How much does Gleason grade of follow-up biopsy differ from that of initial biopsy in untreated, Gleason score 4-7, clinically localized prostate cancer?

[Active surveillance of prostate cancer]

The aim of active surveillance (AS) is to avoid overtreatment of clinically insignificant prostate cancer (PCa). It is now strongly recommended for patients diagnosed with localized low-risk PCa. Additionally, it can be considered for selected patients with localized PCa in the International Society of Urological Pathology (ISUP) group 2, provided patients have a favorable risk profile. This profile is histopathologically characterized by the presence of a low percentage of Gleason pattern 4 and the absence of cribriform or intraductal components. The role of magnetic resonance imaging (MRI), including the Prostate Cancer Radiological Estimation of Change in Sequential Evaluation (PRECISE) recommendations on monitoring is increasing. It is crucial to adhere to defined intervals for prostate-specific antigen (PSA) level checks, repeat biopsies, MRI and further targeted and systematic biopsies under AS. The MRI of the prostate (according to the current recommendations as multiparametric MRI, mpMRI), as a noninvasive diagnostic tool, has the potential to be used as a decision aid for determining the need for repeated biopsies during AS. As the trigger for deciding for an active treatment PSA progression alone is not sufficient but there must be a biopsy-confirmed tumor progression with an upgrading. This continuing medical education (CME) article summarizes the current indications, procedures and discontinuation criteria for AS based on the latest evidence and an adaptation to international guidelines.

Predicting the aggressiveness of peripheral zone prostate cancer using a fractional order calculus diffusion model

PURPOSE

To evaluate the performance of parameters D, β, μ from the Fractional Order Calculus (FROC) model at differentiating peripheral zone (PZ) prostate cancer (PCa) MATERIAL AND METHODS: 75 patients who underwent targeted MRI-guided TRUS prostate biopsy within 6 months of MRI were reviewed retrospectively. Regions of interest (ROI) were placed on suspicious lesions on MRI scans. ROIs were then correlated to pathological results based on core biopsy location. The final tumor count is a total: 23 of GS 6 (3 + 3), 36 of GS 7 (3 + 4), 18 of GS 7 (4 + 3), and 19 of GS ≥ 8. Diffusion-weighted imaging (DWI) scans were fitted into the FROC and monoexponential model to calculate ADC and FROC parameters: anomalous diffusion coefficient D, intravoxel diffusion heterogeneity β, and spatial parameter μ. The performance of FROC parameters and ADC at differentiating PCa grade was evaluated with receiver operating characteristic (ROC) analysis.

RESULTS

In differentiating low (GS 6) vs. intermediate (GS 7) risk PZ PCa, combination of (D, β) provides the best performance with AUC of 0.829 with significance of p = 0.018 when compared to ADC (AUC of 0.655). In differentiating clinically significant (GS 6) vs. clinically significant (GS ≥ 7) PCa, combination of (D, β, μ) provides highest AUC of 0.802 when compared to ADC (AUC of 0.671) with significance of p = 0.038. Stratification of intermediate (GS 7) and high (GS ≥ 8) risk PCa with FROC did not reach a significant difference when compared to ADC.

CONCLUSION

Combination of FROC parameters shows greater performance than ADC at differentiating low vs. intermediate risk and clinically insignificant vs. significant prostate cancers in peripheral zone lesions. The FROC diffusion model holds promise as a quantitative imaging technique for non-invasive evaluation of PZ PCa.

[Active surveillance in prostate cancer]

Prostate cancer remains among the most commonly diagnosed malignancies worldwide in men. In patients with low-risk prostate cancer, the risk of metastasis and mortality is very low; therefore, a tumor surveillance strategy can be used. In patients undergoing active surveillance, curative active therapy is postponed without compromising opportunities for cure until there is evidence of progression or the patient desires active therapy. The aim of active surveillance in prostate cancer patients is to minimize treatment-related toxicity without impairing patient survival. To maintain patients under active surveillance, the following criteria should be met: prostate-specific antigen (PSA) ≤10 ng/ml, Gleason score ≤6, cT1 or cT2a, ≤2 biopsy cores with <50% cancer involvement of every positive core. Follow-up in active surveillance patients is based on repeat biopsy, serial PSA measurements, and digital rectal examination.

