Cost-effectiveness of prostate cancer screening: a simulation study based on ERSPC data

BACKGROUND

The results of the European Randomized Study of Screening for Prostate Cancer (ERSPC) trial showed a statistically significant 29% prostate cancer mortality reduction for the men screened in the intervention arm and a 23% negative impact on the life-years gained because of quality of life. However, alternative prostate-specific antigen (PSA) screening strategies for the population may exist, optimizing the effects on mortality reduction, quality of life, overdiagnosis, and costs.

METHODS

Based on data of the ERSPC trial, we predicted the numbers of prostate cancers diagnosed, prostate cancer deaths averted, life-years and quality-adjusted life-years (QALY) gained, and cost-effectiveness of 68 screening strategies starting at age 55 years, with a PSA threshold of 3, using microsimulation modeling. The screening strategies varied by age to stop screening and screening interval (one to 14 years or once in a lifetime screens), and therefore number of tests.

RESULTS

Screening at short intervals of three years or less was more cost-effective than using longer intervals. Screening at ages 55 to 59 years with two-year intervals had an incremental cost-effectiveness ratio of $73000 per QALY gained and was considered optimal. With this strategy, lifetime prostate cancer mortality reduction was predicted as 13%, and 33% of the screen-detected cancers were overdiagnosed. When better quality of life for the post-treatment period could be achieved, an older age of 65 to 72 years for ending screening was obtained.

CONCLUSION

Prostate cancer screening can be cost-effective when it is limited to two or three screens between ages 55 to 59 years. Screening above age 63 years is less cost-effective because of loss of QALYs because of overdiagnosis.

Treatment of local-regional prostate cancer detected by PSA screening: benefits and harms according to prognostic factors

Background:

Men with screen-detected prostate cancer can choose to undergo immediate curative treatment or enter into an expectant management programme. We quantified how the benefits and harms of immediate treatment vary according to the prognostic factors of clinical T-stage, Gleason score, and patient age.

Methods:

A microsimulation model based on European Randomized Study of Screening for Prostate Cancer data was used to predict the benefits and harms of immediate treatment versus delayed treatment of local–regional prostate cancer in men aged 55–74 years. Benefits included life-years gained and reduced probability of death from prostate cancer. Harms included lead time and probability of overdiagnosis.

Results:

The ratio of mean lead time to mean life-years gained ranged from 1.8 to 31.2, and the additional number of treatments required per prostate cancer death prevented ranged from 0.3 to 11.6 across the different prognostic groups. Both harm–benefit ratios were lowest, most favourable, for men aged 55–59 years and diagnosed with moderate-risk prostate cancer. Ratios were high for men aged 70–74 years regardless of clinical T-stage and Gleason score.

Conclusion:

Men aged 55–59 years with moderate-risk prostate cancer are predicted to derive greatest benefit from immediate curative treatment. Immediate treatment is least favourable for men aged 70–74 years with either low-risk or high-risk prostate cancer.

Importance of prostate volume in the European Randomised Study of Screening for Prostate Cancer (ERSPC) risk calculators: results from the prostate biopsy collaborative group

OBJECTIVES

To compare the predictive performance and potential clinical usefulness of risk calculators of the European Randomized Study of Screening for Prostate Cancer (ERSPC RC) with and without information on prostate volume.

METHODS

We studied 6 cohorts (5 European and 1 US) with a total of 15,300 men, all biopsied and with pre-biopsy TRUS measurements of prostate volume. Volume was categorized into 3 categories (25, 40, and 60 cc), to reflect use of digital rectal examination (DRE) for volume assessment. Risks of prostate cancer were calculated according to a ERSPC DRE-based RC (including PSA, DRE, prior biopsy, and prostate volume) and a PSA + DRE model (including PSA, DRE, and prior biopsy). Missing data on prostate volume were completed by single imputation. Risk predictions were evaluated with respect to calibration (graphically), discrimination (AUC curve), and clinical usefulness (net benefit, graphically assessed in decision curves).

RESULTS

The AUCs of the ERSPC DRE-based RC ranged from 0.61 to 0.77 and were substantially larger than the AUCs of a model based on only PSA + DRE (ranging from 0.56 to 0.72) in each of the 6 cohorts. The ERSPC DRE-based RC provided net benefit over performing a prostate biopsy on the basis of PSA and DRE outcome in five of the six cohorts.

CONCLUSIONS

Identifying men at increased risk for having a biopsy detectable prostate cancer should consider multiple factors, including an estimate of prostate volume.

Under- and upgrading of prostate cancer after radical prostatectomy in a screening setting

105

Background: It has been well established that there is an upward drift in assigned Gleason score (GS) to prostate cancer (PC) biopsies. However, few studies have examined the concordance between biopsy GS and pathological GS after radical prostatectomy (RP) in a screening setting over time. We assessed the proportion of under and upgrading of PC after RP by comparing the prevalence screen with the incidence screens from the European Randomized Study of Screening for Prostate Cancer (ERSPC), section Rotterdam.

Methods: From 1993 to 1999, a total of 42.376 men identified from population registries in the Rotterdam region (55-74 yrs) were randomized into a screening or control arm. Men with PSA ≥3.0 ng/ml were recommended for sextant prostate biopsy, which were lateralized since 1996. The screening interval was 4 yrs. Men with screen-detected PC, who underwent RP within 1 yr, were eligible for this study.

Results: In all, biopsy and pathological GS were known for 639 men who underwent RP. Of these RPs, 405 were performed between 1994 and 2000 (prevalence screen) whereas 235 cases were performed between 1998 and 2008 (incidence screens). In the prevalence screen, 49.8% of the biopsy GS matched the pathological GS ( Table ). This percentage improved to 58.3% in the incidence screens (p=0.045). The proportion of undergrading after RP was 23.0% in the prevalence screen, which declined to 16.2% in the incidence screens (p=0.049). Upgrading occurred in 27.2% of the cases in the prevalence and 25.5% in the incidence screens (p=0.71).

Conclusions: We have demonstrated an improved concordance between biopsy and pathological GS over time by comparing cancers detected in the prevalence screen with those detected in the incidence screens, which is in line with the upward shift of GS classification over time. In addition, significant less undergrading occurred in the incidence screens. However, one should keep in mind that within this screening program still a quarter of the biopsy GS were upgraded after RP in the incidence screens.

[Table: see text]

[Table: see text]

Prostate cancer incidence and disease-specific survival in men participating in the ERSPC with an initial PSA less than 3.0 ng/mL

7

Background: The European Randomized Study of Screening for Prostate Cancer (ERSPC) applies a prostate- specific antigen (PSA) cut-off >3.0 ng/mL as an indication for biopsy. We analyzed the incidence and disease-specific mortality for prostate cancer (PC) within ERSPC Rotterdam for men with an initial PSA <3.0 ng/ml in a 15-year follow-up period.

Methods: From 1993-1999, a total of 42,376 men identified from population registries in the Rotterdam region (55-74 yrs) were randomized to a screening or control arm. During the first screening round 19,950 men were screened, with biopsies being initially recommended in case of abnormal DRE or PSA >4.0 ng/mL. From 1997 on, solely PSA >3.0 ng/mL was used. The screening interval was 4 yrs. A total of 15,758 men (79%) had an initial PSA <3.0 ng/mL. Follow-up was complete until January 2009.

