Conditional probability of reclassification in an active surveillance program for prostate cancer

Upgrading of Grade Group 1 Prostate Cancer at Prostatectomy: Germline Risk Factors in a Prospective Cohort

BACKGROUND

Localized prostate tumors show significant spatial heterogeneity, with regions of high-grade disease adjacent to lower grade disease. Consequently, prostate cancer biopsies are prone to sampling bias, potentially leading to underestimation of tumor grade. To study the clinical, epidemiologic, and molecular hallmarks of this phenomenon, we conducted a prospective study of grade upgrading: differences in detected prostate cancer grade between biopsy and surgery.

METHODS

We established a prospective, multi-institutional cohort of men with grade group 1 (GG1) prostate cancer on biopsy who underwent radical prostatectomy. Upgrading was defined as detection of GG2+ in the resected tumor. Germline DNA from 192 subjects was subjected to whole-genome sequencing to quantify ancestry, pathogenic variants in DNA damage response genes, and polygenic risk.

RESULTS

Of 285 men, 67% upgraded at surgery. PSA density and percent of cancer in pre-prostatectomy positive biopsy cores were significantly associated with upgrading. No assessed genetic risk factor was predictive of upgrading, including polygenic risk scores for prostate cancer diagnosis.

CONCLUSIONS

In a cohort of patients with low-grade prostate cancer, a majority upgraded at radical prostatectomy. PSA density and percent of cancer in pre-prostatectomy positive biopsy cores portended the presence of higher-grade disease, while germline genetics was not informative in this setting. Patients with low-risk prostate cancer, but elevated PSA density or percent cancer in positive biopsy cores, may benefit from repeat biopsy, additional imaging or other approaches to complement active surveillance.

IMPACT

Further risk stratification of patients with low-risk prostate cancer may provide useful context for active surveillance decision-making.

The impact of age on prostate cancer progression and quality of life in active surveillance patients

Objectives

To evaluate the impact of age on overall survival (OS), freedom from distant metastasis (FDM), rates of therapeutic intervention (TI), and quality of life (QOL) in active surveillance (AS) prostate cancer patients.

Materials and methods

Three hundred and five consecutive, prospectively evaluated AS patients who underwent a staging transperineal template‐guided mapping biopsy (TTMB) prior to enrollment on AS were evaluated and stratified by age. Evaluated outcomes included OS, FDM, TI, and QOL to include urinary, bowel, sexual function, and depression. Post void residual (PVR) urine measurements were also followed. Repeat biopsy was based on PSA kinetics, abnormal digital rectal examination or patient preference.

Results

Of the 305 patients, 290 (95.1%) were Gleason 3 + 3 and 15 patients (4.9%) were Gleason 3 + 4. The median follow‐up was 5.5 years (range 1‐14 years). At 10 years, TI was 0%, 1.0%, and 11.4% for patients ≤59, 60‐69, and ≥70 years of age (P < .001). No patient has developed distant metastasis. The median time to TI was 4.71 years. No statistical differences in urinary function, bowel function, or depression were noted. Potency preservation was dependent on patient age.

Conclusion

Within the confines of the follow‐up of our series, younger patients were less likely to proceed to therapeutic intervention. In addition, patient age did not adversely impact QOL outcomes.

Prostate cancer adverse pathology reclassification in patients undergoing active surveillance in a long-term follow-up series

BACKGROUND

Active surveillance (AS) has become a valid option for patients with a very low risk of prostate cancer (PC) with a widespread application. There are still a few series, with a medium follow-up longer than 5 years, reporting data on pathological upgrading. The objective is to evaluate the changes in surveillance biopsies of patients with low-risk PC in a long-term follow-up and determine if a longer stay in AS could involve worse pathological findings.

MATERIALS AND METHODS

A retrospective analysis of our institutional database of patients with PC undergoing AS during 2004 to 2018 was performed. The inclusion criteria were prostate-specific antigen (PSA) ≤ 10 ng/mL, Gleason grade 1 and T1c/T2a. Patients were assessed by serum PSA level and digital rectal examination at 6-month intervals. Transrectal ultrasound-guided prostate biopsies were performed during the first year of follow-up, and every 2 or 3 years thereafter. The pathology details of biopsies were analyzed and compared with the current series on AS.

