Pathological Features After Radical Prostatectomy in Potential Candidates for Active Monitoring

Pathological and oncological features of Korean prostate cancer patients eligible for active surveillance: analysis from the K-CaP registry

Background

A web-based multicenter Korean Prostate Cancer Database (K-CaP) was established to provide urologists with information on Korean prostate cancer (PCa) patients treated with radical prostatectomy (RP). We utilized the K-CaP registry to identify pathological features and oncological outcomes of Korean PCa patients eligible for active surveillance (AS).

Methods

The K-CaP registry consisted of 6415 patients who underwent RP from May 2001 to April 2013 at five institutions. Preoperative clinicopathological data were collected to identify patients who were eligible for at least one contemporary AS protocol. Patients who had received neoadjuvant androgen deprivation therapy or a 5α-reductase inhibitor, who had <10 total biopsy cores, or who had incomplete data were excluded. Biochemical recurrence (BCR) was defined as prostate-specific antigen (PSA) level ≥0.2 ng/ml following RP.

Results

A total of 560 patients were identified, and the median follow-up period was 52.0 (interquartile range, 39.0-67.3) months. Pathologically insignificant PCa, defined as organ-confined disease with Gleason score ≤6 was observed in 314 (56.1%) patients. Pathological upgrading (Gleason score ≥7) and upstaging (≥pT3) were observed in 237 (42.3%) and 75 (13.4%) patients, respectively. Unfavorable disease (extracapsular extension, seminal vesicle invasion, or Gleason score ≥8) was observed in 85 (15.2%) patients. PSA density ≤0.2 ng/ml/cc and maximal single core involvement ≤20% were revealed as independent preoperative predictors of pathologically insignificant PCa.

Conclusion

Contemporary Western AS protocols unreliably predict pathologically insignificant PCa in Korean men. Korean men may harbor more aggressive PCa features than Western men, and thus, a more stringent AS protocol is needed.

Pathologic correlation of transperineal in-bore 3-Tesla magnetic resonance imaging-guided prostate biopsy samples with radical prostatectomy specimen

PURPOSE

To determine the accuracy of in-bore transperineal 3-Tesla (T) magnetic resonance (MR) imaging-guided prostate biopsies for predicting final Gleason grades in patients who subsequently underwent radical prostatectomy (RP).

METHODS

A retrospective review of men who underwent transperineal MR imaging-guided prostate biopsy (tpMRGB) with subsequent radical prostatectomy within 1 year was conducted from 2010 to 2015. All patients underwent a baseline 3-T multiparametric MRI (mpMRI) with endorectal coil and were selected for biopsy based on MR findings of a suspicious prostate lesion and high degree of clinical suspicion for cancer. Spearman correlation was performed to assess concordance between tpMRGB and final RP pathology among patients with and without previous transrectal ultrasound (TRUS)-guided biopsies.

RESULTS

A total of 24 men met all eligibility requirements, with a median age of 65 years (interquartile range [IQR] 11.7). The median time from biopsy to RP was 85 days (IQR 50.5). Final pathology revealed Gleason 3 + 4 = 7 in 12 patients, 4 + 3 = 7 in 10 patients, and 4 + 4 = 8 in 2 patients. A strong correlation (ρ: +0.75, p < 0.001) between tpMRGB and RP results was observed, with Gleason scores concordant in 17 cases (71%). 16 of the 24 patients underwent prior TRUS biopsies. Subsequent tpMRGB revealed Gleason upgrading in 88% of cases, which was concordant with RP Gleason scores in 69% of cases (ρ: +0.75, p < 0.001).

CONCLUSION

Final Gleason scores diagnosed by tpMRGB at 3-T correlate strongly with final RP surgical pathology. This may facilitate prostate cancer diagnosis, particularly in patients with negative or low-grade TRUS biopsy results in whom clinically significant cancer is suspected or detected on mpMRI.