Results: From 1993-2008, 915 PC cases were diagnosed in 15,758 men (5.8%, median age 62.3 yrs) with an initial PSA <3.0 ng/mL (733 screen detected and 182 interval detected). Median follow-up was 11 yrs. PC incidence increased significantly with higher initial PSA levels (Table). Aggressive PC (clinical stage >T2c, Gleason score >8, PSA >20 ng/mL, positive lymph nodes or metastases at diagnosis) was detected in 65/733 screen detected PC (8.9%) and 102/182 interval detected PC (56.0%). PC death occurred in 23 cases (5 screen detected and 18 interval detected) in the total population (0.15%), with increasing risk in men with higher initial PSA values.

Conclusions: The risk of (aggressive) PC and PC mortality in a screening population with initial PSA <3.0 ng/mL increases significantly with higher PSA levels. The risk of dying of PC is minor in men with initial PSA <1.0 ng/mL. Interval detected PC is more aggressive and has a substantial influence on PC specific mortality.

[Table: see text]

[Table: see text]

A four-kallikrein panel for the prediction of repeat prostate biopsy: data from the European Randomized Study of Prostate Cancer screening in Rotterdam, Netherlands

Background:

Most men with elevated levels of prostate-specific antigen (PSA) do not have prostate cancer, leading to a large number of unnecessary biopsies. A statistical model based on a panel of four kallikreins has been shown to predict the outcome of a first prostate biopsy. In this study, we apply the model to an independent data set of men with previous negative biopsy but persistently elevated PSA.

Methods:

The study cohort consisted of 925 men with a previous negative prostate biopsy and elevated PSA (⩾3 ng ml⁻¹), with 110 prostate cancers detected (12%). A previously published statistical model was applied, with recalibration to reflect the lower positive biopsy rates on rebiopsy.

Results:

The full-kallikrein panel had higher discriminative accuracy than PSA and DRE alone, with area under the curve (AUC) improving from 0.58 (95% confidence interval (CI): 0.52, 0.64) to 0.68 (95% CI: 0.62, 0.74), P<0.001, and high-grade cancer (Gleason ⩾7) at biopsy with AUC improving from 0.76 (95% CI: 0.64, 0.89) to 0.87 (95% CI: 0.81, 0.94), P=0.003). Application of the panel to 1000 men with persistently elevated PSA after initial negative biopsy, at a 15% risk threshold would reduce the number of biopsies by 712; would miss (or delay) the diagnosis of 53 cancers, of which only 3 would be Gleason 7 and the rest Gleason 6 or less.

Conclusions:

Our data constitute an external validation of a previously published model. The four-kallikrein panel predicts the result of repeat prostate biopsy in men with elevated PSA while dramatically decreasing unnecessary biopsies.

The interobserver variability of digital rectal examination in a large randomized trial for the screening of prostate cancer

BACKGROUND

To analyze to what extent the percentage of suspicious digital rectal examination (DRE) findings vary between examiners and to what extent the percentage of prostate cancers (PCs) detected in men with these suspicious findings varies between examiners.

METHODS

In the first screening round of the European Randomized study of Screening for PC (ERSPC) Rotterdam, 7,280 men underwent a PSA-determination and DRE of whom 2,102 underwent prostate biopsy (biopsy indication PSA > or = 4.0 ng/ml and/or suspicious DRE and/or TRUS). Descriptive statistics of DRE-outcome per PSA-range were used to determine the observer variability of six examiners. Because this analysis did not correct properly for other predictors of a suspicious DRE (PSA-level, biopsy indication, TRUS-outcome, prostate volume and age), a logistic regression analysis controlling for these explanatory variables was performed as well.

RESULTS

In 2,102 men biopsied, 443 PCs were detected (PPV = 21%). For all PSA levels the percentage suspicious DRE varied between examiners from 4% to 28% and percentage PC detected in men with a suspicious DRE varied from 18% to 36%. Logistic regression analysis showed that three of six examiners considered DRE significantly more often abnormal than others (ORs 3.48, 2.80, 2.47, P < 0.001). For all examiners the odds to have PC was statistically significantly higher in case of a suspicious DRE (ORs 2.21-5.96, P < 0.05). This increased chance to find PC was not significantly observer-dependent.

CONCLUSIONS

Three of six examiners considered DRE significantly more often suspicious than the others. However, under equal circumstances a suspicious DRE executed by each examiner increased the chance of the presence of PC similarly.

Overdiagnosis and overtreatment of early detected prostate cancer

Early detection of prostate cancer is associated with the diagnosis of a considerable proportion of cancers that are indolent, and that will hardly ever become symptomatic during lifetime. Such overdiagnosis should be avoided in all forms of screening because of potential adverse psychological and somatic side effects. The main threat of overdiagnosis is overtreatment of indolent disease. Men with prostate cancer that is likely to be indolent may be offered active surveillance. Evaluation of active surveillance studies and validation of new biological parameters for risk assessment are expected.

Prediction of Indolent Prostate Cancer: Validation and Updating of a Prognostic Nomogram

PURPOSE

Screening with serum prostate specific antigen testing leads to the detection of many prostate cancers early in their natural history. Statistical models have been proposed to predict indolent cancer. We validated and updated model predictions for a screening setting.

MATERIALS AND METHODS

We selected 247 patients with clinical stage T1C or T2A from the European Randomized Study on Screening for Prostate Cancer who were treated with radical prostatectomy. We validated a nomogram that had previously been developed in a clinical setting. Predictive characteristics were serum prostate specific antigen, ultrasound prostate volume, clinical stage, prostate biopsy Gleason grade, and total length of cancer and noncancer tissue in biopsy cores. Indolent cancer was defined as pathologically organ confined cancer 0.5 cc or less in volume without poorly differentiated elements. Logistic regression was used to update the previous model and examine the contribution of other potential predictors.

RESULTS

Overall 121 of 247 patients (49%) had indolent cancer, while the average predicted probability was around 20% (p <0.001). Effects of individual variables were similar to those found before and discriminative ability was adequate (AUC 0.76). An updated model was constructed, which merely recalibrated the nomogram and did not apply additional predictors.

CONCLUSIONS

Prostate cancers identified in a screening setting have a substantially higher likelihood of being indolent than those predicted by a previously proposed nomogram. However, an updated model can support patients and clinicians when the various treatment options for prostate cancer are considered.

Anxiety and depression after prostate cancer diagnosis and treatment: 5-year follow-up

To document anxiety and depression from pretreatment till 5-year follow-up in 299 men with localized prostate cancer. To assess, if baseline scores were predictive for anxiety and depression at 1-year follow-up. Respondents completed four assessments (pretreatment, at 6 and 12 months, and at 5-year follow-up) on anxiety, depression and mental health. Respondents were subdivided according to therapy (prostatectomy or radiotherapy) and high vs low-anxiety. Pretreatment 28% of all patients were classified as 'high-anxiety'; their average anxiety scores decreased significantly post-treatment, that is towards less anxiety. At all assessments, high-anxiety men treated by prostatectomy reported less depression than high-anxiety men treated by radiotherapy. Of men treated by radiotherapy, 27% reported clinical significant levels of depression while 20% is expected in a general population. The improvement in mental health at 6-months follow-up was statistically significant and clinically meaningful in all respondent groups. Sensitivity of anxiety at baseline as a screening tool was 71% for anxiety and 60% for symptoms of depression. We recommend clinicians to attempt early detection of patients at risk of high levels of anxiety and depression after prostate cancer diagnosis since prevalence is high. STAI-State can be a useful screening tool but needs further development.

Very late local recurrence after surgery for prostate cancer unaccompanied by detectable PSA levels

The possibility and possible aetiology of local prostate cancer (PC) recurrence despite undetectable prostate-specific antigen (PSA) levels are highlighted. A case of a local recurrence 8.5 years after radical prostatectomy for Gleason 3+4 PC is presented. It demonstrates that PC can recur, even after a prolonged period of time (8.5 years), despite undetectable levels (i.e. <0.02 ng/ml) of PSA. In conclusion, the decision to omit digital rectal examination from the follow-up regimens of men with undetectable PSA levels could be justified. In such exceptional cases, however, PC recurrence would be either missed or would only be diagnosed after a considerable delay.

