Optimum Tools for Predicting Clinical Outcomes in Prostate Cancer Patients Undergoing Radical Prostatectomy: A Systematic Review of Prognostic Accuracy and Validity

External validation of the Memorial Sloan Kettering Cancer Center preoperative nomogram predicting lymph node invasion in a cohort of high-grade prostate cancer patients

BACKGROUND

Commonly used preoperative nomograms predicting clinical and pathological outcomes in prostate cancer (PCa) patients have not been yet validated in high-grade only PCa patients. Our objective is to perform an external validation of the Memorial Sloan Kettering Cancer Center (MSKCC) preoperative nomogram as a predictor of lymph node invasion (LNI) in a cohort of high-grade PCa patients.

METHODS

We included patients with high-grade PCa (Gleason ≥8) treated at our institution between 2011 and 2020 with radical prostatectomy and pelvic lymph node dissection without receiving neoadjuvant or adjuvant therapy. The area under the curve (AUC) of the receiver operator characteristic (ROC) was used to quantify the accuracy of the model to predict LNI. A calibration plot was used to evaluate the model's precision, and a decision curve analysis was computed to evaluate the net benefit associated with its use. This study was approved by our institution's ethics board.

RESULTS

A total of 242 patients with a median age of 66 (60-71) years were included. LNI was observed in 70 (29%) patients with a mean of 16 (median = 15; range = 2-42) resected nodes. The MSKCC nomogram discriminative accuracy, as evaluated by the AUC-ROC was 79.0% (CI: [0.727-0.853]).

CONCLUSION

The MSKCC preoperative nomogram is a good predictor of LNI and a useful tool associated with net clinical benefit in this patient population.

Cribriform pattern 4/intraductal carcinoma of the prostate and persistent prostate-specific antigen after radical prostatectomy

Objectives

The objective of this study is to identify the effect of cribriform pattern 4 carcinoma/intraductal carcinoma of the prostate (CC/IDCP) on persistent prostate-specific antigen (PSA) levels after robot-assisted radical prostatectomy (RARP) in patients with localized prostate cancer (PCa).

Patients and Methods

This retrospective study included 730 consecutive patients with localized PCa who underwent RARP at Mie University (n = 392) and Aichi Medical University (n = 338) between 2015 and 2021. Patients with clinically metastatic PCa (cN1 and cM1) and those who received neoadjuvant and/or adjuvant therapy before biochemical recurrence were excluded. We evaluated the effects of CC/IDCP on persistent PSA levels after RARP. Persistent PSA was defined as PSA level ≥0.2 ng/mL at 1 month postoperatively and consecutively thereafter. Using factors from logistic regression analysis, models were developed to predict persistent PSA levels.

Results

Approximately 6.3% (n = 46) of the patients had persistent PSA levels. Patients with biopsy CC/IDCP (bCC/IDCP) and pathological CC/IDCP (pCC/IDCP) based on RARP specimens were 11.6% (85/730) and 36.5% (267/730), respectively. Multivariate analysis of the prediction of persistent PSA levels using preoperative factors revealed that PSA density, percentage of positive cancer cores, biopsy grade group and bCC/IDCP were independent prognostic factors. Furthermore, multivariate analysis of the prediction of persistent PSA levels using postoperative factors, excluding pN1, revealed that pathological grade group, pCC/IDCP, seminal vesicle invasion and lymphovascular invasion were independent prognostic factors. In the receiver operating characteristic curve analysis for predicting persistent PSA after RARP, areas under the receiver operating characteristic curve for the model with preoperative factors, postoperative factors, including pN1, and postoperative factors, excluding pN1, were 0.827, 0.833 and 0.834, respectively.

Conclusions

bCC/IDCP predicted persistent PSA after RARP in the overall population, while pCC/IDCP predicted persistent PSA only when the pN1 population was excluded. This may be useful for predicting susceptible patients with worse outcomes.

Prognostic factors among patients with pathological Grade Group 5 prostate cancer based on robot-associated radical prostatectomy specimens from a large Japanese cohort (MSUG94)

PURPOSE

There are no definitive prognostic factors for patients with pathological Grade Group 5 (pGG 5) prostate cancer (PCa) undergoing robot-associated radical prostatectomy (RARP). This study aimed to explore the prognostic factors among patients with pGG 5 PCa in a large Japanese cohort (MSUG94).

METHODS

This retrospective, multi-institutional cohort study was conducted between 2012 and 2021 at ten centers in Japan and included 3195 patients. Patients with clinically metastatic PCa (cN1 or cM1) and those receiving neoadjuvant and/or adjuvant therapy were excluded. Finally, 217 patients with pGG5 PCa were analyzed.