RESULTS

Three-hundred nineteen patients undergoing AS were evaluated with a median follow-up of 5.3 years and a mean age of 67.4 years. Sixty-three patients did not meet all the criteria to be considered low-risk PC but were included in the analysis. Overall, 128 patients (40.1%) underwent active treatment (84.7% of them due to pathological progression in surveillance biopsies). The proportion of patients with a reported upgrading ranged between 19.4% and 35.3%, although only the fourth biopsy showed an upgrading proportion of over 30%. Limitations include the retrospective design of the study and the existence of different protocols between other cohorts that make it difficult to compare their results.

CONCLUSIONS

For patients who remained in surveillance the percentage of upgrading increased slightly with the time, being more frequent after the third-surveillance biopsy. These findings support the importance of extending surveillance biopsies for patients who remain candidates for curative treatment.

Determining Clinically Based Factors Associated With Reclassification in the Pre-MRI Era using a Large Prospective Active Surveillance Cohort

OBJECTIVE

To report biopsy-related and oncologic outcomes in a large prospective active surveillance cohort that was initiated in the premagnetic resonance imaging era and to additionally identify clinical factors associated with disease reclassification in order to inform future studies designed to improve enrollment and follow-up on active surveillance.

METHODS

Patients were prospectively enrolled at a single institution from 2006 to 2014 and followed until 2016. Men with Gleason 6 or 7 disease were eligible, and those with >6 months follow-up were included in the analysis. Patients were risk stratified based on clinical/pathologic criteria, including based on a combination of baseline and confirmatory biopsy tumor characteristics. Reclassification-free survival, based on tumor volume increase or Gleason score increase, was analyzed using multivariable Cox proportional hazards models.

RESULTS

Of 825 enrolled patients, 682 met inclusion criteria. Median follow-up was 40 months (range 6.6-126.8). Disease was reclassified in 249 (36.5%), and 157 (23.0%) underwent treatment. A single positive core with a negative confirmatory biopsy was significantly associated with time to reclassification (median not met vs 43 months, log rank test P <.001). Composite tumor length, defined as the combined tumor length between baseline and confirmatory biopsies, was associated with shorter Gleason upgrade-free survival (hazard ratio 1.24, 95% confidence interval 1.11-1.40, P <.001) in multivariable analysis.

CONCLUSION

Baseline stratification using clinical factors including tumor length may refine risk stratification and offer the foundation on which new systems that incorporate modalities such as magnetic resonance imaging may be based.

Active surveillance outcomes in prostate cancer patients: the use of transperineal template-guided mapping biopsy for patient selection

PURPOSE

To evaluate active surveillance (AS) outcomes including overall survival (OS), freedom from distant metastases (FDM), freedom from therapeutic intervention (FTI), and quality of life (QOL) outcomes in prostate cancer patients using transperineal template-guided mapping biopsy (TTMB) for patient selection.

METHODS

From April 2005-January 2016, 226 consecutive, prospectively evaluated prostate cancer patients underwent TTMB for either low-grade prostate cancer or persistently elevated prostate-specific antigen (PSA) and/or the presence of ASAP. Evaluated outcomes included OS, FDM, FTI and QOL including urinary, bowel, sexual function and depression. Repeat biopsy was based on PSA kinetics and/or abnormal digital rectal examination.

RESULTS

Of the 226 patients, 212 (93.8%) were Gleason 3 + 3 and 14 (6.2%) were Gleason 3 + 4. The median follow-up was 5.0 years (range 0.8-13.0 years). The mean prostate volume was 61.3 cm³ with a mean of 59.5 TTMB cores/patient. At the time of AS enrollment, an average of 72.9 cores (TRUS + TTMB) had been obtained for each patient. At 8 years, OS, FTI and FDM were 92.5, 96.8 and 100%. Two hundred and twenty-two patients (98.2%) had a PSA doubling time of more than 3 years. No statistical changes in urinary function, bowel function or depression were noted. At 8 years, 73% of the patients maintained erectile function.

CONCLUSION

Within the confines of the follow-up of this study, the use of TTMB for patient selection identifies a cohort of patients unlikely to develop biochemical or clinical progression and maintain a favorable quality of life.