Use of mpMRI in active surveillance for localized prostate cancer

INTRODUCTION

In an effort to limit prostate cancer (PCa) overdiagnosis and overtreatment, which have occurred in response to widespread prostate specific antigen testing, numerous strategies aimed at improved risk stratification of patients with PCa have evolved. Multiparametric magnetic resonance imaging (MRI) is being used in concert with prostate specific antigen testing and prostate biopsies to improve sensitivity and specificity of these tests. There are limited data on how multiparametric MRI can be incorporated into active surveillance (AS) protocols.

EVIDENCE ACQUISITION

A PubMed literature search of available English language publications on PCa, AS, and MRI was conducted. Appropriate articles were selected and included for review. Bibliographies were also used to expand our search.

EVIDENCE SYNTHESIS

Data from 41 studies were reviewed. AS inclusion criteria and protocols varied among studies, as did indications for use of MRI. Technological improvements are briefly highlighted. Studies are broadly categorized and discussed according to the role of MRI in patient selection, disease staging, and monitoring in AS protocols.

CONCLUSIONS

Although improvements in MRI technology have been useful for biopsy guidance and in the diagnosis and staging of PCa, this literature search demonstrates that more prospective research is needed, specifically regarding how this promising technology can be incorporated into AS protocols.

[Active surveillance for low-risk prostate cancer]

Autopsy studies have confirmed the high prevalence of latent prostate cancer; however, only a certain portion of patients require definite treatment. Active surveillance is one of the treatment options which, according to national and international guidelines, should be offered to patients with newly diagnosed low-risk prostate cancer. Prostate cancer-specific survival is high in these patients; therefore, curative treatment, such as radical prostatectomy, external beam radiotherapy and brachytherapy may be initially deferred in order to avoid therapy-related side effects. In order to qualify for active surveillance, strict inclusion criteria have to be met; nevertheless, the reliable identification of low-risk prostate cancer patients is not always possible. Patients under active surveillance are followed up regularly with prostate-specific antigen (PSA) testing, digital rectal examination (DRE) and repeat prostate biopsies. Due to the heterogeneity of primary prostate tumors precise molecular diagnostic techniques could allow individualized treatment strategies in the future.

[Active surveillance of low risk prostate cancer]

In Europe prostate cancer is one of the most common cancers among men. The diagnostics always include a control of the prostate-specific antigen (PSA) level and examination of a representative tissue sample from the prostate. With these findings it is possible to evaluate the degree of progression of the cancer and its prognosis. Several treatment options for localized prostate cancer are given by national and international guidelines including radical prostatectomy, percutaneous radiation therapy, or brachytherapy and surveillance of the cancer with optional treatment at a later stage. For the latter treatment option, known as active surveillance, strict criteria have to be met. The advantage of active surveillance is that only patients with progressive cancer are subjected to radical therapy. Patients with very slow or non-progressing cancer do not have to undergo therapy and thus do not have to suffer from the side effects. The basic idea behind active surveillance is that some cancers will not progress to a stage that requires treatment within the lifetime of the patient and therefore do not require treatment at all. Unfortunately the criteria for active surveillance are not definitive enough at the current time leading only to a delay in effective treatment for many patients. The surveillance strategy has without doubt a high significance among the treatment options for prostate cancer; however, at the current time it lacks reliable indicators for a certain prognosis. Therefore, patients must be informed in detail about the advantages and disadvantages of active surveillance.

Disease reclassification risk with stringent criteria and frequent monitoring in men with favourable-risk prostate cancer undergoing active surveillance

OBJECTIVES

To determine the frequency of disease reclassification and to identify clinicopathological variables associated with it in patients with favourable-risk prostate cancer undergoing active surveillance (AS).

PATIENTS AND METHODS

We assessed 191 men, selected by what may be the most stringent criteria used in AS studies yet conducted, who were enrolled in a prospective cohort AS trial. Clinicopathological characteristics were analysed in a multivariate Cox proportional hazards regression model. Key features were an extended biopsy with a single core positive for Gleason score (GS) 3 + 3 (<3 mm) or 3 + 4 (<2 mm) and a prostate-specific antigen (PSA) level <4 ng/mL (adjusted for prostate volume). Biopsies were repeated every 1-2 years and clinical evaluations every 6 months. Disease was reclassified when PSA level increased by 30% from baseline, or when biopsy tumour length increased beyond the enrolment criteria, more than one positive core was detected or any grade increased to a dominant 4 pattern or any 5 pattern.