Atrophy in prostate needle biopsy cores and its relationship to prostate cancer incidence in screened men

OBJECTIVES

To evaluate whether the incidence of atrophy reported on sextant biopsies is associated with subsequent prostate cancer detection and to obtain a more thorough analysis of the different categories and extent of atrophy, we performed a review of benign biopsy cores.

METHODS

In the Rotterdam section of the European Randomized Study of Screening for Prostate Cancer, 4117 and 1840 men underwent sextant biopsy in the first and second screening round (4-year interval), respectively. Sextant biopsy was prompted by elevated prostate-specific antigen levels. For review, randomly taken benign sextant biopsies (n = 202) with a follow-up of at least 8 years were chosen.

RESULTS

Before review, atrophy was reported in the biopsies of 11.4% and 8.7% of the first and second round, respectively. The prostate cancer incidence during 8 years of follow-up after an initial diagnosis of atrophy was 10.4%, which was not significantly different than the 12.3% of cancers detected after a benign diagnosis without reference to atrophy. After review, the incidence of simple atrophy, post-atrophic hyperplasia, and sclerotic atrophy in sextant biopsies was 91%, 47%, and 9%, respectively. Extensive atrophy was observed in 5% of biopsies. Only 2 men (4.7%) in the reviewed group had a subsequent diagnosis of prostate cancer in the 8 years of follow-up. Additionally, prostatic intraepithelial neoplasia was diagnosed in 3 men (7.0%) in the second screening round.

CONCLUSIONS

Atrophy, especially its simple form, is a very common lesion in prostate biopsy cores (94%). Atrophy in an asymptomatic population undergoing screening was not associated with a greater prostate cancer or prostatic intraepithelial neoplasia incidence during subsequent screening rounds.

Additional use of [-2] precursor prostate-specific antigen and "benign" PSA at diagnosis in screen-detected prostate cancer

OBJECTIVES

To evaluate the adjuvant clinical use of [-2] precursor prostate-specific antigen ([-2]pPSA), which is associated with prostate cancer (PCa), and "benign" PSA, related to benign prostatic hyperplasia, in selecting a treatment strategy in patients with screen-detected PCa.

METHODS

Research-use immunoassays (Beckman Coulter) were used to measure [-2]pPSA, sum [-7, -5, -4, and -2]pPSA, and benign PSA from the frozen serum of participants from the screen arm of the European Randomized Study of Screening for Prostate Cancer, section Rotterdam, diagnosed with PCa with a serum PSA level lower than 15 ng/mL. We compared men with relatively benign PCa (Epstein's criteria; group 1) and men with arbitrarily defined aggressive PCa characteristics (Gleason score greater than 4 + 4 and more than four cores with PCa invasion or pT3C disease; group 2).

RESULTS

The data of 61 patients were evaluated. The median age in both groups was 68 years. Total PSA performed best in a univariate analysis, although in the multivariate analysis, the combination of pPSA and percent free PSA could correctly predict 95.5% of group 1 and 82.4% of group 2. The pPSA and percent free PSA forms remained statistically significant in the multivariate analysis of a subgroup of 30 participants normalized for PSA level and prostate volume; combined they correctly identified 89.5% and 54.5% of patients identified as having relatively favorable and aggressive PCa characteristics, respectively.

CONCLUSIONS

Adjuvant clinical use of pPSA over traditional parameters in selecting treatment strategies for men with PCa cannot yet be definitely determined. However, the promising results in a subgroup analysis warrant further investigation.

Innovations in serum and urine markers in prostate cancer current European research in the P-Mark project

An overview is given of serum and urine prostate cancer markers that are currently under investigation and subsequently the P-Mark project is introduced. There are many markers showing promise to overcome the limitations of prostate specific antigen (PSA). Eventually, these markers should be able to increase the specificity in diagnosis, differentiate between harmless and aggressive disease and identify progression towards androgen independence at an early stage. In the P-Mark project, several recently developed, promising markers will be evaluated using clinically well-defined biorepositories. Following successful evaluation, these markers will be validated on a sample set derived from two large, European, prostate cancer studies and used for the identification of special risk groups in the general population. In addition, novel markers will be identified in the same biorepositories by different mass spectrometry techniques.

Features of prostate cancers detected during a prevalence screening round. The Rotterdam experience

INTRODUCTION

Prostate-specific antigen (PSA) testing of asymptomatic men may lead to the detection of "minimal" prostate cancers that are less likely to be associated with morbidity or mortality.

OBJECTIVE

To examine the significance of various diagnostic outcomes from needle biopsies of the prostate in an asymptomatic population of men.

METHODS

Prostatic needle biopsy findings were matched with those from radical prostatectomy specimens using data from the Rotterdam section of the European Randomized study of Screening for Prostate Cancer (ERSPC). Men, aged between 55 and 75 years, with elevated PSA levels underwent lateralized sextant needle biopsies. In corresponding radical prostatectomy specimens, the tumor categories (minimal, moderate, or advanced) were determined.

RESULTS

Prostate cancer was diagnosed in 5.1% of 19,970 screened men, and 31.6 % of the men had cancers that were categorized as "minimal." Repeat biopsies performed after initial diagnoses of either isolated prostatic intra-epithelial neoplasia (PIN) or "suspicious for malignancy," detected adenocarcinoma in 12.1%and 36.5 % of the men, respectively. In a substudy of 510 men with a benign biopsy outcome 12 months previously, repeat biopsies detected adenocarcinoma in 12.4 of the men. Of men who were subsequently treated with radical prostatectomy, the cancers were classified as "minimal" in 27.8% of the men with previously benign biopsies and in 47.4% of the men with previously suspicious lesions,

CONCLUSIONS

The chance of finding a "minimal" prostate cancer in an asymptomatic population is substantial and increases when a repeat biopsy is performed following a biopsy with a suspicious outcome.

[Diagnosis based on prostate needle biopsy: inadequate correlation between pathologic results and clinical course for individual prognosis]

Since the introduction of serum testing for prostate-specific antigen (PSA) in 1990 for the early detection of prostate cancer, the number of men undergoing a prostate needle-biopsy procedure has increased dramatically. In order to highlight the significance of the various diagnostic outcomes of a prostate needle biopsy, the pathological findings from needle biopsies were compared with those from samples taken during radical prostatectomy and in follow-up biopsies, using data from the 'European randomised screening for prostate cancer' (ERSPC) trial. In men with an elevated PSA value and a benign or negative needle-biopsy result, 10-15% were found to have prostate cancer in follow-up biopsies. In men with a needle-biopsy diagnosis of adenocarcinoma, 29% were found to have questionable histopathological characteristics or minimal cancer that did not require therapy. The incidence of minimal cancer increased to 70% among men with a needle-biopsy diagnosis of focal carcinoma, i.e. a small focus (< 3 mm diameter) of well-differentiated adenocarcinoma, based on one biopsy from a series of six. In men with a needle-biopsy diagnosis of 'suspected malignancy' 36.5% were found to have prostate cancer in follow-up biopsies. In men with a needle-biopsy diagnosis of 'high grade prostatic intra-epithelial neoplasia' 13% were found to have prostate cancer in follow-up biopsies. This percentage was not significantly higher than the percentage of cancers detected after an initially benign biopsy outcome. To avoid over-treatment of a substantial number of men who lack symptoms of prostate cancer but are diagnosed on the basis of biopsy results, it is vital that clinical/pathologic parameters are developed and validated that can help in deciding whether to initiate curative treatment immediately.