Does the introduction of prostate multiparametric magnetic resonance imaging into the active surveillance protocol for localized prostate cancer improve patient re-classification?

OBJECTIVES

To determine whether replacement of protocol-driven repeat prostate biopsy (PB) with multiparametric magnetic resonance imaging (mpMRI) ± repeat targeted prostate biopsy (TB) when evaluating men on active surveillance (AS) for low-volume, low- to intermediate-risk prostate cancer (PCa) altered the likelihood of or time to treatment, or reduced the number of repeat biopsies required to trigger treatment.

PATIENTS AND METHODS

A total of 445 patients underwent AS in the period 2010-2016 at our institution, with a median (interquartile range [IQR]) follow-up of 2.4 (1.2-3.7) years. Up to 2014, patients followed a 'pre-2014' AS protocol, which incorporated PB, and subsequently, according to the 2014 National Institute for Health and Care Excellence (NICE) guidelines, patients followed a '2014-present' AS protocol that included mpMRI. We identified four groups of patients within the cohort: 'no mpMRI and no PB'; 'PB alone'; 'mpMRI ± TB'; and 'PB and mpMRI ± TB'. Kaplan-Meier plots and log-rank tests were used to compare groups.

RESULTS

Of 445 patients, 132 (30%) discontinued AS and underwent treatment intervention, with a median (IQR) time to treatment of 1.55 (0.71-2.4) years. The commonest trigger for treatment was PCa upgrading after mpMRI and TB (43/132 patients, 29%). No significant difference was observed in the time at which patients receiving a PB alone or receiving mpMRI ± TB discontinued AS to undergo treatment (median 1.9 vs 1.33 years; P = 0.747). Considering only those patients who underwent repeat biopsy, a greater proportion of patients receiving TB after mpMRI discontinued AS compared with those receiving PB alone (29/66 [44%] vs 32/87 [37%]; P = 0.003). On average, a single set of repeat biopsies was needed to trigger treatment regardless of whether this was a PB or TB.

CONCLUSIONS

Replacing a systematic PB with mpMRI ±TB as part of an AS protocol increased the likelihood of re-classifying patients on AS and identifying men with clinically significant disease requiring treatment. mpMRI ±TB as part of AS thereby represents a significant advance in the oncological safety of the AS protocol.

Multiparametric Magnetic Resonance Imaging for Active Surveillance of Prostate Cancer

Active surveillance has gained popularity as an acceptable management option for men with low-risk prostate cancer. Successful utilization of this strategy can delay or prevent unnecessary interventions - thereby reducing morbidity associated with overtreatment. The usefulness of active surveillance primarily depends on correct identification of patients with low-risk disease. However, current population-wide algorithms and tools do not adequately exclude high-risk disease, thereby limiting the confidence of clinicians and patients to go on active surveillance. Novel imaging tools such as mpMRI provide information about the size and location of potential cancers enabling more informed treatment decisions. The term “multiparametric” in prostate mpMRI refers to the summation of several MRI series into one examination whose initial goal is to identify potential clinically-significant lesions suitable for targeted biopsy. The main advantages of MRI are its superior anatomic resolution and the lack of ionizing radiation. Recently, the Prostate Imaging-Reporting and Data System has been instituted as an international standard for unifying mpMRI results. The imaging sequences in mpMRI defined by Prostate Imaging Reporting and Data System version 2 includes: T2-weighted MRI, diffusion-weighted MRI, derived apparent-diffusion coefficient from diffusion-weighted MRI, and dynamic contrast-enhanced MRI. The use of mpMRI prior to starting active surveillance could prevent those with missed, high-grade lesions from going on active surveillance, and reassure those with minimal disease who may be hesitant to take part in active surveillance. Although larger validation studies are still necessary, preliminary results suggest mpMRI has a role in selecting patients for active surveillance. Less certain is the role of mpMRI in monitoring patients on active surveillance, as data on this will take a long time to mature. The biggest obstacles to routine use of prostate MRI are quality control, cost, reproducibility, and access. Nevertheless, there is great a potential for mpMRI to improve outcomes and quality of treatment. The major roles of MRI will continue to expand and its emerging use in standard of care approaches becomes more clearly defined and supported by increasing levels of data.

