M1 prostate cancer with a serum level of prostate-specific antigen less than 10 ng/mL

BACKGROUND: M1 prostate cancer, which is invasive, is usually associated with a serum level of prostate-specific antigen (PSA) greater than 10 ng/mL, but cases are occurring where the serum PSA level is less than this. The present study investigated the clinical and pathologic characteristics of these cases of M1 prostate cancer. METHODS: Between April 1989 and March 1998, 167 cases of M1 prostate cancer were diagnosed by transrectal needle biopsy and eight of these with a serum PSA level less than 10 ng/mL were investigated. The patients' ages ranged from 57 to 79 years (median, 73) and the serum PSA levels ranged from less than 4.0 to 9.8 ng/mL. In all cases except one, the distal metastasis was to bones only. All cases had received hormonal therapy as the initial therapy. Immunostaining of PSA, chromogranin A, neuron-specific enolase, carcinoembryonic antigen and vimentin were performed in five of the eight cases. RESULTS: Four cases were poorly differentiated, two were undifferentiated, one was a mixture of poorly differentiated and undifferentiated and one case was moderately differentiated. Of the five cases in the immunohistochemical study, three cases with an undifferentiated carcinoma component showed negative staining reactions for PSA and all cases were positive for carcinoembryonic antigen. Four of the patients died of prostate cancer. In two of these four cases, hormonal therapy was ineffective, but systemic chemotherapy and irradiation therapy had been moderately effective. The overall 3-year survival rate was 33.3%. CONCLUSIONS: The cases of M1 prostate cancer with a serum PSA less than 10 ng/mL are almost always poorly differentiated or undifferentiated and have a poor prognosis compared with the usual M1 prostate cancer. Because hormonal therapy is ineffective in these cases, systemic chemotherapy and irradiation therapy should be chosen as the initial therapy.     

Under diagnosis and over diagnosis of prostate cancer in a screening population with serum PSA 2 to 10 ng/ml

PURPOSE: Since the implementation of widespread serum total prostate specific antigen based screening, the risk of prostate cancer over diagnosis has become a concern. We evaluated the amount of possible over and under diagnosis of prostate cancer in an asymptomatic screening population with a total prostate specific antigen of 2.0 to 3.9 (lower range) and 4.0 to 10.0 ng/ml (higher range). MATERIALS AND METHODS: A total of 680 patients with prostate cancer were included. Possible over diagnosis was defined as Gleason score less than 7, pathological stage pT2a and negative surgical margins. Under diagnosis was defined as pathological stage pT3 or greater, or positive surgical margins. Furthermore, insignificant tumors according to the Epstein criteria were evaluated in a small subset of patients for whom cancer volume information was available. RESULTS: In the lower and higher total prostate specific antigen ranges there was an over diagnosis rate of 19.7% and 16.5%, and an under diagnosis rate of 18.9%* and 36.7%, respectively (p<0.05). In the prostate specific antigen range of 2.0 to 10.0 ng/ml combined the rates of over and under diagnosis were 17.6% and 30.3%, respectively. In addition, 8.7% of tumors with total prostate specific antigen 2.0 to 10.0 ng/ml met the Epstein criteria for insignificance. CONCLUSIONS: These data show that the reported estimates of over diagnosis in the low total prostate specific antigen group are exaggerated in a screening population. Using our criteria prostate cancer under diagnosis occurs more frequently than over diagnosis in the total prostate specific antigen range of 4.0 to 10 ng/ml.     

晚期前列腺癌内分泌治疗后血清PSA、f-PSA含量的变化

目的探讨前列腺癌(PCa)患内分泌治疗后前列腺特异抗原(PSA)、游离前列腺特异抗原与总前列腺特异抗原比值(f／tPSA)变化的临床意义。方珐测定PCa患内分泌治疗前及治疗后1、3、6个月血清PSA、游离前列腺特异抗原(f-PSA)变化。砖杲治疗后1个月与治疗前相比血清PSA下降明显，治疗后6个月较治疗后1个月血清PSA下降亦有显意义；治疗后患血清f-PSA水平明显下降。f／tPSA值的变化无显意义。结论血清PSA、f-PSA可作为判断PCa内分泌治疗效果的标准．如血清PSA、f-PSA复又升高提示肿瘤复发。     

Prostate-specific antigen cut-off point of 2.5 ng/mL and increasing the number of prostate biopsies results in the detection of curable prostate cancer even in Japanese population