Baseline and longitudinal plasma caveolin-1 level as a biomarker in active surveillance for early-stage prostate cancer

OBJECTIVES

To evaluate the role of caveolin-1 (Cav-1) as a predictor of disease reclassification (DR) in men with early prostate cancer undergoing active surveillance (AS).

PATIENTS AND METHODS

We analysed archived plasma samples prospectively collected from patients with early prostate cancer in a single-institution AS study. Of 825 patients enrolled, 542 had ≥1 year of follow-up. Baseline and longitudinal plasma Cav-1 levels were measured using an enzyme-linked immunosorbent assay. Tumour volume or Gleason grade increases were criteria for DR. Logistic regression analyses were used to assess associations between clinicopathological characteristics and reclassification risk.

RESULTS

In 542 patients, 480 (88.6%) had stage cT1c disease, 542 (100.0%) had a median prostate-specific antigen level of 4.1 ng/mL, and 531 (98.0%) had a median Cancer of the Prostate Risk Assessment score of 1. In all, 473 (87.3%) had a Gleason score of 3+3. After a median of 3.1 years of follow-up, disease was reclassified in 163 patients (30.1%). The mean baseline Cav-1 level was 2.2 ± 8.5 ng/mL and the median 0.2 ng/mL (range, 0-85.5 ng/mL). In univariate analysis, baseline Cav-1 was a significant predictor for risk of DR (odds ratio [OR] 1.82, 95% confidence interval [CI] 1.24-2.65; P = 0.002). In multivariate analysis, with adjustments for age, tumour length, group risk stratification and number of positive cores, reclassification risk associated with Cav-1 remained significant (OR 1.91, 95% CI 1.28-2.84; P = 0.001).

CONCLUSION

Baseline plasma Cav-1 level was an independent predictor of disease classification. New methods for refining AS and intervention may result.

Gleason Upgrading with Time in a Large Prostate Cancer Active Surveillance Cohort

PURPOSE

We report the percentage of patients on active surveillance who had disease pathologically upgraded and factors that predict for upgrading on surveillance biopsies.

MATERIALS AND METHODS

Patients in our active surveillance database with at least 1 repeat prostate biopsy were included. Histological upgrading was defined as any increase in primary or secondary Gleason grade on repeat biopsy. Multivariate analysis was used to determine baseline and dynamic factors associated with Gleason upgrading. This information was used to develop a nomogram to predict for upgrading or treatment in patients electing for active surveillance.

RESULTS

Of 862 patients in our cohort 592 had 2 or more biopsies. Median followup was 6.4 years. Of the patients 20% were intermediate risk, 0.3% were high risk and all others were low risk. During active surveillance 31.3% of cases were upgraded. On multivariate analysis clinical stage T2, higher prostate specific antigen and higher percentage of cores involved with disease at the time of diagnosis predicted for upgrading. A total of 27 cases (15% of those upgraded) were Gleason 8 or higher at upgrading, and 62% of all 114 upgraded cases went on to have active treatment. The nomogram incorporated clinical stage, age, prostate specific antigen, core positivity and Gleason score. The concordance index was 0.61.

CONCLUSIONS

In this large re-biopsy cohort with medium-term followup, most cases have not been pathologically upgraded to date. A model predicting for upgrading or radical treatment was developed which could be useful in counseling patients considering active surveillance for prostate cancer.

A tale of two trials: The impact of 5α-reductase inhibition on prostate cancer (Review)

The use of 5α-reductase inhibitors (5α-RIs) as prostate cancer chemoprevention agents is controversial. Two large randomized trials, the Prostate Cancer Prevention Trial (PCPT) and the Reduction by Dutasteride of Prostate Cancer Events (REDUCE) Trial, have both shown a decreased incidence of prostate cancer in patients administered with 5α-RIs. Both studies showed, however, an increased risk of higher-grade prostate cancer. Numerous studies have since analyzed the inherent biases in these landmark studies and have used mathematical modeling to estimate the true incidence of prostate cancer and the risk for high-grade prostate cancer in patients undergoing 5α-RI treatment. All primary publications associated with the PCPT and REDUCE studies were reviewed in detail. Pertinent references from the above publications were assessed and a literature search of all published articles associated with PCPT, REDUCE or 5α-RIs as chemopreventative agents through October 2013 was performed using Pubmed/Medline. PCPT and REDUCE both showed a significant decrease in the incidence of prostate cancer following the administration of 5α-reductase inhibitor, as compared with placebo, suggesting that 5α-RIs may be effective agents for prostate cancer chemoprevention. Inherent biases in the design of these two studies may have caused an artificial increase in the number of high-grade cancers reported. Mathematical models, that integrated data from these trials, revealed neither an increased nor decreased risk of high-grade disease when taking these biases into consideration. Moderately strong evidence exists that 5α-RIs may reduce the risk of prostate cancer. PCPT and REDUCE showed a decreased prevalence of prostate cancer in patients taking 5α-RIs. Urologists should have a working knowledge of these studies and discuss with patients the risks and benefits of 5α-RI treatment. Further studies to evaluate the cost-effectiveness of chemoprevention with 5α-RIs and appropriate patient selection are warranted.