Randomized Trial of Partial Gland Ablation with Vascular Targeted Phototherapy versus Active Surveillance for Low Risk Prostate Cancer: Extended Followup and Analyses of Effectiveness

PURPOSE

The prospective PCM301 trial randomized 413 men with low risk prostate cancer to partial gland ablation with vascular targeted photodynamic therapy in 207 and active surveillance in 206. Two-year outcomes were reported previously. We report 4-year rates of intervention with radical therapy and further assess efficacy with biopsy results.

MATERIALS AND METHODS

Prostate biopsies were mandated at 12 and 24 months. Thereafter patients were monitored for radical therapy with periodic biopsies performed according to the standard of care at each institution. Ablation efficacy was assessed by biopsy results overall and in field in the treated lobe or the lobe with index cancer.

RESULTS

Conversion to radical therapy was less likely in the ablation cohort than in the surveillance cohort, including 7% vs 32% at 2 years, 15% vs 44% at 3 years and 24% vs 53% at 4 years (HR 0.31, 95% CI 0.21-0.46). Radical therapy triggers were similar in the 2 arms. Cancer progression rates overall and by grade were significantly lower in the ablation cohort (HR 0.42, 95% CI 0.29-0.59). End of study biopsy results were negative throughout the prostate in 50% of patients after ablation vs 14% after surveillance (risk difference 36%, 95% CI 28-44). Gleason 7 or higher cancer was less likely for ablation than for surveillance (16% vs 41%). Of the in field biopsies 10% contained Gleason 7 cancer after ablation vs 34% after surveillance.

CONCLUSIONS

In this randomized trial of partial ablation of low risk prostate cancer photodynamic therapy significantly reduced the subsequent finding of higher grade cancer on biopsy. Consequently fewer cases were converted to radical therapy, a clinically meaningful benefit that lowered treatment related morbidity.

Italian cultural adaptation of the Memorial Anxiety for Prostate Cancer scale for the population of men on active surveillance

Purpose:

The Memorial Anxiety Scale for Prostate Cancer (MAX-PC) is a self-report questionnaire that was developed in English to assess prostate cancer (PCa)-related anxiety. The aim of this study was to perform a cultural adaptation for the tool to be used in a population of Italian men on active surveillance (AS).

Methods:

A total of 222 patients with localized PCa who were recruited for the Prostate Cancer Research International: Active Surveillance (PRIAS) protocol completed the MAX-PC. Psychometric analysis was performed to assess reliability indexes. A Spearman rank correlation was used to test the association between MAX-PC scales and other questionnaires and was used for longitudinal analysis.

Results:

Cronbach coefficients and item to total correlation demonstrated good internal consistency. Some items related to the repetition of the PSA test showed a large floor effect and thus were poorly effective in measuring anxiety for PSA testing in patients on AS. Confirmatory factor analysis partly failed to reproduce the structure of the original version. A modified version of MAX-PC, excluding the items with a large floor effect, was thus considered for AS patients. Factor analysis on this version demonstrated considerable consistency with the presence of 3 subscales: anxiety related to PCa, anxiety related to PSA testing, and anxiety related to the fear of tumor progression. Longitudinal analysis showed an acceptable validity over time. The MAX-PC was correlated with the anxious preoccupation subscale of the Mini-Mental Adjustment to Cancer scale.

Conclusions:

A slightly modified version of the MAX-PC was developed for use in Italian men on AS. This instrument appears to be a valid and reliable tool that measures anxiety in men with PCa who are enrolled in AS programs.

Comparative Analysis of Biopsy Upgrading in Four Prostate Cancer Active Surveillance Cohorts

BACKGROUND

Active surveillance (AS) is increasingly accepted for managing low-risk prostate cancer, yet there is no consensus about implementation. This lack of consensus is due in part to uncertainty about risks for disease progression, which have not been systematically compared or integrated across AS studies with variable surveillance protocols and dropout to active treatment.

OBJECTIVE

To compare risks for upgrading from a Gleason score (GS) of 6 or less to 7 or more across AS studies after accounting for differences in surveillance intervals and competing treatments and to evaluate tradeoffs of more versus less frequent biopsies.