AIM: There is a trend for the cut-off point of Prostate-specific antigen (PSA) to be lower and the number of biopsies to be increased for detecting prostate cancer. I divided patients who visited my institution for prostate biopsy into 3 groups based on the time of examination. The results were evaluated retrospectively. METHODS: The three groups were: group A, PSA cut-off point of 4.0 ng/mL and sextant biopsy; group B, 2.5 ng/mL and 12 core biopsies; and group C, 2.5 ng/mL and saturation biopsy. I evaluated the rates of cancer detection, localized cancer, T1c, high grade cancer, major complications, insignificant cancer and the pain scores, and compared biopsy number and cancer detection rates with PSA range. Only the patients with T1c and PSA 2.6-10.0 ng/mL were evaluated about high grade cancer and insignificant cancer rates. RESULTS: Cancer detection rates, localized cancer rates and T1c rates were significantly high in group C. There were no significant differences in the high grade cancer rates, major complication rates and the insignificant cancer rates. A comparison between biopsy number and cancer detection rates was significantly high in the saturation biopsy group with PSA 4.1-10.0 ng/mL. CONCLUSION: A PSA cut-off point of 2.5 ng/mL and increasing the number of biopsies results in the increased detection of localized prostate cancer. The insignificant cancer rate, the high grade cancer rate and the complication rate were not significantly different among the groups. I recommend a PSA cut-off point of 2.5 ng/mL and an increased number of biopsies, saturation biopsy particularly in cases with PSA 4.1- 10.0 mg/mL.     

Tumour markers for managing men who present with metastatic prostate cancer and serum prostate-specific antigen levels of <10 ng/mL

OBJECTIVE: To define immunohistochemical features of the primary cancers that might help in the differential diagnosis and monitoring of treatment in men presenting with metastatic prostate cancer and low serum levels of prostate-specific antigen (PSA), who can be difficult to diagnose and manage. PATIENTS AND METHODS: Paraffin blocks of prostate biopsies were obtained for 33 patients presenting with untreated metastatic prostate cancer and serum PSA levels of <10 ng/mL. Sections were immunostained for PSA, prostatic acid phosphatase (PAP), prostate-specific membrane antigen (PSMA), androgen receptor (AR), chromogranin A and CD 56. RESULTS: The combined Gleason scores were 8-10 in 25 men (76%) and 6 or 7 in the other eight (24%). Morphologically, there were no neuroendocrine features. PSA immunostaining was equivocal in 12 (36%) cases and in a further 19 (58%) was strong but focal and could be missed on biopsy sampling. PSMA was expressed in 90% of cases, and staining was widely distributed in nine of the 12 in which PSA staining was equivocal. There was strong AR expression in 30 (91%) cases and it was present in areas where PSA was absent. CONCLUSION: In this patient group, immunohistochemical assessments of PSMA and AR are potentially useful as diagnostic markers.     

Predictors of prostate cancer on repeat prostatic biopsy in men with serum total prostate-specific antigen between 4.1 and 10 ng/mL

OBJECTIVES: We determine whether the different molecular forms of prostate-specific antigen (PSA) and other PSA variables can predict prostate cancer in men undergoing repeat prostate needle biopsy. METHODS: Between 1997 and 2001, repeat biopsy was performed in 97 patients who had undergone prior negative prostate biopsy. The ability of total PSA (tPSA), complexed PSA (cPSA), free PSA (fPSA), free-to-total PSA (fPSA/tPSA), free-to-complexed PSA (fPSA/cPSA), complexed-to-total PSA (cPSA/tPSA), tPSA density (tPSAD), cPSA density (cPSAD), transition zone tPSA density (tPSATZ) and transition zone cPSA density (cPSATZ) was assessed by univariate and multivariate analyzes as well as receiver operating characteristics (ROC) curves. RESULTS: Prostate cancer on repeat biopsy was detected in 24% of subjects (23 of 97) who had a negative initial biopsy. The PSA parameters cut-off to ensure a 96% sensitivity of cancer detection, were 29% using fPSA/tPSA, 32% using fPSA/cPSA, 0.18 ng/mL/cc using tPSATZ and 0.16 ng/mL/cc using cPSATZ. The fPSA/tPSA would have prevented 32% of negative biopsies, the fPSA/cPSA 28%, the tPSATZ 23% and the cPSATZ 30%. ROC curve analysis fPSA/tPSA, fPSA/cPSA ratios, tPSATZ and cPSATZ were significantly better predictors of repeat biopsy results than tPSA or cPSA, but there was no significant difference in the ROC curves among these four PSA parameters. In the multivariate logistic regression analysis these four PSA parameters were significant predictors for cancer detection in the repeat biopsy group (P < 0.001). CONCLUSION: fPSA/tPSA ratio, fPSA/cPSA ratio, tPSATZ and cPSATZ enhance the specificity of PSA testing compared to tPSA or cPSA when determining which patients should undergo repeat biopsy.     