RESULTS

Disease was reclassified in 32 patients (16.8%) including upgrading to GS 4 + 3 in five patients (2.6%). The median (interquartile range) follow-up time among survivors was 3 (1.9-4.6) years. Overall, 13 of the 32 (40.6%) had incremental increases in GS. Tumour length (hazard ratio 2.95, 95% confidence interval [CI] 1.34-6.46; P = 0.007) and older age (hazard ratio 1.05, 95% CI 1.00-1.09; P = 0.05) were identified as significant and marginally significant predictors of disease reclassification, respectively. Disease remained stable in 83.2% of patients.

CONCLUSION

The need persists for improvements in risk stratification and predictive indicators of cancer progression.

Final pathohistology after radical prostatectomy in patients eligible for active surveillance (AS)

PURPOSE

The aim of the current study was to determine in retrospect how many of a group of patients who underwent radical prostatectomy were correctly classified with an insignificant prostate carcinoma by means of preoperative diagnostics. Furthermore, we are aiming at finding preoperative parameters which predict an insignificant prostate carcinoma with higher accuracy. The current inclusion parameters of AS will be verified with regard to their reliability, and we will discuss the possibility of improving their prediction accuracy.

METHODS

We examined the data of 308 consecutive patients who were diagnosed with a clinically insignificant prostate carcinoma and therefore would be suited for AS, but opted for a radical prostatectomy. According to the literature(1), the following inclusion criteria were chosen for our evaluation: a proven prostate carcinoma, detected by either ultrasonically guided transrectal core needle biopsy (cT1c) with at least six obtained samples and with a maximum of two positive samples on one side and a less than a 50 % tumor rate per sample, or a 5 % or lower tumor rate found in the tissue obtained by transurethral prostate resection (cT1a). The PSA value in all cases was below 10 ng/ml and the Gleason Score ≤6. The probability of a preoperative "undergrading" or "understaging" was determined as a function of preoperative parameters like Gleason Score, PSA value, the number of collected samples and positive samples obtained by core needle biopsy, prostate volume, and PSA density. Based on the available preoperative data, we developed and tested several regression models for the identification of independent factors for upgrading and upstaging.

RESULTS

Within the examined patient population, 232 of 308 patients (75 %) were, according to their final prostate histology, diagnosed with a stage ≥pT2b prostate carcinoma. Eight percentage of the patients who had undergone surgery had a stage ≥pT3a carcinoma, and 118 of 308 (38 %) had a Gleason Score of 6 or higher. Positive lymph nodes and an infiltration of the seminal vesicle each occurred in 1 % of the cases. Histopathologic positive margins of resection existed in 33 of 308 patients (11 %). Independent factors for upgrading and upstaging a prostate volume of <50 ml and a preoperative Gleason Score of ≤6 were identified.

CONCLUSION

The presented results show that the current inclusion criteria for AS are insufficient. For many patients, the beginning of the necessary therapy is delayed. According to our data, the prostate volume, the preoperative Gleason Score, and the number of positive samples obtained by transrectal core needle biopsy have the highest predictive power with regard to aggressiveness and expansion of the tumor. Despite the consideration of all these preoperative parameters, the differentiation of the prostate carcinomas was underrated in a third of all cases. The expansion of the tumor within the prostate was underrated even in three fourths of the cases.

Transurethral resection of the prostate for patients with Gleason score 6 prostate cancer and symptomatic prostatic enlargement: a risk-adaptive strategy for the era of active surveillance

OBJECTIVE

To investigate whether transurethral resection of the prostate can be used as both (i) treatment for symptomatic prostatic enlargement in patients with prostate cancer and (ii) a risk-adaptive strategy for reducing prostate-specific antigen levels and broadening the indications of active surveillance.