Gleason grade progression is uncommon

Gleason grade is universally used for pathologic scoring of the differentiation of prostate cancer. However, it is unknown whether prostate tumors arise well differentiated and then progress to less differentiated forms or if Gleason grade is an early and largely unchanging feature. Prostate-specific antigen (PSA) screening has reduced the proportion of tumors diagnosed at advanced stage, which allows assessment of this question on a population level. If Gleason grade progresses as stage does, one would expect a similar reduction in high-grade tumors. We studied 1,207 Physicians' Health Study and Health Professionals Follow-up Study participants diagnosed with prostate cancer from 1982 to 2004 and treated with prostatectomy. We compared the distribution of grade and clinical stage across the pre-PSA and PSA screening eras. We re-reviewed grade using the ISUP 2005 revised criteria. The proportion of advanced stage tumors dropped more than six-fold, from the earliest period (12/1982-1/1993), 19.9% stage ≥ T3, to the latest (5/2000-12/2004), 3% stage T3, none T4. The proportion of Gleason score ≥ 8 decreased substantially less, from 25.3% to 17.6%. A significant interaction between stage and diagnosis date predicting grade (P = 0.04) suggests that the relationship between grade and stage varies by time period. As the dramatic shift in stage since the introduction of PSA screening was accompanied by a more modest shift in Gleason grade, these findings suggest that grade may be established early in tumor pathogenesis. This has implications for the understanding of tumor progression and prognosis, and may help patients diagnosed with lower grade disease feel more comfortable choosing active surveillance.

TOOKAD(®) Soluble vascular-targeted photodynamic (VTP) therapy: determination of optimal treatment conditions and assessment of effects in patients with localised prostate cancer

OBJECTIVES

To evaluate the optimal treatment conditions and effects of TOOKAD(®) Soluble vascular-targeted photodynamic (VTP) therapy in patients with localised prostate cancer. To evaluate the safety and quality of life after TOOKAD(®) Soluble VTP treatment in patients with localised prostate cancer.

PATIENTS AND METHODS

Men (aged >18 years) diagnosed with localised prostate cancer, who were suitable for active surveillance, were invited to take part in the study. Patients who had received prior or current treatment for their cancer were excluded. There were two parts to the study: in part one, patients were assigned to one of two treatment groups based on the size of their prostates (patients with prostate size <60 mL would receive 4 mg/kg TOOKAD(®) Soluble and patients with prostate size ≥60 mL would receive 6 mg/kg TOOKAD(®) Soluble both activated with 200 J/cm light). In part two, patients were assigned to one of two treatment groups based on predefined criteria and received either 4 or 6 mg/kg TOOKAD(®) Soluble and 200 or 300 J/cm light. VTP was conducted under general anaesthesia using TOOKAD(®) Soluble administered intravenously and activated by light-diffusing fibres within the prostate via the perineum. Follow-up was conducted for 6 months. Magnetic resonance imaging (MRI) carried out at 1 week after VTP and transrectal prostate biopsy at 6 months were the key endpoints. Adverse event (AE) recording and patient-reported outcome measures were collected.

