The Effect of Race/Ethnicity on the Accuracy of the 2001 Partin Tables for Predicting Pathologic Stage of Localized Prostate Cancer

Influence of African American race on the association between preoperative biopsy grade group and adverse histopathologic features of radical prostatectomy

BACKGROUND

The current study was performed to evaluate the influence of race on the association between biopsy grade group (GrGp) and the risk of detectable prostate-specific antigen (PSA) and adverse histopathological outcomes after radical prostatectomy (RP).

METHODS

Data regarding 4073 men (1344 African American men; 33%) who were treated with RP were categorized based on the 5-tiered GrGp system. Logistic regression was used to test the association between biopsy GrGp and PSA nadir (<0.1 ng/mL) after RP as well as adverse pathological features among all patients and stratified by race.

RESULTS

Those patients with a higher biopsy GrGp were found to have lower odds of achieving a PSA nadir <0.1 ng/mL after RP on unadjusted and multivariable analysis (both P < .001). On unadjusted and multivariable analysis, higher GrGp was associated with increased odds of each of the adverse pathological features, namely, GrGp ≥3, extraprostatic extension, seminal vesicle invasion, positive surgical resection margin, and positive lymph nodes (all P < .001). Race had no significant interaction with biopsy GrGp in the prediction of PSA nadir after RP (P = .91) or any adverse pathological features (all P > .06) except positive lymph nodes. When the models were stratified by race, the associations between preoperative biopsy GrGp and having a PSA nadir <0.1 ng/mL, high-grade final pathology, or other adverse histopathologic features were similar in both races except as noted for positive lymph nodes.

CONCLUSIONS

Higher preoperative biopsy GrGp is associated with increased odds of adverse histopathological findings as well as lower odds of a PSA nadir <0.1 ng/mL after RP. These associations are largely independent of race, suggesting that GrGp is an accurate tool for risk stratification in both black and white men.

Population-Based External Validation of the Updated 2012 Partin Tables in Contemporary North American Prostate Cancer Patients

OBJECTIVE

To externally validate the updated 2012 Partin Tables in contemporary North American patients treated with radical prostatectomy (RP) for localized prostate cancer (PCa) at community institutions.

MATERIALS AND METHODS

We examined records of 25,254 patients treated with RP and pelvic lymph node dissection (PLND) between 2010 and 2013, within the surveillance, epidemiology, and end results database. The ROC derived AUC assessed discriminant properties of the updated 2012 Partin Tables of organ confined disease (OC), extracapsular extension (ECE), seminal vesical invasion (SVI), and lymph node invasion (LNI). Calibration plots focused on calibration between predicted and observed rates.

RESULTS

Proportions of OC, ECE, SVI, and LNI at RP were 69.8%, 18.4%, 7.4%, and 4.4%, respectively. Accuracy for prediction of OC, ECE, SVI, and LNI was 70.4%, 59.9%, 72.9%, and 77.1%, respectively. In subgroup analyses in patients with nodal yield >10, accuracy for LNI prediction was 76.0%. Subgroup analyses in elderly patients and in African American patients revealed decreased accuracy for prediction of all four endpoints. Last but not least, SVI and LNI calibration plots showed excellent agreement, versus good agreement for OC (maximum underestimation of 10%) and poor agreement for ECE (maximum overestimation of 12%).

CONCLUSION

Taken together, the updated 2012 Partin Tables can be unequivocally endorsed for prediction of OC, SVI, and LNI in community-based patients with localized PCa. Conversely, ECE predictions failed to reach the minimum accuracy requirements of 70%. Prostate 77:105-113, 2017. © 2016 Wiley Periodicals, Inc.

Genetic and molecular differences in prostate carcinogenesis between African American and Caucasian American men

Prostate cancer is the most common non-skin cancer and the second leading cause of cancer-related death for men in the United States. Prostate cancer incidence and associated mortality are highest in African American men in comparison to other races. The observed differences in incidence and disease aggressiveness at presentation support a potential role for different pathways of prostate carcinogenesis between African American and Caucasian men. This review focuses on some of the recent molecular biology discoveries, which have been investigated in prostate carcinogenesis and their likely contribution to the known discrepancies across race and ethnicity. Key discussion points include the androgen receptor gene structure and function, genome-wide association studies and epigenetics. The new observations of the ethnic differences of the ERG oncogene, the most common prostate cancer gene, are providing new insights into ERG based stratification of prostate cancers in the context of ethnically diverse patient populations. This rapidly advancing knowledge has the likely potential to benefit clinical practice. Current and future work will improve the ability to sub-type prostate cancers by molecular alterations and lead to targeted therapy against this common malignancy.