METHODS

We retrospectively reviewed data of 3680 patients who underwent prostate biopsies at a single institution (March 2006 to January 2012). Of 529 men who had Gleason score 6 prostate cancer and were ineligible for active surveillance, 86 (16.3%) underwent transurethral resection of the prostate for symptomatic prostatic enlargement. We assessed how changes in prostate-specific antigen and prostate-specific antigen density influenced the eligibility for active surveillance and the outcome of subsequent therapy. The following active surveillance criteria were used: prostate-specific antigen ≤ 10 ng/ml, prostate-specific antigen density ≤ 0.15, positive cores ≤ 3 and single core involvement ≤ 50%.

RESULTS

The median age, pre-operative prostate-specific antigen and prostate volume were 71 years, 6.95 ng/ml, and 45.8 g, respectively. In 82.6% (71/86) of analyzed cases, ineligibility for active surveillance had resulted from elevated prostate-specific antigen level or prostate-specific antigen density. With a median resection of 16.5 g, transurethral resection of the prostate reduced the percentage of prostate-specific antigen and the percentage of prostate-specific antigen density by 34.5 and 50.0%, respectively, making 81.7% (58/71) of the patients eligible for active surveillance. Prostate-specific antigen level remained stabilized in all (21/21) patients maintained on active surveillance without disease progression during the median follow-up of 50.6 months. Among patients who underwent radical prostatectomy, 96.7% (29/30) exhibited localized disease.

CONCLUSIONS

Risk-adaptive transurethral resection of the prostate may prevent overtreatment and allay prostate-specific antigen-associated anxiety in patients with biopsy-proven low-grade prostate cancer and elevated prostate-specific antigen. Additional benefits include voiding symptom improvement and the avoidance of curative therapy's immediate side effects.

Perspectives on the clinical management of localized prostate cancer

If cure is necessary, is it possible and if cure is possible, is it necessary?’

-Willet F. Whitmore

Defined broadly, prostate cancer has two states: An indolent histological manifestation of a locally proliferative and invasive process or a clinically relevant, potentially lethal disease. Likewise, the management of clinically localized prostate cancer must address two questions: what sort of disease is this and what needs to be done.

Active surveillance versus surgery for low risk prostate cancer: a clinical decision analysis

PURPOSE

We assessed the effect of age, health status and patient preferences on outcomes of surgery vs active surveillance for low risk prostate cancer.

MATERIALS AND METHODS

We used Monte Carlo simulation of Markov models of the life courses of 200,000 men diagnosed with low risk prostate cancer and treated with surveillance or radical prostatectomy to calculate quality adjusted life expectancy, life expectancy, prostate cancer specific mortality and years of treatment side effects, with model parameters derived from the literature. We simulated outcomes for men 50 to 75 years old with poor, average or excellent health status (50%, 100% and 150% of average life expectancy, respectively). Sensitivity of outcomes to uncertainties in model parameters was tested.

RESULTS

For 65-year-old men in average health, surgery resulted in 0.3 additional years of life expectancy, 1.6 additional years of impotence or incontinence and a 4.9% decrease in prostate cancer specific mortality compared to surveillance, for a net difference of 0.05 fewer quality adjusted life years. Increased age and poorer baseline health status favored surveillance. With greater than 95% probability, surveillance resulted in net benefits compared to surgery for age older than 74, 67 and 54 years for men in excellent, average and poor health, respectively. Patient preferences toward life under surveillance, biochemical recurrence of disease, treatment side effects and future discount rate affected optimal management choice.

CONCLUSIONS

Older men and men in poor health are likely to have better quality adjusted life expectancy with active surveillance. However, specific individual preferences impact optimal choices and should be a primary consideration in shared decision making.