Value of prostate specific antigen α1-antichymotrypsin complex for the detection of prostate cancer in patients with a PSA level of 4.1–10.0ng/mL: Comparison with PSA-related parameters

BACKGROUND: The aim of the present study was to evaluate the usefulness of prostate specific antigen alpha1-antichymotrypsin complex (PSA-ACT) in the differential diagnosis of prostate cancer in patients with a PSA level of 4.1-10.0 ng/mL compared to several PSA- and PSA-ACT-related parameters. METHODS: Serum samples were obtained from 103 patients with no evidence of malignancy on biopsy and 29 with histologically confirmed prostate cancer. All patients had pretreatment serum PSA levels between 4.0 and 10.0 ng/mL. The different forms of serum PSA, including total PSA (tPSA), free PSA (fPSA) and PSA-ACT were measured using immunofluorometric techniques with different monoclonal antibodies against PSA and ACT. Furthermore, tPSA and PSA-ACT densities of the whole prostate (PSAD and ACTD, respectively) and the f-to-tPSA and the f-to-PSA-ACT ratios (F/T ratio and F/ACT ratio, respectively) were calculated. RESULTS: The differences between patients with prostate cancer and benign prostatic disease were significant with respect to all six parameters examined in this study. Analysis of receiver operating characteristics revealed that the areas under the curve for PSA-ACT, ACTD and the F/ACT ratio were larger than those for tPSA, PSAD and the F/T ratio, respectively. However, there were no significant differences in discrimination between benign and malignant diseases among these six parameters. CONCLUSIONS: In patients who have an intermediate serum PSA level, PSA-ACT and its associated parameters may not be significantly superior in the differential diagnosis between prostate cancer and benign prostatic diseases compared to tPSA and its traditional relatives.     

前列腺癌患者血清中铜、锌与铜/锌比值的变化及意义

目的探讨血清铜、锌含量与前列腺癌之间的关系，并将其与血清前列腺特异性抗原（PSA）比较，探讨其在前列腺癌诊断中价值比较。方法采用原子吸收分光光度法测定76例前列腺癌患者、125例前列腺增生患者和191例健康男性的血清铜、锌含量。结果前列腺癌组血清锌明显低于健康对照组，血清铜和铜/锌比值明显高于健康对照组（P〈0.05）。前列腺癌组血清铜及铜/锌比值与前列腺增生组比较未见显著性差异;前列腺癌组血清锌低于前列腺增生组（P〈0.05）。前列腺增生组血清锌与健康对照组比较未见显著性差异;前列腺增生组血清铜和铜/锌比值高于健康对照组（P〈0.05）。PSA在4.0-10.0ng/ml灰色区域的前列腺癌组，血清锌ROC-AUC（receiver operator characteristic curve-area under curve）为66%，高于PSA的ROC-AUC。结论血清铜、铜/锌比值升高及血清锌降低可能是前列腺癌发生的危险因素，血清锌在PSA（4.0～10.0）ng/ml灰色区域的前列腺癌诊断效率高于PSA，其可能为前列腺癌的诊断提供有价值的指标。     

超声造影经直肠前列腺靶向穿刺活检术在PSA 4~10 ng/ml患者中的作用

目的探讨超声造影经直肠前列腺靶向穿刺活检术（CETRUS-PB）在PSA 4~10 ng/ml患者中的作用。 方法2016年1月至2018年12月,番禺中心医院82例泌尿外科收治的PSA 4~10 ng/ml的患者根据自愿原则被分入系统性经直肠超声前列腺穿刺活检术组（STRUS-PB）和CETRUS-PB组,比较两组穿刺的效率、视觉模拟疼痛评分（VAS）以及并发症。 结果CETRUS-PB与STRUS-PB组在PSA 4~10 ng/ml的患者中穿刺阳性率差异无统计学意义（P=0.147）,两组穿刺针数、Gleason评分以及视觉疼痛评分的比较差异有统计学意义（P<0.001）,两组均未出现严重并发症。 结论在PSA 4~10 ng/ml患者中,CETRUS-PB不能显著提高穿刺阳性率,但可以提高穿刺的精准度,减少穿刺针数,减轻痛苦。     