Is primary prostate cancer treatment influenced by likelihood of extraprostatic disease? A surveillance, epidemiology and end results patterns of care study

PURPOSE

To examine the patterns of primary treatment in a recent population-based cohort of prostate cancer patients, stratified by the likelihood of extraprostatic cancer as predicted by disease characteristics available at diagnosis.

METHODS AND MATERIALS

A total of 157,371 patients diagnosed from 2004 to 2008 with clinically localized and potentially curable (node-negative, nonmetastatic) prostate cancer, who have complete information on prostate-specific antigen, Gleason score, and clinical stage, were included. Patients with clinical T1/T2 disease were grouped into categories of <25%, 25%-50%, and >50% likelihood of having extraprostatic disease using the Partin nomogram. Clinical T3/T4 patients were examined separately as the highest-risk group. Logistic regression was used to examine the association between patient group and receipt of each primary treatment, adjusting for age, race, year of diagnosis, marital status, Surveillance, Epidemiology and End Results database region, and county-level education. Separate models were constructed for primary surgery, external-beam radiotherapy (RT), and conservative management.

RESULTS

On multivariable analysis, increasing likelihood of extraprostatic disease was significantly associated with increasing use of RT and decreased conservative management. Use of surgery also increased. Patients with >50% likelihood of extraprostatic cancer had almost twice the odds of receiving prostatectomy as those with <25% likelihood, and T3-T4 patients had 18% higher odds. Prostatectomy use increased in recent years. Patients aged 76-80 years were likely to be managed conservatively, even those with a >50% likelihood of extraprostatic cancer (34%) and clinical T3-T4 disease (24%). The proportion of patients who received prostatectomy or conservative management was approximately 50% or slightly higher in all groups.

CONCLUSIONS

There may be underutilization of RT in older prostate cancer patients and those with likely extraprostatic disease. Because more than half of prostate cancer patients do not consult with a radiation oncologist, a multidisciplinary consultation may affect the treatment decision-making process.

Racial/Ethnic patterns in prostate cancer outcomes in an active surveillance cohort

Introduction. Concern regarding overtreatment of prostate cancer (CaP) is leading to increased attention on active surveillance (AS). This study examined CaP survivors on AS and compared secondary treatment patterns and overall survival by race/ethnicity. Methods. The study population consisted of CaP patients self-classified as black or white followed on AS in the Center for Prostate Disease Research (CPDR) multicenter national database between 1989 and 2008. Secondary treatment included radical prostatectomy (RP), external beam radiation therapy or brachytherapy (EBRT-Br), and hormone therapy (HT). Secondary treatment patterns and overall survival were compared by race/ethnicity. Results. Among 886 eligible patients, 21% were black. Despite racial differences in risk characteristics and secondary treatment patterns, overall survival was comparable across race. RP following AS was associated with the longest overall survival. Conclusion. Racial disparity in overall survival was not observed in this military health care beneficiary cohort with an equal access to health care.

Prediction of patient-specific risk and percentile cohort risk of pathological stage outcome using continuous prostate-specific antigen measurement, clinical stage and biopsy Gleason score

OBJECTIVES

• To develop a '2010 Partin Nomogram' with total prostate-specific antigen (tPSA) as a continuous biomarker, in light of the fact that the current 2007 Partin Tables restrict the application of tPSA as a non-continuous biomarker by creating 'groups' for risk stratification with tPSA levels (ng/mL) of 0-2.5, 2.6-4.0, 4.1-6.0, 6.1-10.0 and >10.0. • To use a 'predictiveness curve' to calculate the percentile risk of a patient among the cohort.

PATIENTS AND METHODS

• In all, 5730 and 1646 patients were treated with radical prostatectomy (without neoadjuvant therapy) between 2000 and 2005 at the Johns Hopkins Hospital (JHH) and University Clinic Hamburg-Eppendorf (UCHE), respectively. • Multinomial logistic regression analysis was performed to create a model for predicting the risk of the four non-ordered pathological stages, i.e. organ-confined disease (OC), extraprostatic extension (EPE), and seminal vesicle (SV+) and lymph node (LN+) involvement. • Patient-specific risk was modelled as a function of the B-spline basis of tPSA (with knots at the first, second and third quartiles), clinical stage (T1c, T2a, and T2b/T2c) and biopsy Gleason score (5-6, 3 + 4 = 7, 4 + 3 = 7, 8-10).

RESULTS

• The '2010 Partin Nomogram' calculates patient-specific absolute risk for all four pathological outcomes (OC, EPE, SV+, LN+) given a patient's preoperative clinical stage, tPSA and biopsy Gleason score. • While having similar performance in terms of calibration and discriminatory power, this new model provides a more accurate prediction of patients' pathological stage than the 2007 Partin Tables model. • The use of 'predictiveness curves' has also made it possible to obtain the percentile risk of a patient among the cohort and to gauge the impact of risk thresholds for making decisions regarding radical prostatectomy.