DESIGN

Joint statistical model of longitudinal prostate-specific antigen (PSA) levels and risks for biopsy upgrading.

SETTING

Johns Hopkins University (JHU); Canary Prostate Active Surveillance Study (PASS); University of California, San Francisco (UCSF); and University of Toronto (UT) AS studies.

PATIENTS

2576 men aged 40 to 80 years with a GS between 2 and 6 and clinical stage T1 or T2 prostate cancer enrolled between 1995 and 2014.

MEASUREMENTS

PSA levels and biopsy GSs.

RESULTS

After variable surveillance intervals and competing treatments were accounted for, estimated risks for biopsy upgrading were similar in the PASS and UT studies but higher in UCSF and lower in JHU studies. All cohorts had a delay of 3 to 5 months in detecting upgrading with biennial biopsies starting after a first confirmatory biopsy versus annual biopsies.

LIMITATION

The model does not account for possible misclassification of biopsy GS.

CONCLUSION

Men in different AS studies have different risks for biopsy upgrading after variable surveillance protocols and competing treatments are accounted for. Despite these differences, the consequences of more versus less frequent biopsies seem to be similar across cohorts. Biennial biopsies seem to be an acceptable alternative to annual biopsies.

PRIMARY FUNDING SOURCE

National Cancer Institute.

Active Surveillance Versus Watchful Waiting for Localized Prostate Cancer: A Model to Inform Decisions

BACKGROUND

An increasing proportion of prostate cancer is being managed conservatively. However, there are no randomized trials or consensus regarding the optimal follow-up strategy.

OBJECTIVE

To compare life expectancy and quality of life between watchful waiting (WW) versus different strategies of active surveillance (AS).

DESIGN, SETTING, AND PARTICIPANTS

A Markov model was created for US men starting at age 50, diagnosed with localized prostate cancer who chose conservative management by WW or AS using different testing protocols (prostate-specific antigen every 3-6 mo, biopsy every 1-5 yr, or magnetic resonance imaging based). Transition probabilities and utilities were obtained from the literature.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Primary outcomes were life years and quality-adjusted life years (QALYs). Secondary outcomes include radical treatment, metastasis, and prostate cancer death.

RESULTS AND LIMITATIONS

All AS strategies yielded more life years compared with WW. Lifetime risks of prostate cancer death and metastasis were, respectively, 5.42% and 6.40% with AS versus 8.72% and 10.30% with WW. AS yielded more QALYs than WW except in cohorts age >65 yr at diagnosis, or when treatment-related complications were long term. The preferred follow-up strategy was also sensitive to whether people value short-term over long-term benefits (time preference). Depending on the AS protocol, 30-41% underwent radical treatment within 10 yr. Extending the surveillance biopsy interval from 1 to 5 yr reduced life years slightly, with a 0.26 difference in QALYs.

CONCLUSIONS

AS extends life more than WW, particularly for men with higher-risk features, but this is partly offset by the decrement in quality of life since many men eventually receive treatment.

PATIENT SUMMARY

More intensive active surveillance protocols extend life more than watchful waiting, but this is partly offset by decrements in quality of life from subsequent treatment.

Qualitative study on decision-making by prostate cancer physicians during active surveillance

OBJECTIVE

To explore and identify factors that influence physicians' decisions while monitoring patients with prostate cancer on active surveillance (AS).

SUBJECTS AND METHODS

A purposive sampling strategy was used to identify physicians treating prostate cancer from diverse clinical backgrounds and geographic areas across the USA. We conducted 24 in-depth interviews from July to December 2015, until thematic saturation was reached. The Applied Thematic Analysis framework was used to guide data collection and analysis. Interview transcripts were reviewed and coded independently by two researchers. Matrix analysis and NVivo software were used for organization and further analysis.

RESULTS

Eight key themes emerged to explain variation in AS monitoring: (i) physician comfort with AS; (ii) protocol selection; (iii) beliefs about the utility and quality of testing; (iv) years of experience and exposure to AS during training; (v) concerns about inflicting 'harm'; (vi) patient characteristics; (vii) patient preferences; and (viii) financial incentives.