RESULTS

In all, 86 patients were enrolled in the study and 85 patients received treatment. Of the 85 treated patients, one patient discontinued (due to withdrawal of consent). At 6 months, 61/83 (74%) patients who underwent prostate biopsy had histopathology that was negative for prostate cancer (95% confidence interval (CI) 62.7-82.6%). Considering patients who received 4 mg/kg TOOKAD(®) Soluble and 200 J/cm light (unilateral), which are considered optimal treatment parameters, 38/46 (83%) patients had histopathology from the biopsies that was negative for prostate cancer at 6 months (95% CI 68.6-92.2%; P < 0.001). The mean percentage of necrosis of the targeted prostate tissue at 7 days after VTP was 78% overall (83 patients) with extraprostatic necrosis reported in 76% (63/83) of patients. Considering patients who received 4 mg/kg TOOKAD(®) Soluble and 200 J/cm light (unilateral), the mean 7-day necrosis percentage was 88% (46 patients) with extraprostatic necrosis reported in 72% (33/46) of patients. All occurrences of extraprostatic necrosis were considered clinically acceptable and none were associated with any clinical sequelae. The mean percentage prostate necrosis at 7 days was statistically significantly higher (P < 0.001) in patients treated with a therapeutic light density index (LDI) of ≥1 than those treated with a LDI of <1. The percentage of patients with negative biopsies at 6 months was also higher in patients treated with a therapeutic LDI of ≥1 than those treated with a LDI of <1 (78.6% and 63.0%, respectively). In all, 87% (75/86) of patients reported at least one treatment-emergent AE during the study. Most AEs were mild or moderate in intensity and considered related to the technical procedures of the study. No treated patients had hypotension or discontinued due to AEs. Eight patients (9.3%) had serious AEs; none resulted in discontinuation from the study.

CONCLUSIONS

Biopsy data, post-treatment dynamic contrast-enhancement MRI at 1 week after VTP and analysis of the safety data have shown that 4 mg/kg TOOKAD(®) Soluble and 200 J/cm light are the optimal treatment conditions for the VTP procedure resulting in >80% of patients treated with this regimen having a negative biopsy at 6 months. Overall, the treatment was well tolerated and exhibited early signs of efficacy for minimally invasive focal treatment of localised prostate cancer.

Prostate cancer chemoprevention

Prostate cancer is a leading cause of morbidity and mortality in men and has significant treatment-associated complications. Prostate cancer chemoprevention has the potential to decrease the morbidity and mortality associated with this disease. Chemoprevention research to date has primarily focused on nutrients and 5 alpha-reductase inhibitors (5ARIs). A large randomized trial (SELECT) found no favorable effect of selenium or vitamin E on prostate cancer prevention. Two large randomized placebo controlled trials (the PCPT and REDUCE trials) have been published and have supported the role of 5ARIs in prostate cancer chemoprevention; however, these trials also have prompted concerns regarding the increase in high-grade disease seen with treatment and have not been approved by the US Food and Drug Administration (FDA) for chemoprevention. Conclusive evidence for the chemopreventive benefit of nutrients or vitamins is lacking, whereas the future role of 5ARIs remains to be clarified.

Primary androgen deprivation (AD) followed by active surveillance (AS) for newly diagnosed prostate cancer (PC): A retrospective study

BACKGROUND

Active surveillance (AS) is only recommended for Low-Risk prostate cancer (PC) with <34% biopsies positive. Studies describing the long-term outcome of men treated with androgen deprivation (AD) followed by AS are sparse.

MATERIALS AND METHODS

One hundred two men were treated with 12 months of AD in a medical oncology clinic specializing in PC between 1998 and 2007 and were followed for a median of 7.25 years. The biopsy complete response rate after AD and the incidence of disease progression while on subsequent AS was assessed. Baseline age, D'Amico risk category, PSA velocity, percentage core biopsies, and prostate volume were evaluated as potential predictors of disease progression.

RESULTS

D'Amico risk category for the 102 men: Low: n = 22, Intermediate: n = 30, and High: n = 50. Medians: Age 67.3, PSA 7.8, Gleason 3 + 4, >50% core biopsies positive, stage T1c. Seventy men had a clear biopsy and 31 of these had disease progression leading to additional treatment after a median of 52 months. D'Amico risk category of the 57 men with a positive biopsy after AD or disease progression on AS was: Low: n = 4 (18%), Intermediate: n = 16 (53%), and High: n = 37 (74%). No PC deaths occurred. Three men had clinical progression. In stepwise logistic regression analysis only higher D'Amico risk category and lower prostate volume predicted disease progression.

CONCLUSIONS

Despite a high prevalence of ≥50% core biopsies positive at baseline, AD induces durable remissions in most men with Low-Risk and about half with Intermediate-Risk PC.