CONCLUSION

• The '2010 Partin Nomogram' using tPSA as a continuous biomarker together with the corresponding 'predictiveness curve' will help clinicians and patients to make improved treatment decisions.

Validation of the partin nomogram for prostate cancer in a national sample

PURPOSE

The Partin tables are a nomogram that is widely used to discriminate prostate cancer pathological stages, given common preoperative clinical characteristics. The nomogram is based on patients undergoing radical prostatectomy at The Johns Hopkins Medical Institutions. We validated the Partin tables in a large, population based sample.

MATERIALS AND METHODS

The National Cancer Institute Surveillance, Epidemiology and End Results database was used to identify patients treated from 2004 to 2005 who underwent radical prostatectomy. The 2007 Partin tables were used to estimate the prevalence of positive lymph nodes, seminal vesicle invasion, extraprostatic extension and organ confined disease in men with prostate cancer in the database using clinical stage, preoperative prostate specific antigen and Gleason score. The discriminative ability of the tables was explored by constructing ROC curves.

RESULTS

We identified 11,185 men who underwent radical prostatectomy for prostate cancer in 2004 to 2005. The Partin tables discriminated well between patient groups at risk for positive lymph nodes and seminal vesicle invasion (AUC 0.77 and 0.74, respectively). The discrimination of extraprostatic extension and organ confined disease was more limited (AUC 0.62 and 0.68, respectively). The AUC for positive lymph nodes was 0.78 in white men, 0.73 in black men and 0.83 in Asian/Pacific Islander men (p = 0.17). The AUC for positive lymph nodes in men 61 years old or younger was 0.80 vs 0.74 in men older than 61 years (p = 0.03).

CONCLUSIONS

The Partin tables showed excellent discrimination for seminal vesicle invasion and positive lymph nodes. Discrimination of extraprostatic extension and organ confined disease was more limited. The Partin tables performed best in young men.

The effect of race on the discriminatory accuracy of models to predict biochemical recurrence after radical prostatectomy: results from the Shared Equal Access Regional Cancer Hospital and Duke Prostate Center databases

To evaluate whether race modifies the accuracy of nomograms to predict biochemical recurrence (BCR) after radical prostatectomy among subjects from the Shared Equal Access Regional Cancer Hospital (SEARCH) and Duke Prostate Center (DPC) databases. Retrospective analysis of 1721 and 4511 subjects from the SEARCH and DPC cohorts, respectively. The discrimination accuracy for BCR of seven previously published predictive models was assessed using concordance index and compared between African-American men (AAM) and Caucasian men (CM). AAM represented 44% of SEARCH and 14% of DPC. In both cohorts, AAM were more likely to experience BCR than CM (P<0.01). In SEARCH, the mean concordance index across all seven models was lower in AAM (0.678) than CM (0.715), though the mean difference between CM and AAM was modest (0.037; range 0.015-0.062). In DPC the overall mean concordance index for BCR across all seven nomograms was 0.686. In contrast to SEARCH, the mean concordance index in DPC was higher in AAM (0.717) than CM (0.681), though the mean differences between CM and AAM was modest (-0.036; range -0.078 to -0.004). Across all seven models for predicting BCR, the discriminatory accuracy was better among CM in SEARCH and better among AAM in DPC. The mean difference in discriminatory accuracy of all seven nomograms between AAM and CM was approximately 3-4%. This indicates that currently used predictive models have similar performances among CM and AAM. Therefore, nomograms represent a valid and accurate method to predict BCR regardless of race.

Novel predictive tools for Irish radical prostatectomy pathological outcomes: development and validation

AIMS

We developed and validated prostate cancer predictive models for Irish patients, allowing individualised predictions of radical prostatectomy pathological outcomes.

METHODS

Retrospective review of the Irish Prostate Cancer Research Consortium database from 2003 to 2008 was performed. Two predictive models were formulated: a replica of the Partin tables (n = 169) and a look-up table based on PSA and biopsy Gleason Score (n = 253). Clinico-pathological parameters were compared to the Partin data set. Internal validation was performed.

RESULTS

In total, 70% of patients were at clinical stage T1c. 5.8% had a PSA less than 4.1 ng/ml, whereas 25% of the Partin patients had a PSA in this range. Maximal predictive accuracy was seen for seminal vesicle invasion (area under the curve = 72%). Prediction of extra-prostatic extension and lymph node involvement was only equivalent to that of a chance phenomenon.

CONCLUSIONS

Our current results do not support the introduction of the formulated predictive models into routine clinical practice.