CONCLUSION

These qualitative data reveal which factors influence physicians who manage patients on AS. There is tension between providing standardized care while also considering individual patients' needs and health status. Additional education on AS is needed during urology training and continuing medical education. Future research is needed to empirically understand whether any specific protocol is superior to tailored, individualized care.

Prediction of the Pathologic Gleason Score to Inform a Personalized Management Program for Prostate Cancer

BACKGROUND

Active surveillance (AS) is an alternative to curative intervention, but overtreatment persists. Imperfect alignment of prostate biopsy and Gleason score after radical prostatectomy (RP) may be a contributing factor.

OBJECTIVE

To develop a statistical model that predicts the post-RP Gleason score (pathologic Gleason score [PGS]) using clinical observations made in the course of AS.

DESIGN, SETTING, AND PARTICIPANTS

Repeated prostate-specific antigen measurements and biopsy Gleason scores from 964 very low-risk patients in the Johns Hopkins Active Surveillance cohort were used in the analysis. PGS observations from 191 patients who underwent RP were also included.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

A Bayesian joint model based on accumulated clinical data was used to predict PGS in these categories: 6 (grade group 1), 3+4 (grade group 2), 4+3 (grade group 3), and 8-10 (grade groups 4 and 5). The area under the receiver operating characteristic curve (AUC) and calibration of predictions was assessed in patients with post-RP Gleason score observations.

RESULTS AND LIMITATIONS

The estimated probability of harboring a PGS >6 was <20% for most patients who had not experienced grade reclassification or elected surgery. Among patients with post-RP Gleason score observations, the AUC for predictions of PGS >6 was 0.74 (95% confidence interval, 0.66-0.81), and the mean absolute error was 0.022.

CONCLUSIONS

Although the model requires external validation prior to adoption, PGS predictions can be used in AS to inform decisions regarding follow-up biopsies and remaining on AS. Predictions can be updated as additional data are observed. The joint modeling framework also accommodates novel biomarkers as they are identified and measured on AS patients.

PATIENT SUMMARY

Measurements taken in the course of active surveillance can be used to accurately predict patients' underlying prostate cancer status. Predictions can be communicated to patients via a decision support tool and used to guide clinical decision making and reduce patient anxiety.

Outcomes of Active Surveillance after Initial Surveillance Prostate Biopsy

PURPOSE

We analyzed the rates of disease reclassification at initial and subsequent surveillance prostate biopsy as well as the treatment outcomes of deferred therapy among men on active surveillance for prostate cancer.

MATERIALS AND METHODS

From a prospective database we identified 300 men on active surveillance who had undergone initial surveillance prostate biopsy, with or without confirmatory biopsy, within 1 year of diagnosis. Of these men 261 (87%) were classified as having NCCN very low or low risk disease at diagnosis. Disease reclassification on active surveillance was defined as the presence of 50% or more positive cores and/or surveillance prostate biopsy Gleason score upgrading. Patients with type I disease reclassification included those with any surveillance prostate biopsy Gleason score upgrading, while patients with type II reclassification had to have primary Gleason pattern 4-5 disease on surveillance prostate biopsy. Outcomes after initial surveillance prostate biopsy were evaluated using actuarial analyses.

RESULTS

At the time of initial surveillance prostate biopsy 49 (16%) and 19 (6%) patients had type I and type II disease reclassification, respectively. Those who underwent confirmatory biopsy had significantly reduced rates of type I (9% vs 23%, p=0.001) and type II (3% vs 9%, p=0.01) reclassification at initial surveillance prostate biopsy. For the 251 patients without disease reclassification at initial surveillance prostate biopsy the 2-year rates of subsequent type I and II reclassification were 17% (95% CI 0-24) and 3% (95% CI 0.1-7), respectively. For the 93 patients who received deferred therapy the 5-year biochemical progression-free probability was 89% (95% CI 79-98), including 95%, 82% and 70% among those without, and those with type I and type II disease reclassification, respectively.

CONCLUSIONS

Patients on active surveillance with stable disease at the time of initial surveillance prostate biopsy may be appropriate candidates for less intensive surveillance prostate biopsy schedules.