Association of prostate cancer risk alleles with unfavourable pathological characteristics in potential candidates for active surveillance

OBJECTIVE

• To assess whether the carrier status of 35 risk alleles for prostate cancer (CaP) is associated with having unfavourable pathological features in the radical prostatectomy specimen in men with clinically low risk CaP who fulfil commonly accepted criteria as candidates for active surveillance.

PATIENTS AND METHODS

• We studied men of European ancestry with CaP who fulfilled the commonly accepted clinical criteria for active surveillance (T1c, prostate-specific antigen <10 ng/mL, biopsy Gleason ≤6, three or fewer positive cores, ≤50% tumour involvement/core) but instead underwent early radical prostatectomy. • We genotyped these men for 35 CaP risk alleles. We defined 'unfavourable' pathological characteristics to be Gleason ≥7 and/or ≥ pT2b in their radical prostatectomy specimen.

RESULTS

• In all, 263 men (median age 60 [46-72] years) fulfilled our selection criteria for active surveillance, and 58 of 263 (22.1%) were found to have 'unfavourable' pathological characteristics. • The frequencies of three CaP risk alleles (rs1447295 [8q24], P= 0.004; rs1571801 [9q33.2], P= 0.03; rs11228565 [11q13], P= 0.02) were significantly higher in men with 'unfavourable' pathological characteristics. • Two other risk alleles were proportionately more frequent (rs10934853 [3q21], P= 0.06; rs1859962 [17q24], P= 0.07) but did not achieve nominal statistical significance. • Carriers of any one of the significantly over-represented risk alleles had twice the likelihood of unfavourable tumour features (P= 0.03), and carriers of any two had a sevenfold increased likelihood (P= 0.001). • Receiver-operator curve analysis demonstrated an area under the curve of 0.66, suggesting that the number of single nucleotide polymorphisms carried provided discrimination between men with 'favourable' and 'unfavourable' tumour features in their prostatectomy specimen.

CONCLUSION

• In potential candidates for active surveillance, certain CaP risk alleles are more prevalent in patients with 'unfavourable' pathological characteristics in their radical prostatectomy specimen.

[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.

Active surveillance compared with initial treatment for men with low-risk prostate cancer: a decision analysis

CONTEXT

In the United States, 192,000 men were diagnosed as having prostate cancer in 2009, the majority with low-risk, clinically localized disease. Treatment of these cancers is associated with substantial morbidity. Active surveillance is an alternative to initial treatment, but long-term outcomes and effect on quality of life have not been well characterized.

OBJECTIVE

To examine the quality-of-life benefits and risks of active surveillance compared with initial treatment for men with low-risk, clinically localized prostate cancer.

DESIGN AND SETTING

Decision analysis using a simulation model was performed: men were treated at diagnosis with brachytherapy, intensity-modulated radiation therapy (IMRT), or radical prostatectomy or followed up by active surveillance (a strategy of close monitoring of newly diagnosed patients with serial prostate-specific antigen measurements, digital rectal examinations, and biopsies, with treatment at disease progression or patient choice). Probabilities and utilities were derived from previous studies and literature review. In the base case, the relative risk of prostate cancer-specific death for initial treatment vs active surveillance was assumed to be 0.83. Men incurred short- and long-term adverse effects of treatment.

PATIENTS

Hypothetical cohorts of 65-year-old men newly diagnosed as having clinically localized, low-risk prostate cancer (prostate-specific antigen level <10 ng/mL, stage ≤T2a disease, and Gleason score ≤6).

MAIN OUTCOME MEASURE

Quality-adjusted life expectancy (QALE).

RESULTS

Active surveillance was associated with the greatest QALE (11.07 quality-adjusted life-years [QALYs]), followed by brachytherapy (10.57 QALYs), IMRT (10.51 QALYs), and radical prostatectomy (10.23 QALYs). Active surveillance remained associated with the highest QALE even if the relative risk of prostate cancer-specific death for initial treatment vs active surveillance was as low as 0.6. However, the QALE gains and the optimal strategy were highly dependent on individual preferences for living under active surveillance and for having been treated.