Screening for prostate cancer

Epidemiologically, prostate cancer is the most common cancer in the Western world after skin cancer. To date, it is still unknown whether screening for prostate cancer is justified, because results of randomised clinical trials are not yet available. The available screening tests (i.e. prostate-specific antigen (PSA) test) do not always detect cancers that otherwise would have resulted in prostate cancer mortality. Favourable results from prostate cancer screening include an increasing number of men with localised disease and an increase in the number of well-differentiated tumours. However, the risk of overdiagnosis and subsequent over-treatment (due to the diagnosis of localised disease), using aggressive therapies fuels arguments against screening. Therefore, until more evidence is available proving otherwise, prostate cancer screening can only be justified in the context of clinical trials.

Low all-cause mortality in the volunteer-based Rotterdam section of the European randomised study of screening for prostate cancer: self-selection bias?

OBJECTIVES

The likelihood of self-selection bias in a cohort of men that entered the volunteer-based randomised prostate cancer screening trial was assessed. In addition, the accuracy of the randomisation was evaluated by comparison amongst the trial arms.

SETTING

The Rotterdam section of the European Randomised Study of Screening for Prostate Cancer (ERSPC). Participants were recruited from population registries and randomised after receipt of written informed consent (49% participation rate).

METHODS

Data from 37,614 men who entered the Rotterdam trial between June 1994 and July 1999 were linked to the Causes of Death Registry of Statistics Netherlands. For the assessment of self-selection bias, mortality in the trial cohort and the area of Rotterdam was compared by calculating standardised mortality ratios (SMRs, 95% confidence interval [CI]). Comparisons between the screening and the control arm were made by means of relative risk (RR).

RESULTS

There were a total of 1661 deaths (4.4%) in the trial cohort, during an average follow-up time of 2.8 years. The observed number of deaths in the two arms combined was lower than expected (SMR 86.7%, 95% CI 81.6-92.1), which was reflected in the major cause of death categories, especially in all malignant neoplasms. No difference was observed in the all-cause mortality rate among the screening and control arm, aged 55-69 years at entry (RR 1.00, 95% CI 0.89-1.12), nor when all causes, excluding prostate cancer mortality, were considered.

CONCLUSIONS

The preliminary results show that the screening and the control arm were comparable, but men recruited for the trial seemed healthier than men in the target population.

PROSTATE CANCER CHARACTERISTICS AND PROSTATE SPECIFIC ANTIGEN CHANGES IN SCREENING DETECTED PATIENTS INITIALLY TREATED WITH A WATCHFUL WAITING POLICY

PURPOSE

We evaluated prostate cancer (PCa) characteristics at diagnosis and changes in prostatic specific antigen (PSA) with time in males with screening detected PCa that was initially managed with a watchful waiting policy.

MATERIALS AND METHODS

Patients with histologically proven PCa and PSA less than 10 ng/ml were selected from the European Randomized Study of Screening for Prostate Cancer, section Rotterdam. The choice of initiating a watchful waiting policy was patient desire or physician advice. PSA slope and PSA doubling time (PSADT) were calculated in patients with 3 or more PSA tests results available.

RESULTS

A total of 191 patients were included. Mean age at diagnosis was 69 years and mean PSA was 3.9 ng/ml. Of the patients 92.6% had a Gleason score of 3 + 3 or lower, 133 had a followup of greater than 12 months (mean 40) and 35 (29.2%) had a negative PSA slope. Mean PSADT was 9.7 years (range 0.3 to 155) in 85 males with a positive PSA slope. During followup 30 patients changed therapy.

CONCLUSIONS

Watchful waiting remains a controversial prostate cancer treatment strategy. In select screening detected patients with PCa there appears to be a subgroup with stable or even decreasing PSA values with time. These males could profit from a watchful waiting policy with possible deferred treatment. Together with conventional tumor parameters at diagnosis PSADT and PSA slope during followup could be used to monitor tumor activity and possibly aid in determining the time of deferred treatment. Further followup is mandatory to validate these results.

Circulating free insulin-like growth factor (IGF)-I, total IGF-I, and IGF binding protein-3 levels do not predict the future risk to develop prostate cancer: results of a case-control study involving 201 patients within a population-based screening with a 4-year interval

Recent studies have reported that serum IGF-I levels in the highest quartile of the normal range and IGF binding protein-3 (IGFBP-3) in the lowest quartile of the normal range are associated with an increased risk of future prostate cancer and/or presence of prostate cancer. It has also been suggested that the measurement of circulating total IGF-I concentrations might be a useful tool for the early detection of prostate cancer in men with moderately increased prostate-specific antigen (PSA) levels. To determine whether circulating free IGF-I, total IGF-I, and IGFBP-3 levels can predict future prostate cancer risk, we prospectively studied prostate cancer characteristics in a cohort of men during two rounds (mean interval, 4 yr) of a population-based screening study for prostate cancer. Two hundred one prostate cancer cases were detected at the second-round screening (aged 55-70 yr), and all these subjects were enrolled in the case group for the present study. Prostate cancer had been confirmed by biopsy in all cases. These 201 subjects were matched with the 201 nonprostate cancer cases by age, serum PSA range at the first-round screening (PSA < 2 ng/ml, n = 67; PSA = 2-3 ng/ml, n = 67; and PSA = 3-4 ng/ml, n = 67), and residence area. At baseline, total IGF-I, free IGF-I, and IGFBP-3 levels and prostate volume of cases with prostate cancer were not different from those of healthy controls. PSA velocity was significantly different between cases and controls (P < 0.001).Stepwise forward logistic regression analysis showed that only PSA levels at baseline and PSA at round 2 after 4 yr are good predictors of prostate cancer, whereas total IGF-I, free IGF-I, and IGFBP-3 did not predict the development of prostate cancer. Only one of the 201 subjects with prostate cancer had metastases. Within the subjects with prostate cancer, there were no differences of IGF-I parameters with different tumor node metastasis categories and/or Gleason scores. Our study suggests that the measurement of serum IGF-I and/or IGFBP-3 concentrations in addition to PSA does not improve the identification of men at high risk to develop early stages of prostate cancer. In addition, our results indicate that the endocrine IGF-I system is not directly involved in the growth of the early stages of prostate cancer.

Prostate-specific antigen velocity at low prostate-specific antigen levels as screening tool for prostate cancer: results of second screening round of ERSPC (ROTTERDAM)

OBJECTIVES

To study retrospectively whether the prostate-specific antigen (PSA) velocity, that is, the change in PSA level over time, might serve as a screening tool in this PSA range. It is estimated that 40% of detectable prostate cancers are present in men with a PSA level of 4.0 ng/mL or less. Digital rectal examination and/or transrectal ultrasonography have been used as screening tools at these low PSA levels, but this approach is not very efficient.

METHODS

The possible predictors (including PSA velocity) for biopsy outcome were studied using univariate and multivariate logistic regression analysis in 774 men who underwent biopsy between November 1997 and January 2002 in the second screening round of the European Randomised Study of Screening for Prostate Cancer (ERSPC). The clinical stage of the tumors was determined, and the Gleason scores of the biopsies were studied.

RESULTS

A total of 149 cancers were found (positive predictive value 19.2%). The odds ratio for the PSA velocity determined by univariate logistic regression analysis was 2.2 (95% confidence interval 0.7 to 6.9, P = 0.19) and was 0.73 (95% confidence interval 0.20 to 2.6, P = 0.64) by multivariate analysis. The distribution of the clinical stage of the detected tumors was 64.4% T1c, 32.2% T2, and 3.4% T3. The biopsy Gleason score was 6 in 84.5%, 7 in 14.2%, and 8 in 1.3%.