Prostate cancer specific survival in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial

BACKGROUND

The prostate component of the Prostate, Lung, Colorectal, and Ovarian (PLCO) randomized screening trial demonstrated no mortality effect of screening. Here we analyze prostate cancer specific survival in PLCO and its relation to screening.

METHODS

76,693 men aged 55-74 were randomized to usual care (n = 38,350) or intervention (n = 38,343). Intervention arm men received annual prostate-specific antigen (6 years) and digital rectal exam (4 years). Men were followed for cancer diagnosis and mortality through 13 years. Medical record abstractors confirmed prostate cancer diagnoses, stage and grade. Prostate-specific survival in PLCO cases was analyzed using Kaplan-Meier analysis and proportional hazards modeling. We utilized data from the Surveillance, Epidemiology and End Results (SEER) program to compute expected survival in PLCO and compared this to observed.

RESULTS

There was no significant difference in prostate-specific survival rates between arms; 10 year survival rates were 94.7% (intervention, n = 4250 cases) versus 93.5% (usual care, n = 3815 cases). Within the intervention arm, cases never screened in PLCO had lower 10 year survival rates (82%) than screen detected or interval (following a negative screen) cases, both around 95.5%. The ratio of observed to expected 10 year prostate-specific death (1-survival) rates was 0.59 (95% CI: 0.51-0.68) for all PLCO cases, 0.66 (95% CI: 0.51-0.81) for Gleason 5-7 cases and 1.07 (95% CI: 0.87-1.3) for Gleason 8-10 cases.

CONCLUSION

Prostate cancer specific survival in PLCO was comparable across arms and significantly better than expected based on nationwide population data. How much of the better survival is due to a healthy volunteer effect and to lead-time and overdiagnosis biases is not readily determinable.

Active surveillance for prostate cancer: past, present and future

PURPOSE OF REVIEW

This article reviews recent developments in the use of active surveillance for localized prostate cancer.

RECENT FINDINGS

The treatment of localized prostate cancer continues to be a major challenge for urologic oncologists. Screening with prostate-specific antigen has resulted in increased numbers of low-risk prostate cancers being detected. Aggressive whole-gland therapy with surgery, or radiation therapy is associated with potentially life-altering treatment-related side effects such as urinary incontinence, bowel toxicity and erectile dysfunction. The goal of active surveillance is to avoid or delay the adverse events associated with prostate cancer therapy while still allowing for curative intervention in the future, if needed.

SUMMARY

Active surveillance is a reasonable treatment option for many men with low-risk, and some men with intermediate-risk, prostate cancer. Additional research is needed to determine the optimal active surveillance inclusion criteria, monitoring schedule, and treatment triggers. It is hoped that advances in prostate imaging, biomarkers, and focal therapy will foster greater use of active surveillance in appropriately selected men to optimize quality-of-life without compromising cancer outcomes.

Transrectal ultrasonography-guided biopsy does not reliably identify dominant cancer location in men with low-risk prostate cancer

Study Type - Diagnostic (exploratory cohort) Level of Evidence 2b What's known on the subject? and What does the study add? The widespread use of serum PSA testing followed by TRUS-guided biopsy have resulted in profound prostate cancer stage migration with many patients presenting with focal rather than multifocal disease. There is increasing interest in the use of focal rather than whole-gland treatment. However, current biopsy schemes may still miss cancer or, even when cancer is identified, its extent or grade might not be accurately characterized. In order for focal therapy to be effective, the area of highest tumour volume and/or grade needs to localized accurately. The aim of this study was to assess how well biopsy, as currently performed, locates the focus of highest prostate cancer volume and/or grade.

OBJECTIVE

To evaluate the ability of transrectal ultrasonography (TRUS)-guided extended core biopsy to identify the dominant tumour accurately in men with early stage prostate cancer.

PATIENTS AND METHODS

Patients with early stage, low-risk prostate cancer who subsequently underwent radical prostatectomy (RP) and had complete surgical specimens were identified. Re-review was performed by a single uropathologist using ImageJ software to identify tumour location, dominant grade (DG) and dominant volume (DV). Pathology findings were then compared with biopsy results.