RESULTS

The median follow-up period was 28.0 months. The 3- and 5-year biochemical recurrence-free survival (BCRFS) rates of the overall population were 66.1% and 57.7%, respectively. The optimal threshold value (47.2%) for the percentage of positive cancer cores (PPCC) with any GG by systematic biopsy was chosen based on receiver operating characteristic curve analysis. Univariate analysis revealed that the prostate-specific antigen level at diagnosis, pT, pN, positive surgical margins (PSMs), lymphovascular invasion, and PPCC were independent prognostic factors for BCRFS. A multivariate analysis revealed that PSMs and PPCC were independent prognostic factors for BCRFS. Using these two predictors, we stratified BCRFS, metastasis-free survival (MFS), and castration-resistant PCa-free survival (CRPC-FS) among patients with pGG 5 PCa.

CONCLUSION

The combination of PSMs and PPCC may be an important predictor of BCRFS, MFS, and CRPC-FS in patients with pGG 5 PCa undergoing RARP.

Genetic Profiling of African American Patients With Prostatic Adenocarcinoma Metastatic to the Lymph Nodes: A Pilot Study

CONTEXT.—

Genetic profiling data of prostatic adenocarcinoma are derived from predominantly White patients. In African Americans, prostatic adenocarcinoma has a poorer prognosis, raising the possibility of distinct genetic alterations.

OBJECTIVE.—

To investigate the genomic alterations of prostatic adenocarcinoma metastatic to regional lymph nodes in African American patients, with an emphasis on SPOP mutation.

DESIGN.—

We retrospectively reviewed African American patients with pN1 prostatic adenocarcinoma managed with radical prostatectomy and lymph node dissection. Comprehensive molecular profiling was performed, and androgen receptor signaling scores were calculated.

RESULTS.—

Nineteen patients were included. The most frequent genetic alteration was SPOP mutations (5 of 17; 29.4% [95% CI: 10.3-56.0]). While most alterations were associated with a high androgen receptor signaling score, mutant SPOP was exclusively associated with a low median and interquartile range (IQR) androgen receptor signaling score (0.788 [IQR 0.765-0.791] versus 0.835 [IQR 0.828-0.842], P = .003). In mutant SPOP, mRNA expression of SPOP inhibitor G3BP1 and SPOP substrates showed a significantly decreased expression of AR (33.40 [IQR 28.45-36.30] versus 59.53 [IQR 53.10-72.83], P = .01), TRIM24 (3.95 [IQR 3.28-5.03] versus 9.80 [IQR 7.39-11.70], P = .008), and NCOA3 (15.19 [IQR 10.59-15.93] versus 21.88 [IQR 18.41-28.33], P = .046).

CONCLUSIONS.—

African American patients with metastatic prostate adenocarcinoma might have a higher prevalence of mutant SPOP (30%), compared to ∼10% in unselected cohorts with lower expressions of SPOP substrates. In our study, in patients with mutant SPOP, the mutation was associated with decreased SPOP substrate expression and androgen receptor signaling, raising concern for suboptimal efficacy of androgen deprivation therapy in this subset of patients.

Establishment and Validation of a Novel Prediction Model for Early Natural Biochemical Recurrence After Radical Prostatectomy Based on Post-Operative PSA at Sixth Week

Objective

Based on post-operative PSA at 6th week (PSA_6w) after radical prostatectomy to establish an optimal model for predicting natural biochemical recurrence (BCR).

Methods

A total of 742 patients with post-operative PSA_6w from PC-follow database, between January 2003 and October 2022, were included. All the patients had not received any hormone therapy and radiotherapy before operation and BCR. Of these patients, 588 cases operated by one surgeon were enrolled for modelling and another 154 cases operated by other surgeons were for external validation. After screened by Cox regression, the post-operative PSA_6w, pathological stage, Gleason Grade and positive surgical margins were adopted for modelling. The R software was used to plot the nomogram of the prediction model for BCR. C-index and calibration curve were calculated to evaluate the new model. Finally, integrated discrimination improvement was adopted to evaluate the prediction performances of the new nomogram model and the classical Kattan nomogram.

Results

The C-index of the new model was 0.871 (95% CI: 0.830-0.912). The calibration curve of the new model demonstrated superior consistency between the predicted and actual value. The C-index of the external validation group was 0.850 (95% CI: 0.742-0.958), which demonstrated perfect universality. The integrated discrimination improvement showed a 12.61% improvement in prediction performance over that of the classical Kattan nomogram (P < 0.01). Based on the new nomogram, patients were divided to high and low BCR group with a 3 year BCR-free cutoff probability as 74.72%. Low-risk patients, accounting for 77.89% of the patients, have no need to follow up frequently with a false-negative rate only 5.24%, which will save medical resources to a large extent.

Conclusion

Post-operative PSA6w is a sensitive risk biomarker for early natural BCR. The new nomogram model could predict BCR probability with a higher accuracy and will further simplify the clinical follow-up strategies.