CONCLUSIONS

The number of cancers detected in this study and the distribution of clinical stage and biopsy Gleason score confirmed that a relatively large proportion of potentially curable cancers can be found in the low PSA ranges. The PSA velocity did not appear to be a useful screening tool for the identification of these cancers.

Features and preliminary results of the Dutch centre of the ERSPC (Rotterdam, the Netherlands)

OBJECTIVE

To describe the preliminary results of the Dutch section of a large multicentre study of screening for prostate cancer, the European Randomized study of Screening for Prostate Cancer (ERSPC), initiated in the Netherlands and Belgium in 1991.

MATERIALS AND METHODS

After a series of five pilot studies which started in 1991, full-capacity screening started in 1994 with the use of a serum prostate-specific antigen (PSA) determination, a digital rectal examination (DRE) and transrectal ultrasonography (TRUS) as screening tests. Depending on the results and the screening protocol used, men were referred for further examination by sextant biopsies (extended with a seventh biopsy if TRUS showed abnormality). The protocols used, efficiency of the different screening tests, number of cancers detected in the pilot studies, initial screening round and preliminary results of the second screening round are described.

RESULTS

After the pilot studies it became clear that a study of prostate cancer screening was feasible in the Rotterdam area. The screening protocol was workable and the recruitment rate acceptable (39.5%). An inventory of the population registries of Rotterdam and surrounding municipalities, and the known recruitment rate, made it clear that a contribution of 40000 men (aged 55-74 years) from the Dutch centre to the ERSPC was feasible. The initial screening round started in December 1993 and lasted until December 1999 (protocol 5-10). In all, 42376 men were randomized and 1014 cancers detected (5.1%). During this screening the protocol was simplified. After evaluating the different screening tests abnormal results of the DRE and TRUS were omitted as an indication for a sextant biopsy. Only a serum PSA level of > or = 3.0 ng/mL is now used as the indication. The second screening round started in December 1997 and continues. To December 2002, 9920 men were screened for the second time, 4 years after their initial screening visit. To date 446 cancers have been detected (4.5%); this round will last to December 2003. Further evaluation of the screening regimen and characteristics of the cancers detected are constantly assessed within the Dutch ERSPC. Meanwhile a third screening round has also been initiated, which will last to December 2007.

CONCLUSIONS

A prostate cancer screening study of the projected magnitude is feasible in Rotterdam; the recruitment rate is acceptable and the screening tests well tolerated. The study has generated many scientific publications and will be of great value in determining whether prostate cancer screening should be part of general healthcare.

No reason for immediate repeat sextant biopsy after negative initial sextant biopsy in men with PSA level of 4.0 ng/mL or greater (ERSPC, Rotterdam)

OBJECTIVES

In the early detection of prostate cancer (CaP) uncertainty exists concerning the most appropriate biopsy procedure. Within the European Randomized Study of Screening for Prostate Cancer (ERSPC) lateralized sextant biopsies are used. False-negative results of sextant biopsies have led to the extensive use of procedures using 12 or more biopsy cores. The ERSPC offers the opportunity to study the yield of repeat biopsies after 4 years in men who had negative sextant biopsies and a prostate-specific antigen (PSA) level of 4.0 mg/mL or more at the first screening round.

METHODS

Between August 1996 and May 1998, a total of 6876 men (age 55 to 74 years) were randomized to the screening arm and actually underwent screening. The numbers and levels of biopsy indicators, as well as possible predictors for biopsy outcome, in the second screening round, such as prostate volume, volume change over time, prostate-specific antigen density (PSAD), PSA velocity, and age, were calculated and compared for participants with positive and negative biopsies in round 2. The positive predictive value (PPV) and detection rates, as well as parameters of aggressiveness, were evaluated for second-round biopsy-detected and interval CaP cases.

RESULTS

Of the 728 men with a PSA level of 4.0 mg/mL or more who underwent biopsy at initial screening, 553 were eligible for a second screening visit after 4 years. Of these, 272 (49.2%) actually underwent screening. Eighteen CaP cases were detected with 217 biopsies, indicated by a PSA level of 3.0 ng/mL or more (PPV 8.3%). Eight interval cases were identified by linking to the Cancer Registry. These 26 cases would have increased the PPV and detection rate of the initial screening round from 36.1% to 39.7% and from 3.8% to 4.2%, respectively. Most of these cases (23 of 26 or 88.5%) were organ confined and amenable to potentially curative treatment.

CONCLUSIONS

Although the results of this study may have been biased by the low rate of availability/eligibility of participants for rescreening (after 4 years), the proportion of cancers detected after a previous lateral sextant biopsy indicated by a PSA value of 4.0 mg/mL or more (PPV 8.3%) fell far short of the overall PPV at rescreening (PPV 20%). The features of most cancers that were possibly missed during the first round allowed a potentially curative approach. The ERSPC study group found no reason to change the ERSPC protocol.

The value of (−7, −5)pro-prostate-specific antigen and human kallikrein-2 as serum markers for grading prostate cancer

OBJECTIVE

To assess the value of the precursor form (-7,5pro) of prostate-specific antigen (PSA) and human kallikrein-2 (hK2) for detecting and grading prostate cancer, as better serum markers with improved specificity are needed in men with lower ranges of total (t)PSA.

PATIENTS AND METHODS

tPSA, free PSA (fPSA), the precursor (-7,5)proPSA and hK2 were measured in a subset of participants of the European Randomised Study of Screening of Prostate Cancer. In a pilot study, sera from 143 men biopsied but with no prostate cancer, 142 with BPH, and 146 with prostate cancer were analysed to determine the relative value of serum markers for differentiating between the groups. Then, in 141 men with prostate cancer who had a radical prostatectomy, these serum markers were related to the pathological grading to analyse their value as prognostic variables.

RESULTS

Levels of (-7,5)proPSA, hK2 and fPSA could be used to distinguish between BPH and cancer, but proPSA and hK2, alone or combined, did not improve the specificity of fPSA for discriminating BPH and cancer. There was also no correlation between these serum markers and pathological tumour grade.

CONCLUSION

The clinical effect of using (-7,5)proPSA or hK2 for detecting and grading prostate cancer remains limited.

The clinical significance of a small focus of well-differentiated carcinoma at prostate biopsy

OBJECTIVE

To compare a series of 121 sextant needle biopsy sets with their corresponding radical prostatectomy specimens in screened participants in the European Randomized study of Screening for Prostate Cancer (ERSPC), investigating the effect of screening for prostate cancer on disease-specific mortality and quality of life, as the clinical significance of a small focus of well-differentiated prostate cancer on biopsy is unclear.

PATIENTS AND METHODS

The expected clinical significance of the discovered tumours was estimated using an arbitrary model combining volume, grade, and stage characteristics.

RESULTS

Of 34 patients who had a small focus (< 3 mm on a single biopsy core) of well-differentiated carcinoma on biopsy, only 18 (53%) were found to have minimal carcinoma (a small focus of well-differentiated carcinoma) at radical prostatectomy, while 16 (47%) had moderately advanced or advanced carcinoma at radical prostatectomy. The preoperative prediction of minimal carcinoma improved when the amount of cancer in the sextant biopsy set was combined with the preoperative serum prostate specific antigen (PSA) level. Of 12 patients with a small focus of well-differentiated carcinoma on biopsy and a serum PSA of < 4 ng/mL, 11 had minimal carcinoma at radical prostatectomy, while there was minimal carcinoma in only seven of 22 (32%) patients with a small focus of well-differentiated carcinoma on biopsy and a serum PSA of > or = 4 ng/mL.