RESULTS

A total of 51 men with early stage, low-risk prostate cancer, who had undergone RP, had complete specimens for review and a median of 15 biopsy cores taken for diagnosis and grading. Sixteen men had a single diagnostic biopsy, 21 had one repeat biopsy, and 14 had two or more repeat biopsies. Compared with surgical findings, biopsy correctly identified the sextant with the largest tumour volume in 55% (95% CI 0.5-0.6) of specimens and the highest grade in 37% (95 CI 0.3-0.5). No demographic or clinical factors were significantly associated with identification of DG. Interval between last biopsy and RP, total tissue length taken and total length of tumour identified were significantly associated with correct identification of DV.

CONCLUSIONS

Our findings show that TRUS-guided biopsy detects and localizes DV better than it does DG. Even with an extended scheme, TRUS-guided biopsy does not reliably identify dominant cancer location in this low-risk cohort of men with early stage prostate cancer. TRUS-guided biopsy may perform better in similar men with low stage, but higher volume disease.

Chemoprevention of prostate cancer

Over the past two decades, many more men are diagnosed with prostate cancer then die of the disease. This increase in diagnosis has led to aggressive treatment of indolent disease in many individuals and has been the impetus for finding a means of reducing the risk of prostate cancer. In the past decade, there have been eight large trials of prostate cancer risk reduction using dietary supplements, 5α-reductase inhibitors, or anti-estrogens. The only two trials which have demonstrated efficacy are those involving 5α-reductase inhibitors: the PCPT (finasteride) and REDUCE (dutasteride). This review examines prostate cancer risk reduction, with emphasis on conclusions that can be drawn from these two landmark studies.

[Active surveillance for localized prostate cancer]

Active surveillance as an alternative approach to immediate curative treatment is demonstrated for an increasing number of patients with low risk prostate cancer. Optimization of selection and surveillance criteria to guarantee a low risk issue to patients are discussed in this review. They lead to consider active surveillance as an option rather than a standard of care for patients ideally included in clinical research protocols.

Words of wisdom. Re: Effect of dutasteride on the risk of prostate cancer. Andriole G, Bostwick D, Brawley O, et al. N Engl J Med 2010;362:1192-202

This is the first published report of the REDUCE (Reduction by Dutasteride of Prostate Cancer Events) trial, a 4-yr, multicenter, randomized, double-blind, placebo-controlled study involving 6729 men and comparing dutasteride 0.5 mg daily to placebo. The study was similar to the Prostate Cancer Prevention Trial (PCPT) [1] with some key differences. To be eligible, men had to have a prostate-specific antigen (PSA) level between 2.5 and 10 ng/ml, and a prior negative prostate biopsy (6-12 cores) within 6 mo before enrollment (vs a PSA <3.0 in PCPT); and the biopsies were at 2 and 4 yr (vs 7 yr). The primary end point was the presence of cancer on 10-core biopsy at 2 and 4 yr. Eighty-three percent of participants were biopsied(vs < 50% in PCPT). Less than 7% of cancers were diagnosed on protocol-independent biopsies (vs 52% of cancers diagnosed on for-cause biopsies in PCPT). Of the 3305 men in the dutasteride group and the 3424 men in the placebo group, 659 (20%) and 858 (25%), respectively, had cancer on the follow-up biopsies-an absolute reduction of 5.1% and a relative risk reduction of 23% ( p < 0.001). There was no difference between the groups in Gleason 7-10 cancers overall. Twenty-nine patients on dutasteride had Gleason 8-10,compared with 19 on placebo ( p = 0.15). The most likely explanation for this difference was the removal of 141 more men from the trial with Gleason 5-7 cancers. Based on surveillance studies, about 7% would be upgraded to Gleason 8-10 on rebiopsy [2]. Dutasteride also decreased the rate of urinary retention (1.6% vs 6.7%: a 77.3% relative reduction).

Prostate cancer managed with active surveillance: role of anatomic MR imaging and MR spectroscopic imaging

PURPOSE

To determine the role that magnetic resonance (MR) imaging and MR spectroscopic imaging findings obtained at the time of diagnosis play in the progression of disease in patients whose prostate cancer is being managed with active surveillance and to compare the role of these findings with the role of transrectal ultrasonography (US) findings.

