 2- phase system.ObjectiveTo validate the diagnostic performance of IsoPSA for High-Grade CaP and Any CaP risk on biopsy in men age ≥ 50 with total PSA ≥ 4 ng/ml.Design, Setting, and ParticipantsProspective, multicenter study of 888 men scheduled for prostate biopsy at 8 academic and community sites between August 2015 and August 2020.InterventionIsoPSA test.Outcome Measurements and Statistical AnalysisReceiver operating characteristic and likelihood ratio analysis used to validate diagnostic performance for previously established IsoPSA Index cutoffs for High-Grade CaP (Gleason Score ≥ 7) and Any CaP (Gleason Score ≥ 6), compare IsoPSA to total PSA and % free PSA, and evaluate subgroups (total PSA 4–10 ng/ml, total PSA > 10 ng/ml, biopsy naïve, prior negative biopsy).Results and LimitationsThe disease prevalence was 35.6% (High-Grade CaP) and 58.9% (Any CaP). The area under the receiver operating characteristic curve was 0.783 (High-Grade CaP) and 0.770 (Any CaP). IsoPSA outperformed total PSA and % free PSA on area under the receiver operating characteristic curve, specificity, positive and negative predictive value at similar sensitivity. Using selected IsoPSA Index cutoffs, an estimated 46% (High-Grade CaP) and 42% (Any CaP) of biopsies could be avoided in low-risk patients. IsoPSA displayed statistically informative likelihood ratio-based predictive characteristics. IsoPSA maintained accuracy in clinically relevant subgroups.ConclusionsIsoPSA diagnostic performance and predictive value is validated for High-Grade CaP and Any CaP in men age ≥ 50 with total PSA ≥ 4 ng/ml undergoing diagnostic biopsy. IsoPSA outperforms total and % free PSA in discriminating the risk of prostate cancer on biopsy.Patient SummaryIsoPSA has the potential to reduce unnecessary biopsies and improve the risk-benefit ratio for CaP early detection.     

Prevalence of undiagnosed prostate cancer in men with erectile dysfunction

OBJECTIVE: To explore the prevalence of prostate cancer in men presenting with erectile dysfunction (ED). PATIENTS AND METHODS: In a prospective study, 127 men with ED of at least 6 months duration underwent screening for prostate cancer using prostate specific antigen (PSA) and a digital rectal examination (DRE). Men with a high PSA level (> 4 ng/mL) had sextant biopsies taken under sedoanalgesia. The serum testosterone level was measured in all the men. RESULTS: Twenty-six men were aged < 50 years and all had a normal PSA level; of 101 men aged > 50 years, 20 had an abnormal PSA. The detection rate for prostate cancer using PSA and DRE was 5%, which was not significantly higher than in the general population. All the detected cancers were clinically significant (> T2a, Gleason grade > 4). Two of the five men diagnosed with prostate cancer were Afro-Caribbean. Of the 127 men, 31% had a low serum testosterone level, but there was no association between testosterone and PSA levels. CONCLUSIONS: Prostate cancer is no more common in men with ED than in the normal male population. Therefore, routine screening for prostate cancer in men with ED is not indicated.     

hK2 and free PSA, a prognostic combination in predicting minimal prostate cancer in screen-detected men within the PSA range 4-10 ng/ml

OBJECTIVES: The purpose of screening for prostate cancer is to decrease the disease-specific mortality. However not every screen-detected prostate cancer is a threat to the patient's life. The risk of overdetection and subsequent overtreatment in prostate cancer has been recognised. The purpose of this investigation was to evaluate the role of tumour markers total PSA, free PSA, and hK2, and their combinations in predicting minimal prostate cancer. METHODS: Within the European Randomized Study of Screening for Prostate Cancer (ERSPC), section Rotterdam, The Netherlands, prebiopsy serum samples were analysed for 100 selected men who underwent a radical prostatectomy for their screen-detected prostate cancer. All had a PSA value between 4 and 10 ng/ml prior to diagnosis. Minimal prostate cancer is defined as organ confined, Gleason score 相似文献