CONCLUSIONS

The predictive value of a small focus of well-differentiated cancer on systematic sextant biopsy for a small well-differentiated tumour in the prostate is limited. The predictive value improves when serum PSA levels are considered concurrently, but is still considered insufficient to support a base for selecting therapy for the individual patient.

The plication procedure for penile curvature: surgical outcome and postoperative sexual functioning

OBJECTIVE

This study evaluates the patients' judgement of the surgical outcome of the plication procedure, as described by Schröder and Essed, and the postoperative sexual functioning of patients with congenital curvatures and Peyronie's disease.

PATIENTS AND METHODS

Of 98 patients treated for penile curvatures between 1985 and 1996, 85 patients received postoperatively a 'Questionnaire Assessing the Outcome of Surgery' and a short version of the 'Questionnaire for Screening Sexual Dysfunctions'.

RESULTS

28 patients with congenital curvatures and 31 with Peyronie's disease were evaluated. 75% of the patients with congenital curvatures and 58% of the patients with Peyronie's disease were satisfied with the result. Patients treated for Peyronie's disease reported diminished penile length and inability to have sexual intercourse more often than patients with congenital curvatures (90 vs. 64%, and 29 vs. 0%). After correction for age, patients with Peyronie's disease were less satisfied with their present sex life, had more frequent erectile problems and more trouble with considerable sexual desire than a group of 42 controls. For patients with Peyronie's disease satisfaction with the result was positively correlated with satisfaction with their present sex life and negatively correlated with the frequency of erectile problems. For patients with congenital curvatures satisfaction with the result was negatively correlated with both a postoperative curvature and a repeat operation.

CONCLUSIONS

Some patients with Peyronie's disease may not benefit from surgical correction (alone). Because of the occurrence of sexual problems, future evaluation of the role of pre- and postoperative sexological counselling in achieving better results is recommended.

Different PSA assays lead to detection of prostate cancers with identical histological features

OBJECTIVE

Because different PSA assays still show a wide inter-assay variation, we wondered what influence these discrepancies could have on the individual tumour characteristics of the cancers that each of these assays detect in a critical low PSA range. We analysed five different PSA assays in a biopsy simulation with PSA cut-offs of 3.0 and 4.0 ng/ml.

MATERIALS AND METHODS

Randomly taken samples of 360 men with prostate cancer and 96 with benign prostatic disease from a screened population with PSA range of 1.0-6.0 ng/ml (Tandem-E) were investigated. In all cases the diagnosis was confirmed by sextant biopsies. One hundred and thirty-seven men (38%) underwent radical prostatectomy. Variability amongst assays was illustrated in terms of missed cancers and unnecessary biopsies, and in terms of pathologic features of detected cancers at both PSA cut-offs.

RESULTS

Compared to Tandem-E, all assays, except Access, showed significant differences in PSA measurements. Furthermore, none of the assays discriminated significantly between benign and malignant prostatic disease (p>0.05). Tandem-E and Elecsys lead significantly more frequently to the detection of cancers at the cost of more unnecessary biopsies compared to the other assays. Yet, at both PSA cut-offs the proportion of cancers with a certain pathologic grade or stage that were detected by each assay were approximately the same.

CONCLUSIONS

Our study shows that the use of different PSA assays only have consequences for the number, and not for the tumour characteristics of the prostate cancers that are detected. Thus, different PSA assays detect prostate cancers with the same tumour features.

Value of tissue markers p27(kip1), MIB-1, and CD44s for the pre-operative prediction of tumour features in screen-detected prostate cancer

The pre-operative prediction of prognostic tumour features in the radical prostatectomy specimen using routine clinicopathological variables remains limited. The present study evaluated the predictive value of the cell-cycle protein p27(kip1), the proliferation marker MIB-1, and the cell-adhesion protein CD44s, determined on the diagnostic needle biopsy of asymptomatic men screened for prostate cancer. Of 81 screen-detected prostate cancers, representative biopsy cores and matched radical prostatectomy specimens were immunohistochemically stained for these tissue markers. Conventional pre-operative and post-operative clinicopathological variables were assessed and cancers were divided according to a validated tumour classification model (potentially harmless, clinically significant). Low (<50%) p27(kip1) expression, high (> or = 10%) MIB-1 expression, and low (<25%) CD44s expression were considered adverse prognostic signs. Binary logistic regression analysis was performed to assess the most valuable predictors of clinically significant disease. An adverse prognostic immunostaining assessment on the biopsy was found in 10 (12.3%), 17 (21.0%), and 25 (30.9%) cases for p27(kip1), MIB-1, and CD44s, respectively. The concordance in tissue marker assessment between the biopsy specimen and matched radical prostatectomy specimens was low for all three. The positive predictive value (PPV) of p27(kip1) was 90.0%, remarkably higher than that of MIB-1 and CD44s (41.2% and 52.0%, respectively), indicating that a low radical prostatectomy p27(kip1) score is expected if the biopsy p27(kip1) score is low. Logistic regression analysis revealed that biopsy Gleason score (p<0.01) and p27(kip1) assessment (p<0.01) remained the only significant predictors of clinically significant disease. All cases with low p27(kip1) expression were found to have clinically significant disease after radical prostatectomy. The assessment of p27(kip1) in the biopsy specimen might thus assist in distinguishing between potentially aggressive and potentially non-aggressive disease in prostate cancer screening.

Serendipity in detecting disease in low prostate-specific antigen ranges

OBJECTIVE

To assess the magnitude of prostate cancer detection by serendipity (the coincidental detection of prostate cancer during the evaluation of an abnormal screening test result) when a digital rectal examination (DRE) and transrectal ultrasonography (TRUS) are used as initial screening tests for prostate cancer in men with low levels of prostate-specific antigen (PSA; 0.0-3.9 ng/mL).

PATIENTS AND METHODS

In all, 117 participants of a population-based screening study were diagnosed with prostate cancer after a standard evaluation of an abnormal screening test result; 49 underwent radical prostatectomy. Serendipity was defined as either: (i) the presence of prostate cancer opposite to the side that raised suspicion for cancer on DRE and/or TRUS; (ii) a negative lesion-directed biopsy while cancer was present in one or more of the cores of the sextant biopsy; (iii) a tumour volume of < 0.5 mL on radical prostatectomy.

RESULTS

Depending on the definition, 27-63% of prostate cancers detected at low PSA values were detected coincidentally and not as a result of a true-positive test result. The proportion of cancers detected by serendipity was inversely correlated with serum PSA level.

CONCLUSION

A relatively high proportion of prostate cancers diagnosed in men with low PSA levels, and in which a biopsy was prompted by a suspicious DRE and/or TRUS, are considered to be detected by chance only. As these cancers are mostly small (< 0.5 mL), with potentially low biological aggressiveness, relying on serendipity seems disadvantageous in prostate-cancer screening. The level of serendipity in prostate cancer detection, the poor performance of the screening test, and high inter-observer variability, casts further doubt on the utility of DRE (and TRUS) as initial screening tests for prostate cancer in population-based screening.

Feasibility of assessment of promoter methylation of the CD44 gene in serum of prostate cancer patients

BACKGROUND AND PURPOSE

CD44 is an important metastasis-suppressor gene in prostate cancer. Downregulation of the CD44 gene is attributed to transcription repression by methylation of CpG islands in the promoter region. The feasibility of CD44 promoter methylation measurement as a diagnostic tool was assessed in the serum of patients with cancer of the prostate (CAP).