MATERIALS AND METHODS

The institutional review board approved this HIPAA-compliant retrospective study, and informed consent was obtained from all patients whose records were to be entered into the research database. All patients who had prostate cancer managed with active surveillance and who had undergone both MR imaging and MR spectroscopic imaging of the prostate and transrectal US at time of diagnosis were identified. Two urologists blinded to the clinical outcome in these patients independently reviewed and dichotomized the MR imaging report and the MR spectroscopic imaging report as normal or suggestive of malignancy. One experienced urologist performed all US examinations that were then dichotomized similarly. Uni- and multivariate (with use of standard clinical variables) Cox models were fitted to assess time to cancer progression, defined as Gleason score upgrading, prostate-specific antigen velocity of more than 0.75 (microg x L(-1))/y, or initiation of treatment more than 6 months after diagnosis.

RESULTS

The final cohort included 114 patients with a median follow-up of 59 months. Patients with a lesion that was suggestive of cancer at MR imaging had a greater risk of the Gleason score being upgraded at subsequent biopsy (hazard ratio, 4.0; 95% confidence interval: 1.1, 14.9) than did patients without such a lesion. Neither MR spectroscopic imaging nor transrectal US could be used to predict cancer progression.

CONCLUSION

Abnormal prostate MR imaging results suggestive of cancer may confer an increased risk of Gleason score upgrade at subsequent biopsy. Although expensive, prostate MR imaging may help in counseling potential candidates about active surveillance.

Effect of dutasteride on the risk of prostate cancer

BACKGROUND

We conducted a study to determine whether dutasteride reduces the risk of incident prostate cancer, as detected on biopsy, among men who are at increased risk for the disease.

METHODS

In this 4-year, multicenter, randomized, double-blind, placebo-controlled, parallel-group study, we compared dutasteride, at a dose of 0.5 mg daily, with placebo. Men were eligible for inclusion in the study if they were 50 to 75 years of age, had a prostate-specific antigen (PSA) level of 2.5 to 10.0 ng per milliliter, and had had one negative prostate biopsy (6 to 12 cores) within 6 months before enrollment. Subjects underwent a 10-core transrectal ultrasound-guided biopsy at 2 and 4 years.

RESULTS

Among 6729 men who underwent a biopsy or prostate surgery, cancer was detected in 659 of the 3305 men in the dutasteride group, as compared with 858 of the 3424 men in the placebo group, representing a relative risk reduction with dutasteride of 22.8% (95% confidence interval, 15.2 to 29.8) over the 4-year study period (P<0.001). Overall, in years 1 through 4, among the 6706 men who underwent a needle biopsy, there were 220 tumors with a Gleason score of 7 to 10 among 3299 men in the dutasteride group and 233 among 3407 men in the placebo group (P=0.81). During years 3 and 4, there were 12 tumors with a Gleason score of 8 to 10 in the dutasteride group, as compared with only 1 in the placebo group (P=0.003). Dutasteride therapy, as compared with placebo, resulted in a reduction in the rate of acute urinary retention (1.6% vs. 6.7%, a 77.3% relative reduction). The incidence of adverse events was similar to that in studies of dutasteride therapy for benign prostatic hyperplasia, except that in our study, as compared with previous studies, the relative incidence of the composite category of cardiac failure was higher in the dutasteride group than in the placebo group (0.7% [30 men] vs. 0.4% [16 men], P=0.03).

CONCLUSIONS

Over the course of the 4-year study period, dutasteride reduced the risk of incident prostate cancer detected on biopsy and improved the outcomes related to benign prostatic hyperplasia. (ClinicalTrials.gov number, NCT00056407.)

Testing the most stringent criteria for selection of candidates for active surveillance in patients with low-risk prostate cancer

OBJECTIVE

To test the ability of two of the most stringent criteria used to identify patients with low-risk prostate cancer suitable for active surveillance (AS) to correctly exclude patients with unfavourable prostate cancer characteristics.

PATIENTS AND METHODS

The study included 874 consecutive patients treated with radical prostatectomy (RP). We selected patients who could have been selected for AS according to the van den Bergh et al. and the Carter et al. criteria. We analysed the rates of advanced disease in these patients, defined as presence of either extracapsular extension (ECE), seminal vesicle invasion (SVI), lymph node invasion (LNI) and Gleason sum of 8-10 or 7-10.

RESULTS

Of 874 patients, 85 (9.7%) and 61 (6.9%) patients, respectively, qualified for AS according to the tested criteria. Within the van den Bergh et al. candidates, 5.9, 1.2, 1.2 and 1.2% of patients, respectively, showed ECE, SVI, LNI and high-grade Gleason sum 8-10 at pathology. Within the Carter et al. candidates, 3.3, 0, 3.3 and 0% of patients, respectively, showed ECE, SVI, LNI and high-grade Gleason sum 8-10. The cumulative rate of unfavourable characteristics was 7.1 and 3.3%. The rate increased to 28.2 and 27.9%, respectively, when Gleason sum 7 was considered as an unfavourable prostate cancer.