CONCLUSIONS

Under a wide range of assumptions, for a 65-year-old man, active surveillance is a reasonable approach to low-risk prostate cancer based on QALE compared with initial treatment. However, individual preferences play a central role in the decision whether to treat or to pursue active surveillance.

Periprostatic fat correlates with tumour aggressiveness in prostate cancer patients

STUDY TYPE

Prognostic (case series).

LEVEL OF EVIDENCE

4. What's known on the subject? and What does the study add? Nowadays more and more publications have been published about the topic prostate cancer aggressiveness and obesity with mixed results. However, most of the publications used the BMI as a marker for obesity, while the most metabolic active fat is the visceral fat. To learn more about these relations we measured and used the visceral fat in our paper.

OBJECTIVE

To examine if the periprostatic fat measured on computed tomography (CT) correlates with advanced disease we examined patients who received radiotherapy for localized prostate cancer. Several USA reports found a positive association between obesity and prostate cancer aggressiveness. However, in recent European studies these conclusions were not confirmed. Studies concerning this issue have basically relied on body mass index (BMI), as a marker of general obesity. Visceral fat, however, is the most metabolically active and best measured on CT.

PATIENTS AND METHODS

In 932 patients, who were treated with external radiotherapy (N=311) or brachytherapy (N=621) for their T1-3N0M0 prostate cancer, different fat measurements (periprostatic fat, subcutaneous fat thickness) were performed on a CT. Associations between the different fat measurements and risk of having high-risk (according to Ash et al., PSA>20 or Gleason score≥8 or T3) disease was measured.

RESULTS

The median age (IQR) was 67.0 years (62.0-71.0) and median BMI (IQR) was 25.8 (24.2-28.3). Logistic regression analyses, adjusted for age, revealed a significant association between periprostatic fat density (PFD) and risk of having a high risk disease. (Odds ratio [95% CI] 1.06 [1.04-1.08], P<0.001)

CONCLUSION

Patients with a higher PFD had more often aggressive prostate cancer.

Treatment outcomes of radical prostatectomy in potential candidates for 3 published active surveillance protocols

OBJECTIVES

To examine the treatment outcomes of men who would have been eligible for active surveillance (AS) but underwent immediate radical retropubic prostatectomy (RRP). AS protocols are designed to spare the potential morbidity of treatment to patients with low-risk prostate cancer (PCa).

METHODS

From a prospective RRP database, we evaluated the tumor features and treatment outcomes for men who would have met 1 of 3 published AS criteria: (1) clinically localized disease, Gleason < or = 7, and no significant comorbidities (Patel et al, J Urol. 2004;171:1520-1524) (2) T1b-T2b N0M0 disease, Gleason < or = 7, and prostate-specific antigen < or = 15 ng/mL (Choo R et al. J Urol. 2002;167:1664-1669), or (3) T1c PCa (Mohler JL et al. World J Urol. 1997;15:364-368.).

RESULTS

3959, 3536, and 2330 RRP patients, respectively, would have met these AS criteria. At surgery, 3%-4% had a Gleason score of 8-10, 16%-19% had positive surgical margins, 15%-18% had extracapsular tumor extension, 3%-5% had seminal vesicle invasion, and 0.4%-1% had lymph node metastasis. The 5-year progression-free survival rate ranged from 84%-89%. Metastasis occurred in 0.1%-1.2%, and 0.1%-0.9% died of PCa. On multivariate analysis, Gleason score > 6 was the strongest predictor of biochemical progression.

CONCLUSIONS

A substantial proportion of men who might have been considered potential AS candidates had aggressive tumor features at RRP and/or progression. Biopsy Gleason score > 6 was the strongest predictor of adverse outcomes, highlighting the importance of limiting AS to patients with Gleason < or = 6. Overall, the accurate identification of patients with truly indolent PCa at the time of diagnosis remains challenging.