正常血清PSA进展期前列腺癌1例报告并文献复习

目的:探讨正常血清PSA进展期前列腺癌患者的诊断及治疗方法,提高前列腺癌的诊疗水平。方法:回顾性分析2010年收治的1例正常血清PSA进展期前列腺癌患者临床资料,结合相关文献,讨论正常血清PSA进展期前列腺癌的诊断及治疗方法。结果:患者血清PSA水平一直处于正常水平,经病理学检查证实为前列腺癌,临床分期为T4N0M0,行前列腺去势术+抗雄激素治疗,现已无进展生存15个月。结论:正常血清PSA进展期前列腺癌多系特殊病理类型的前列腺癌,预后相对较差。在进行PSA筛查时,需综合考虑f/tPSA比值;术后随诊时需定期进行影像学检查,以了解有无疾病进展;治疗上除采取内分泌治疗外,必要时宜早期采用放疗及化疗。     

8点及12点前列腺穿刺活检诊断前列腺癌的价值比较研究

目的比较8点及12点前列腺穿刺活检诊断前列腺癌的价值,分析前列腺特异性抗原(PSA)、前列腺特异性抗原密度(PSAD)及前列腺体积(PV)对前列腺癌检出率(PCDR)的影响。方法回顾性分析260例因PSA异常增高而接受首次直肠超声引导下前列腺穿刺活检的患者相关资料,其中132例患者接受8点穿刺,128例患者接受12点穿刺。结果依据PSA、PV、PSA与PV及PSAD,患者被进一步分组。8点及12点的总的PCDR没有显著的差异,在PV≥45mL、PSA≥10ng/mL且PV≥45mL及0.15ng/(mL·cm3)≤PSAD≤0.25ng/(mL·cm3)组中,12点的PCDR明显高于8点。结论 8点及12点前列腺穿刺总的PCDR没有显著区别(P0.05),但在PV较大同时PSA较高或者PSAD处于中等大小时(0.15~0.25)ng/(mL·cm3),12点的PCDR明显高于8点(P均0.05)。     

Preoperative serum prostate specific antigen levels between 2 and 22 ng./ml. correlate poorly with post-radical prostatectomy cancer morphology: prostate specific antigen cure rates appear constant between 2 and 9 ng./ml.

PURPOSE: Serum prostate specific antigen (PSA) is widely used as a guide to initiate prostatic biopsies and to follow men older than 50 years old with and without prostate cancer. However, benign prostatic hyperplasia (BPH) is a common cause of serum PSA values between 2 and 10 ng./ml. A better understanding of the relationships among serum PSA, prostate cancer and BPH is important. MATERIALS AND METHODS: A total of 875 men underwent radical prostatectomy at our institution between December 1984 and January 1997. Of these men 784 had a serum PSA of 2 to 22 ng./ml., including 579 with the largest cancer located in the peripheral zone of the prostate. Of the 579 men 406 had serum PSA followups for greater than 3 years after radical prostatectomy. We examined Pearson correlations (R2) between preoperative serum PSA, and the volume of Gleason grades 4/5 and 3 to 1 cancer in 784 men, separating peripheral zone from transition zone cancers. We used broken line regression with break points of 7 and 9 ng./ml. preoperative PSA to summarize the relationship of each PSA doubling to 5 different morphological variables in 579 men with peripheral zone cancer. A 9 ng./ml. break point was used for prostate weight. Trend summaries with a local regression line for the relationships between 6 morphological variables and PSA were superimposed on full scatterplots of the 579 men with PSA less than 22 ng./ml. Cox proportional hazard models were used to examine 5-year PSA failure-free probabilities based on 406 men with minimal PSA followups greater than 3 years at break points of 7 to 9 ng./ml. PSA. RESULTS: Pearson correlation between cancer volume and preoperative serum PSA in 875 men was weak (r2 = 0.27) and driven by large cancers with serum PSA greater than 22 ng./ml. For peripheral zone cancer the overall R2 x 100 for 641 men with low and high grade cancer was 10% and only 3% for low grade cancer, that is almost no PSA produced by these peripheral zone cancers enters the serum. All morphological variables changed at rates of doubtful medical significance below a PSA of 7 to 9 ng./ml. but at rates that were significantly worse above 9 ng./ml. R2 for these relationships was never greater than 15%. Large individual morphological variations at all levels of PSA emphasize the serious limitation of PSA as a predictor of prostate cancer morphology. Below 9 ng./ml. prostate weight increased by 21% for each doubling of PSA but above 9 ng./ml. the increase was only 4.8%. CONCLUSIONS: Preoperative serum PSA has a clinically useless relationship with cancer volume and grade in radical prostatectomy specimens, and a limited relationship with PSA cure rates at preoperative serum PSA levels of 2 to 9 ng./ml. Trend summaries for prostate weight on broken line regression showed that below 9 ng./ml. BPH is a strong contender for the cause of PSA elevation, constituting the primary cause of the over diagnosis of prostate cancer.     