MATERIALS AND METHODS

Seven serum samples of patients with CAP were investigated for CD44 promoter methylation by methylation-specific PCR. Three patients had proven metastatic disease, and four were free of metastases. Tissues from a variety of normal epithelia were assessed as well.

RESULTS

Methylation of the CD44 promoter was readily detectable in all serum samples, although no distinction could be made between patients with and those without metastatic disease on the basis of the signal intensity of methylation-specific PCR products. Remarkably, tissue specimens from different normal epithelia, especially those of the colon and rectum, repeatedly showed aberrant methylation of the promoter region of CD44.

CONCLUSIONS

In the serum of CAP patients, assessment of the methylation status of CpG islands in the promoter region of the CD44 gene is feasible using methylation-specific PCR. However, because of physiologic promoter methylation in normal tissues, including the colorectal mucosa, assessment of methylation of tumor-derived DNA in the serum of cancer patients lacks tissue specificity and seems not to be applicable in clinical settings.

Discordant performance of assays for free and total prostate-specific antigen in relation to the early detection of prostate cancer

OBJECTIVE

To assess the value of applying rigid threshold values in interpreting prostate specific antigen (PSA) results, by selecting and comparing five current methods for measuring free and total PSA.

MATERIALS AND METHODS

Samples taken from an ongoing screening study for prostate cancer (total PSA by Tandem-E assay, 17 334 participants; biopsy criterion a PSA of 3.0 microg/L, 4 464 men) from men with a total PSA of 1.0-6.0 microg/L were measured for free and total PSA using the Access, Immulite, Elecsys and Prostatus analysis kits, in two patient groups, i.e. with prostate cancer or no evidence of disease.

RESULTS

Both patient groups had equal means for total PSA but not for free PSA. In all, 360 samples from men with cancer and 96 from men with no evidence of disease were analysed. All methods applied to both groups deviated statistically significantly from the Tandem-E result for total PSA, except for the Access kit. There was a close correlation among all the methods (correlation coefficients of 0.89-0.97). There were very discordant results for the combination of the Tandem-E vs Prostatus (8% difference), representing 315 participants at a threshold of 3.0 microg/L. For free PSA (free/total PSA) the situation was worse, with extreme differences of 32% and 36% for both patient groups (Elecsys vs Access).

CONCLUSIONS

Depending on the threshold value applied as an indication for biopsy, when using the total PSA alone or combined with the free/total PSA, care is needed in interpreting patient groups because of the discordance among PSA assays.

Peptidylglycine alpha-amidating monooxygenase- and proadrenomedullin-derived peptide-associated neuroendocrine differentiation are induced by androgen deprivation in the neoplastic prostate

Most PCs show NE differentiation. Several studies have tried to correlate NE expression with disease status, but the reported findings have been contradictory. Prostatic NE cells synthesize peptides with a wide spectrum of potential functions. Some of these active peptides, such as PAMP, are amidated. PAM is the only carboxy-terminal peptide-amidating enzyme identified. We studied expression of PAMP and PAM in normal prostate and prostatic tumors (clinical specimens and human xenograft models) with or without prior androgen-deprivation therapy and found a wide distribution of both molecules in NE subpopulations of all kinds. Although the correlation of either marker to tumor grade, clinical progression or disease prognosis did not reach statistical significance, PAMP- or PAM-immunoreactive cells were induced after androgen-blockade therapy. In the PC-310 and PC-295 androgen-dependent models, PAMP or PAM NE differentiation was induced after castration in different ways, being higher in PC-310, which might explain its long-term survival after androgen deprivation. We show induction of expression of 2 new NE markers in clinical specimens and xenografted PC after endocrine therapy.

Prostate cancer: natural history and surgical treatment of localised disease

In summary, there is increasing and convincing evidence that radical prostatectomy is effective in locally confined, poorly differentiated prostate cancer. Diagnostic efforts, therefore, should be targeted toward this disease and probably also, based on the natural history evidence, toward moderately differentiated disease, mainly Gleason score 7. It is unclear, at present, how this can be achieved. Further improvement of our diagnostic capabilities is urgently needed. Hopefully ongoing randomised studies comparing radical prostatectomy to surveillance and studies comparing radical prostatectomy to radiotherapy are urgently desired. The randomised screening studies, which are ongoing, will provide important information with respect to the effect of treatment. If prostate cancer mortality in those men who are randomised to screening turns out to be better than in those randomised to control, this will also be an indication of the effectiveness of treatment. Also, the screening studies and associated natural history studies based on serum repositories and follow-up in non-screened patients will provide important information with respect to the natural history of prostate cancer in relation to PSA and changes of PSA over time. Finally, quality of life with and without treatment will have to be evaluated, in a prospective manner, in multicentre settings according to validated criteria such as those presented by Litwin. The outcomes of such studies will have to be added as utilities to data relating to traditional endpoints such as cancer-specific and overall survival. In the meantime, clinical practice will be determined by the fact that the only way to cure prostate cancer is early diagnosis and aggressive management. Encouragement comes from the increasing volume of evidence showing that poorly differentiated disease can be eradicated as long as it is locally confined.

Inhibition of apoptotic proteins causes multidrug resistance in renal carcinoma cells

Renal Cell Carcinomas (RCCs) exhibit strong resistance to the most chemotherapeutic treatments probably due to the expression of various multidrug resistance (MDR) genes. Overexpression of P-glycoprotein (Pgp) is established as one such factor, but other mechanisms such as at-MDR, characterized by attenuated DNA-topoisomerase II (topoII) activity, may be functional as well. In addition, regulating proteins involved in apoptosis can exhibit multidrug resistant features. However, prevention of apoptosis as a mechanism of MDR has not yet been assessed in RCC, nor has the cytotoxicity of a variety of chemotherapeutic agents known to trigger apoptotic or necrotic cell death been tested in RCC in a systematic fashion. Using immunohistochemistry and Western blotting, Bcl-2 and Bax expression was determined in a panel of multidrug resistant RCC lines featuring Pgp and/or at-MDR. The results were related to apoptotic activity and kind of cell death in these cell lines, demonstrated by incubation with Hoechst 33342 and propidium iodide after treatment with various cytotoxic agents and quantitated by MTT. In the drug resistant sublines, some decreased Bax and strongly increased Bcl-2 expression was seen by immunohistochemistry indicating prevention of apoptosis as a distinct feature of MDR in RCC. This was confirmed by Western blotting. Sublines revealed significant resistance for all drugs, except for CC-313 and DiMIQ. However, these drugs induced necrotic cell death, in contrast to all other drugs tested, which induced apoptotic cell death. We conclude that, in chemoselected RCC sublines, multidrug resistance appears to be functional due to inhibition of apoptosis, apart from the MDR1 and at-MDR resistance mechanisms. CC-313 and DiMIQ are very potent cytotoxic agents in RCC, probably because they do not kill by induction of apoptosis.

The predictive value for prostate cancer of lesions that raise suspicion of concomitant carcinoma: an evaluation from a randomized, population-based study of screening for prostate cancer

BACKGROUND

Suspicion of prostate carcinoma may persist after an initial negative biopsy result, and repeated biopsy is suggested. The authors assessed whether diagnostic follow-up of men with an initial diagnosis of isolated, high-grade prostatic intraepithelial neoplasia (HPIN) and a prostate biopsy suspicious for malignancy (PBSM) is needed.