Radical prostatectomy findings in patients predicted to have low-volume/low-grade prostate cancer diagnosed by extended-core biopsies: an analysis of volume and zonal distribution of tumour foci

OBJECTIVE

To measure total tumour volume (TTV) and dominant TV (DTV) in radical prostatectomy (RP) specimens from patients predicted to have low-volume, low-grade (LV/LG) prostate cancer, as this entity can be predicted from biopsy findings and prostate-specific antigen (PSA) level, but tumour under-sampling remains a challenge in active surveillance programmes.

PATIENTS AND METHODS

This was a retrospective study from an academic centre, of men with prostate cancer treated from 2000 to 2007, with a PSA level of <10 ng/mL and one core of cancer from an extended scheme showing either Gleason score (GS) 3 + 3 of <3.0 mm or 3 + 4 of <2.0 mm. All men had RP, and the TTV, DTV, tumour location, pathological GS and stage were measured.

RESULTS

Of 3055 RPs, 66 (2.1%) met the inclusion criteria. The core with cancer was from a sextant and alternative site in 26 (39%) and 40 (61%) patients, respectively. A pathological GS 3 + 3 or 3 + 4 was assigned to 94%, while 6% were GS > or = 4 + 3; all 66 tumours were organ-confined. The median (range) TTV and DTV were 0.15 (0.0008-5.06) and 0.14 (0.0008-5.04) mL, respectively. The median number of tumour foci was 3 (1-7), being unifocal in 17/66 (26%) and multifocal in 49/66 (74%). The transition zone was involved in 29% of unifocal and 71% of multifocal tumours. Of all 66 patients, the TTV was <0.5 mL in 47 (71%), and of 59 patients with biopsy GS 3 + 3, 33 (56%) had a TTV of <0.5 mL and pathological GS 3 + 3. Of 19 patients with a TTV of > or =0.5 mL, the median TTV was 1.06 (0.51-5.05) mL, with tumour foci of transition zone origin in 16 (84%). The study was limited by its retrospective design and small sample size.

CONCLUSIONS

Using conservative selection criteria for predicting LV/LG cancer, RP specimens showed organ-confined disease in all cases, upgrading to GS > or = 4 + 3 in 6%, and TTV <0.5 mL in 71% of cases. The transition zone is a common location of under-sampled disease.

Assessment of pathological prostate cancer characteristics in men with favorable biopsy features on predominantly sextant biopsy

BACKGROUND

The rate of insignificant prostate cancer (IPCa) is increasing.

OBJECTIVES

To examine three end points in patients with a single, positive core and no high-grade prostate cancer (PCa) at biopsy, namely (1) rate of clinical IPCa at radical prostatectomy (RP), defined as organ-confined PCa with a Gleason score of 6 or lower and tumor volume<0.5 cc; (2) rate of pathologically unfavorable PCa at RP (Gleason 7-10 or non-organ-confined disease); and (3) ability to predict either insignificant or unfavorable PCa at RP.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective analysis of 209 men with one positive biopsy core showing Gleason 6 or lower.

MEASUREMENTS

: Detailed clinical and RP data were used in multivariable logistic regression models. Their bias-corrected accuracy estimates were quantified using the area under the curve (AUC) method.

RESULTS AND LIMITATIONS

At RP, IPCa was present in 28 patients (13.4%) and pathologically unfavorable PCa, defined as Gleason 7 or higher or non-organ-confined PCa, was reported in 70 (33.5%) of 209 men; when Gleason 8 or higher or non-organ-confined PCa was considered, the proportion fell to 11%. Our multivariable models predicting different categories of pathologically unfavorable PCa at RP had an accuracy rate between 56% and 68% for predicting IPCa at RP versus 65.1% to 66.1% and 61.7% for the IPCa nomograms of Kattan et al and Nakanishi et al, respectively. Our data are not applicable to screening because they originate from a referral population.

CONCLUSIONS

Despite highly favorable biopsy features, between 11% and 33% of men had unfavorable PCa at RP and only a minority (13.4%) had pathologically confirmed IPCa. Neither clinically insignificant nor pathologically unfavorable features could be predicted with sufficient accuracy for clinical decision making.