Pre-operative percent free PSA predicts clinical outcomes in patients treated with radical prostatectomy with total PSA levels below 10 ng/ml

INTRODUCTION: To evaluate the association of total prostate specific antigen (T-PSA) and percent free PSA (%F-PSA) with prostate cancer outcomes in patients treated with radical prostatectomy (RP). METHODS: Pre-operative serum levels of T-PSA and F-PSA were prospectively measured in 402 consecutive patients treated with RP for clinically localized prostate cancer who had T-PSA levels below 10 ng/ml. RESULTS: T-PSA was not associated with any prostate cancer characteristics or outcomes. Lower %F-PSA was significantly associated with higher percent positive biopsy cores, extracapsular extension, seminal vesicle involvement, lympho-vascular invasion, perineural invasion, positive surgical margins, and higher pathologic Gleason sum. When adjusted for the effects of standard pre-operative features, lower %F-PSA significantly predicted non-organ confined disease, seminal vesicle involvement, lympho-vascular invasion, and biochemical progression. %F-PSA did not retain its association with biochemical progression after adjusting for the effects of standard post-operative features. Based on data from 22 patients with biochemical progression, lower %F-PSA was correlated with shorter T-PSA doubling time after biochemical progression (rho = 0.681, p = 0.010). %F-PSA was lower in patients who failed salvage radiation therapy (p = 0.031) and in patients who developed distant cancer metastases compared to patients who did not (p < 0.001). CONCLUSIONS: Pre-operative T-PSA is not associated with prostate cancer outcomes after RP when levels are below 10 ng/ml. In contrast, pre-operative %F-PSA is associated with adverse pathologic features, biochemical progression, and features of aggressive disease progression in patients treated with RP and T-PSA levels below 10 ng/ml. %F-PSA may improve pre-operative predictive models for predicting clinical outcomes of patients diagnosed with prostate cancer nowadays.     

Measurement of prostate specific antigen complexed to α1-antichymotrypsin to avoid unnecessary biopsy in patients with serum prostate specific antigen levels 4–20 ng/mL

AIM: To investigate whether measuring prostate specific antigen complexed to alpha1-Antichymotrypsin (PSA-ACT) can increase sensitivity and specificity in detecting prostate cancer. METHODS: In this prospective study, we measured serum total PSA, PSA-ACT, free PSA, prostate volume and transition zone volume on 210 patients with total PSA level of 4-20 ng/mL. From fitted curves between positive predictive values for prostate cancer and age, prostate volume, transition zone volume, total PSA, PSA-ACT or F/T ratio, each function predicting prostate cancer was determined. Relative probabilities for prostate cancer (RPpca) which were defined by combined functions of age, F/T ratio, prostate volume or transition zone volume, and total PSA or PSA-ACT were calculated. Furthermore, using logistic regression, analysis was performed to determine the probability of prostate cancer. Receiver-operating characteristic analysis was performed to clarify the areas under the curve (AUC) for conventional single parameters, RPpca and logistic regression probability. RESULTS: F/T ratio showed the largest AUC among conventional parameters. The AUC of RPpca was larger than those of F/T ratio and logistic regression probability. RPpca using the functions of age, transition zone volume, PSA-ACT and F/T ratio showed the largest AUC and highest specificity at sensitivity 95% level, however, specificities at sensitivity 90% and 85% were identical to those of RPpca using the functions of age, prostate volume, total PSA and F/T ratio. CONCLUSIONS: RPpca using the functions of age, transition zone volume, PSA-ACT and F/T ratio was the best way to detect prostate cancer, however, the usefulness of PSA-ACT appears limited, considering the cost.     