CONCLUSIONS

The use of the strictest criteria for AS inclusion identified 7-10% of the men in our cohort of men undergoing RP, as men that would have been eligible for AS. Among this small proportion, between 3.3 and 7.1% of patients harboured unfavourable prostate cancer characteristics. The clinical implications of these misclassification rates remain to be determined.

Short-term outcomes of the prospective multicentre 'Prostate Cancer Research International: Active Surveillance' study

OBJECTIVE

To evaluate the short-term outcomes of the prospective international Prostate Cancer Research International: Active Surveillance ('PRIAS') study (Dutch Trial Register NTR1718), as active surveillance (AS) for early prostate cancer might provide a partial solution to the current overtreatment dilemma in this disease.

PATIENTS AND METHODS

The first 500 (of >950) participants with asymptomatic T1c/T2 prostate cancer, with a prostate-specific antigen (PSA) level of < or =10.0 ng/mL, a PSA density of <0.2 ng/mL/mL, a Gleason score of < or =3 + 3 = 6, and one or two positive biopsy cores, were analysed. The follow-up protocol consisted of frequent PSA measurements, digital rectal examinations, and standard repeat biopsies (the first after 1 year). The primary outcome is survival free of active therapy; the secondary endpoints are reasons for stopping AS, findings in 1-year repeat biopsies, and outcomes after radical prostatectomy (RP).

RESULTS

Patients were included between December 2006 and July 2008. The median (25-75th percentile) follow-up after diagnosis was 1.02 (0.6-1.5) years. The 2-year survival rate free from active therapy was 73%. Of the 82 men who changed to active therapy during the follow-up, 68 (83%) did so based on the protocol. Of the 261 repeat biopsies available for analysis, 90 (34%) showed no cancer, while 57 (22%) showed a Gleason score of >6 or more than two positive biopsy cores. There was a relatively unfavourable PSA doubling time of 0-10 years in 53% (102/194) and 62% (33/53) of men with favourable and unfavourable re-biopsy results, respectively. After RP, four of 24 (17%) men had T3 disease and 12 (50%) had a Gleason score of >6.

CONCLUSION

AS seems feasible, but mortality outcomes are unknown. A strict follow-up protocol including standard 1-year repeat biopsies resulted in a quarter of men stopping AS after 2 years.

Pathological upgrading and up staging with immediate repeat biopsy in patients eligible for active surveillance

PURPOSE

Active surveillance with selective delayed intervention is a treatment regimen used in patients with low risk prostate cancer. Decision making is based on pretreatment prostate specific antigen, clinical stage and prostate biopsy results. We reviewed our experience with immediate repeat biopsy in patients eligible for active surveillance with selective delayed intervention.

MATERIALS AND METHODS

A retrospective review was done of the records of consecutive patients who underwent repeat biopsy within 3 months of a first positive biopsy from March 2002 to June 2007. Patients were considered eligible if they had prostate specific antigen less than 10 ng/ml, clinical stage T2a or less, Gleason pattern 3 or less, 3 or fewer positive cores and no single core with 50% or greater cancer involvement.

RESULTS

A total of 104 patients met eligibility criteria. Of the 104 repeat biopsies performed 27 (26%) were negative, 59 (57%) had a Gleason score of 6 or less and 17 (16%) had a Gleason score of 7. One patient had a Gleason score of 9, while 10 of 104 (10%) had greater than 3 cores involved on repeat biopsy and 12 (12%) had 50% or greater involvement of at least 1 core. Of 104 cases (27%) 28 were upgraded and/or up staged. Treated cases that were upgraded and/or up staged were more likely to show higher pathological stage and grade at radical prostatectomy than those that were not (p = 0.003 and p = 0.001, respectively).

CONCLUSIONS

Immediate repeat biopsy in cases of active surveillance with selective delayed intervention resulted in 27% being upgraded or up staged and those were more likely to show higher grade and stage disease at radical prostatectomy. We recommend repeat biopsy because it improved our discrimination of who are the best candidates for active surveillance with selective delayed intervention.