METHODS

The frequency of isolated HPIN and PBSM was determined in 4057 participants of a population-based screening study who underwent systematic sextant transrectal biopsy. The predictive value for prostate carcinoma of HPIN and PBSM was determined by performing repeated biopsies at 6-week interval. The additional predictive value for malignant disease within a screened population was assessed by performing repeated biopsies at a 1-year interval in 462 consecutively recruited men with an initial benign biopsy result. Participants were subjected to a second screening at a 4-year interval. The biopsy and radical prostatectomy tumor features were determined.

RESULTS

Isolated HPIN and PBSM were diagnosed in 0.8% and 2.6% of biopsied men, respectively. The detection rates on repeated biopsy were 10.0% (3 of 30 men) for isolated HPIN, 38.7% (36 of 93 men) for PBSM, and 11.0% (51 of 462 men) for those with initial benign biopsy results. Except for two men (one with PBSM and one with HPIN), all others remained free of prostate carcinoma at their second screening. Features of the tumors that were detected after PBSM were comparable to those that were detected on initial biopsy, whereas the few tumors that were diagnosed after HPIN had highly favorable features.

CONCLUSIONS

Compared with men who have PBSM, men with isolated HPIN on initial biopsy are at no greater risk of being diagnosed with prostate carcinoma than if their initial biopsies were assessed as benign only. Moreover, the features of tumors that are diagnosed after an evaluation of HPIN warrant no early, extensive diagnostic follow-up.

Pathologic features of prostate cancer found at population-based screening with a four-year interval

BACKGROUND

The currently recommended frequency for prostate-specific antigen (PSA) screening tests for prostate cancer is 1 year, but the optimal screening interval is not known. Our goal was to determine if a longer interval would compromise the detection of curable prostate cancer.

METHODS

A cohort of 4491 men aged 55-75 years, all participants in the Rotterdam section of the European Randomized Study of (population-based) Screening for Prostate Cancer, were invited to participate in an initial PSA screening. Men who received that screening were invited for a second screen 4 years later. Pathology findings from needle biopsy cores were compared for men in both rounds. Statistical tests were two-sided.

RESULTS

A total of 4133 men were screened in the first round (the prevalence screen), and 2385 were screened in the second round. The median amount of cancer in needle biopsy sets was 7.0 mm (95% confidence interval [CI] = 5.4 mm to 8.6 mm) in the first round and 4.1 mm (95% CI = 2.6 mm to 5.6 mm) in the second round (P =.001). Thirty-six percent of the adenocarcinomas detected in the first round but only 16% of those detected in the second round had a Gleason score of 7 or higher (mean difference = 20% [95% CI = 10% to 30%]; P<.001). Whereas 25% of the adenocarcinomas detected in the first round had adverse prognostic features, only 6% of those detected in the second round did (mean difference = 19% [95% CI = 11% to 26%]; P<.001). Baseline PSA values were predictive for the amount of tumor in biopsies in men with cancer in the first round but not for that in the second round.

CONCLUSION

Most large prostate cancers with high serum PSA levels were effectively detected in a prevalence screen. In this population, a screening interval of 4 years appears to be short enough to constrain the development of large tumors, although it is inconclusive whether this will result in a survival benefit.

Cytokine production induced by binding and processing of calcium oxalate crystals in cultured macrophages

Deposition of calcium oxalate (CaOx) crystals in the renal interstitium is common in humans with primary oxalosis and secondary hyperoxaluria, as well as in kidneys of rats with CaOx nephrolithiasis. In vivo, macrophages and multinucleated giant cells mostly encapsulate these crystals. To investigate whether macrophages are able to dispose of CaOx crystals after phagocytosis, we used a nontransformed macrophage cell line derived from mouse spleen progenitors. Cytokine assays showed that in response to crystal binding and phagocytosis, these macrophages release tumor necrosis factor-alpha. This release was evident at 8 hours, maximal at 24 hours, and decreased to control values after 48 hours of incubation with crystals. A very low but significant release of interleukin-6 into the culture medium was only noticed after 32 hours. Radiochemical experiments showed that these cells bind 38.8% of the CaOx crystals added. After 4 days, all internalized crystals had been dissolved and their molecular constituents released into the extracellular environment. Confocal laser scanning microscopy followed by morphometrical analyses confirmed these results. Long-term (survival) analyses showed that in the interval under study and at the crystal doses used, cell viability was not significantly affected. These findings support the view that properly functioning macrophages are able to remove CaOx deposits from the renal interstitium and that these cells produce inflammatory cytokines before crystal dissolution.

Sexual functioning in patients with localized prostate cancer awaiting treatment

This article evaluates current sexual functioning in patients with prostate cancer who are awaiting treatment. One-hundred fifty-eight patients filled out a 15-item questionnaire regarding current sexual functioning. Median age was 67 years. Sixty percent reported to have spontaneous erections at least once a week, and 37% reported a good firmness. Thirty-five percent reported that during sexual activity they had no difficulty in getting erections, and 33% reported that they had no difficulty in maintaining an erection. After diagnosis, all patients reported a decrease in sexual interest, activity, and pleasure. Diagnosis of prostate cancer does have an impact on sexual functioning, therefore sexual counseling prior to treatment is advised.

Why phase III trials of maximal androgen blockade versus castration in M1 prostate cancer rarely show statistically significant differences

BACKGROUND

The meta-analysis of maximal androgen blockade (MAB) concluded that there is no survival advantage of MAB over castration alone. However, the results from the largest trials yield conflicting results.

METHODS

The design and results of three trials were examined.

RESULTS

Most studies were planned to detect an over-optimistic difference in survival and immature data were published. The survival curves show that statistical assumptions are not fulfilled. Excluding from the meta-analysis all trials where a negative impact of disease flare on survival could not be excluded resulted in no difference in survival between MAB and castration.

CONCLUSIONS

Trials of MAB should be planned to detect differences of no more than 5-10% in median survival. The analyses should only be carried out on mature data and should take into account the possibility of a negative impact on survival due to disease flare if no anti-androgen has been given initially with an LH-RH agonist.

Tumor characteristics in screening for prostate cancer with and without rectal examination as an initial screening test at low PSA (0.0-3.9 ng/ml)

BACKGROUND

The value of rectal examination as initial screening test for prostate cancer at low PSA values (0.0-3.9 ng/ml) was determined by evaluating the number and tumor characteristics of the cancers detected.

METHODS

Two study populations were subjected to screening with (n = 10,226) and without (n = 10,753) rectal examination as initial screening test. The number of cancers detected at low PSA values for both screening regimens, the corresponding biopsy and radical prostatectomy tumor characteristics were assessed. Possibly harmless cancers were defined as small (< 0.5 ml) organ-confined tumors without Gleason growth-patterns 4/5.

RESULTS

At low PSA, 26.6% (117/440) of screen-detected cancers were detected after the evaluation of a suspicious rectal examination. The number of cancers and tumor aggressiveness features were highly associated with serum-PSA level. The proportion of possibly harmless disease steadily declined from 100% (PSA 0.0-0.9 ng/ml) to 15.4% (PSA 3.0-3.9 ng/ml). Rectal examinations were performed unnecessarily in 94.7-100% of cases, when detection of clinically significant disease was aimed at. Using PSA (and a cut-off of 3.0 ng/ml) as the only screening tool, 24.3% (121/498) of screen-detected cancers were in the PSA range 3.0-3.9 ng/ml, and 60.0% were assessed as clinically significant.

CONCLUSIONS

Rectal examination as initial screening test for prostate cancer at low PSA values may be replaced by screening using serum-PSA only. At PSA levels below 3.0 ng/ml, 289 rectal examinations are required to find one case of clinically significant disease, and 96 rectal examinations are needed to diagnose prostate cancer of any size, grade, or stage.