Influence of prostate volume and percent free prostate specific antigen on prostate cancer detection in men with a total prostate specific antigen of 2.6 to 10.0 ng/ml

PURPOSE: Percent free prostate specific antigen and prostate specific antigen density have been independently shown to increase the specificity of prostate cancer screening in men with prostate specific antigen levels between 4.1 and 10.0 ng/ml. Recent data suggest the total prostate specific antigen cutoff for performing a biopsy should be 2.6 ng/ml. We assessed the influence of percent free prostate specific antigen and prostate volume on cancer detection in men with a prostate specific antigen between 2.6 and 10.0 ng/ml. MATERIALS AND METHODS: From 1991 to 2005 all transrectal ultrasound guided prostate biopsies (5,587) for abnormal digital rectal examination and/or increased age specific prostate specific antigen were evaluated. A total of 1,072 patients with a prostate specific antigen between 2.6 and 10.0 ng/ml and any percent free prostate specific antigen were included in study. The cancer detection rate was calculated for each percent free prostate specific antigen/volume stratum. RESULTS: Prostate cancer was detected in 296 patients (27.6%). The mean age and prostate specific antigen of the patients with benign pathology and prostate cancer were similar. Mean percent free prostate specific antigen was 17.5% and 14.1% (p>0.05), and the mean volume was 62.0 and 46.0 cc (p=0.001), respectively. The strongest risk factors for a positive biopsy were percent free prostate specific antigen (odds ratio 0.004, p<0.001), volume (OR 0.977, p<0.001) and digital rectal examination (OR 1.765, p=0.007), but not total prostate specific antigen (p=0.303). When stratified by volume and percent free prostate specific antigen, distinct risk groups were identified. The probability of detecting cancer inversely correlated with prostate volume and percent free prostate specific antigen. CONCLUSIONS: In men with prostate specific antigen levels between 2.6 and 10.0 ng/ml, the probability of detecting cancer was inversely proportional to prostate volume and percent free prostate specific antigen. This table may assist in predicting patient risk for harboring prostate cancer.     

Development of a new nomogram for predicting the probability of a positive initial prostate biopsy in Japanese patients with serum PSA levels less than 10 ng/mL

Objectives:   Although several nomograms for prostate cancer detection have been developed for Western populations, the models constructed on Japanese data would be more useful for the Japanese population because of various differences between Western and Asian populations. We previously developed a model for predicting the probability of a positive initial prostate biopsy using clinical and laboratory data from Japanese males. In the present study, a predictive model for Japanese males with a prostate-specific antigen (PSA) < 10 ng/mL was developed to guide decision-making for prostate biopsies.
Methods:   The age, total PSA level, free to total PSA ratio, prostate volume, and the digital rectal examination findings of 1037 Japanese males with a PSA < 10 ng/mL undergoing initial prostate biopsy as part of individual screening were analyzed. For study validation, 20% of these data was randomly reserved. Logistic regression analysis estimated relative risk, 95% confidence intervals, and P -values.
Results:   Age and the independent predictors of a positive biopsy result (elevated PSA, decreased free to total PSA ratio, small prostate volume, and abnormal digital rectal examination findings) were used to develop a predictive nomogram. The area under the receiver operating characteristic curve was significantly higher for the model (73.0%) than for PSA alone (55.0%). If externally validated, the use of this nomogram could reduce unnecessary biopsies by 26% and overall prostate biopsies by 7.8%.
Conclusions:   This predictive nomogram could provide more precise risk-analysis information for individual Japanese patients with PSA levels less than 10 ng/mL and may help to identify patients who need a prostate biopsy.     

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

To clarify the recent trends in prostate-specific antigen （PSA） distribution in men in Japan, we analyzed the PSA distributions of men undergoing PSA-based population screening. We summarized the annual individual data of PSA-based population screening in Kanazawa, Japan, from 2000 to 2011, and analyzed baseline serum PSA values of the participants at the first population screening. Serum PSA distributions were estimated in all participants and those excluding prostate cancer patients according to age. From 2000 to 2011, 19 620 men participated aged 54-69 years old in this screening program. Mean baseline serum PSA level of all participants at the first screening was 2.64 ng m1-1 in 2000, and gradually decreased to approximately 1.30 ng ml-I in 2006. That of participants excluding prostate cancer patients was 1.46 ng m1-1 in 2000, and there was no remarkable change during the study period. The 95t＂ percentiles in the participants excluding prostate cancer patients detected at the first population screening of men aged 54-59, 60-64, and 65-69 years old were 2.90, 3.60, and 4.50 ng m1-1, respectively. After the commencement of population screening, the proportion of prostate cancer patients with high serum PSA levels decreased. However, there were no changes in serum PSA levels in men without prostate cancer. Age-specific PSA reference level of men without prostate cancer in Japan was similar to that in China and Korea.