Active surveillance for prostate cancer: current evidence and contemporary state of practice

Prostate cancer remains one of the most commonly diagnosed malignancies worldwide. Early diagnosis and curative treatment seem to improve survival in men with unfavourable-risk cancers, but significant concerns exist regarding the overdiagnosis and overtreatment of men with lower-risk cancers. To this end, active surveillance (AS) has emerged as a primary management strategy in men with favourable-risk disease, and contemporary data suggest that use of AS has increased worldwide. Although published surveillance cohorts differ by protocol, reported rates of metastatic disease and prostate-cancer-specific mortality are exceedingly low in the intermediate term (5-10 years). Such outcomes seem to be closely associated with programme-specific criteria for selection, monitoring, and intervention, suggesting that AS--like other management strategies--could be individualized based on the level of risk acceptable to patients in light of their personal preferences. Additional data are needed to better establish the risks associated with AS and to identify patient-specific characteristics that could modify prognosis.

Comorbid Disease Burden is Independently Associated with Higher Risk Disease at Prostatectomy in Patients Eligible for Active Surveillance

PURPOSE

Comorbid medical conditions are highly prevalent among patients with prostate cancer and may be associated with more aggressive disease. We investigated the association between comorbidity burden and higher risk disease among men eligible for active surveillance.

MATERIALS AND METHODS

Using the National Cancer Data Base we identified 29,447 cases of low risk (Gleason score 6 or less, cT1/T2a, prostate specific antigen less than 10 ng/ml) prostate cancer managed with prostatectomy from 2010 to 2011. The primary outcome was pathological upgrading (Gleason score greater than 6) or up staging (T3-T4/N1). The association between Charlson score and upgrading/up staging was analyzed using multivariate logistic regression.

RESULTS

The study sample comprised 29,447 men, of which 449 (1.5%) had Charlson scores greater than 1. At prostatectomy 44% of cases were upgraded/up staged. On multivariate analysis Charlson score greater than 1, age 70 years or greater, nonwhite race, higher prostate specific antigen and higher percentage of cores involved with disease were significantly associated with upgrading/up staging. After further adjusting for age, race, prostate specific antigen and core involvement, Charlson score remained a significant predictor of upgrading/up staging for younger white men. Specifically, white men less than 70 years old with Charlson comorbidity index greater than 1 had 1.3-fold higher odds of upgrading/up staging than men with Charlson comorbidity index 1 or less (OR 1.31, 95% CI 1.03-1.67, p=0.029).

CONCLUSIONS

Comorbidity burden is strongly and independently associated with pathological upgrading/up staging in men with clinically low risk prostate cancer. This finding may help improve disease risk assessment and clinical decision making in men with comorbidities considering active surveillance.

Validation of active surveillance criteria for pathologically insignificant prostate cancer in Asian men

OBJECTIVES

To validate the ability of contemporary active surveillance protocols to predict pathologically insignificant prostate cancer among Asian men undergoing radical prostatectomy.

METHODS

We retrospectively reviewed data on 132 patients eligible for any active surveillance criteria out of 450 patients that underwent radical prostatectomy at several institutions between 2006 and 2013. We validated the ability of seven contemporary active surveillance protocols to predict pathologically insignificant prostate cancer. Traditional and updated criteria to define pathologically insignificant prostate cancer were used. Predictive factors for pathologically insignificant prostate cancer were determined by logistic regression analysis.

RESULTS

The predictive rate for updated pathologically insignificant prostate cancer of respective active surveillance criteria was 51% for Johns Hopkins Medical Institution, 41% for Prostate Cancer Research International: Active Surveillance Study, 39% for University of Miami, 32% for University of California, San Francisco, 32% for Memorial Sloan-Kettering Cancer Center, 31% for Kakehi and 27% for University of Toronto. Predictive rates for pathologically insignificant prostate cancer in Asian men were far lower than in USA men. On multivariate analysis, predictive factors of updated pathologically insignificant cancer was prostate volume (odds ratio 1.07, P = 0.004). By adding prostate volume to Prostate Cancer Research International: Active Surveillance Study criteria, the predictive rate for updated insignificant prostate cancer was improved up to 66.7%.

CONCLUSIONS

Active surveillance can be carried out considering the clinical characteristics of prostate cancers depending on ethnicity, as current active surveillance criteria seem to have a lower predictive ability value of insignificant prostate cancer in Asian men compared with men in Western countries.