Effect of Clinical Parameters on Risk of Death from Cancer after Radical Prostatectomy in Men with Localized and Locally Advanced Prostate Cancer

Background: The study aimed to assess predictors and to identify patients at increased risk of prostate-cancer-specific mortality (CSM) after radical prostatectomy (RP). Methods: A total of 2421 men with localized and locally advanced PCa who underwent RP in 2001−2017 were included in the study. CSM predictors were assessed using multivariate competing risk analysis. Death from other causes was considered a competing event. Cumulative CSM and other-cause mortality (OCM) were calculated in various combinations of predictors. Results: During the median 8 years (interquartile range 4.4−11.7) follow-up, 56 (2.3%) of registered deaths were due to PCa. Cumulative 10 years CSM and OCM was 3.6% (95% CI 2.7−4.7) and 15.9% (95% CI 14.2−17.9), respectively. The strongest predictors of CSM were Grade Group 5 (GG5) (hazard ratio (HR) 19.9, p < 0.0001), lymph node invasion (HR 3.4, p = 0.001), stage pT3b-4 (HR 3.1, p = 0.009), and age (HR 1.1, p = 0.0007). In groups created regarding age, stage, and GG, cumulative 10 years CSM ranged from 0.4−84.9%, whereas OCM varied from 0−43.2%. Conclusions: CSM after RP is related to GGs, pathological stage, age, and combinations of these factors, whereas other-cause mortality is only associated with age. Created CSM and OCM plots can help clinicians identify patients with the most aggressive PCa who could benefit from more intensive or novel multimodal treatment strategies.

Association Between Multiparametric Magnetic Resonance Imaging of the Prostate and Oncological Outcomes after Primary Treatment for Prostate Cancer: A Systematic Review and Meta-analysis

CONTEXT

The diagnostic accuracy of multiparametric magnetic resonance imaging (mpMRI) for prostate cancer (PCa) diagnosis has been extensively explored. Little is known about the prognostic value of mpMRI suspicion scores and other quantitative mpMRI information.

OBJECTIVE

To systematically review the current literature assessing the relationship between pretreatment mpMRI and oncological outcomes after primary treatment for PCa to assess the role of mpMRI as a prognostic tool.

EVIDENCE ACQUISITION

A computerized bibliographic search of MEDLINE/PubMed, EMBASE, Scopus, and the Cochrane Library CENTRAL databases was performed for all studies assessing the relationship between mpMRI and oncological outcomes after primary treatment for PCa. The review protocol is registered in the PROSPERO database (CRD42020209899).

EVIDENCE SYNTHESIS

A total of six studies were included. Reliable evidence is still limited in this field. The Prostate Imaging-Reporting and Data System (PI-RADS) score was an independent predictor of biochemical recurrence (BCR) after radical prostatectomy (RP) in the majority of the studies included. The tumor volume at mpMRI was not significantly associated with BCR after RP for PCa. Data on disease progression and PCa-specific mortality are limited. Heterogeneity among the studies was substantial.

CONCLUSIONS

The review shows that PI-RADS scores provide information on the future likelihood of cancer recurrence or progression, at least for men undergoing RP. We are of the view that this information should be taken into account to identify men at higher risk of unfavorable outcomes.

PATIENT SUMMARY

A higher Prostate Imaging-Reporting and Data System score for magnetic resonance imaging of the prostate seems to be positively associated with oncological failure in prostate cancer and should be incorporated into future risk models.

Differences in risk factors for biochemical recurrence after radical prostatectomy stratified by the degree of obesity: Focused on surgical methods

This study aims to evaluate differences in the risk factors for biochemical recurrence (BCR) for radical prostatectomy stratified by degree of obesity, focusing on the surgical method used. All 3099 patients who underwent radical prostatectomy in two medical centres from January 2008 to March 2018 were retrospectively reviewed. Patients were divided into three groups based on body mass index: ‘normal’, ‘overweight’, and ‘obese’. Risk factors associated with biochemical recurrence were compared between different degrees of obesity. We analysed the contributing risk factors of BCR-free survival using univariate and multivariable Cox hazard models. There were 378 (12.2%) and 1815 (58.6%) patients in the ‘obese’ and ‘overweight’ groups, respectively. Accordingly, 1324 patients underwent retropubic radical prostatectomy (RRP), and 1775 underwent robotic-assisted laparoscopic prostatectomy (RALP). Multivariable analysis showed that patients who underwent RALP had significantly lower BCR free survival in the ‘overweight’ and ‘obese’ groups than those who underwent RRP, with adjusted hazard ratios of 0.75 (95% CI 0.59–0.95, p-value = 0.01) and 0.55 (95% CI 0.33–0.90, p-value = 0.02), respectively. The degree of obesity was not directly associated with BCR-free survival. Robotic prostatectomy showed greater benefits in BCR-free survival than open prostatectomy in the ‘overweight’ and ‘obese’ groups.

Exome sequencing identified six copy number variations as a prediction model for recurrence of primary prostate cancers with distinctive prognosis

Background

Prostate cancer (PCa) is a common type of malignancy, which represents one of the leading causes of death among men worldwide. Copy number variations (CNVs) and gene fusions play important roles in PCa and may serve as markers for the prognosis of this condition.

Methods

We have presently conducted an analysis of CNVs and gene fusions in PCa, using whole exome sequencing (WES) data of primary tumors. For this, a cohort of 74 PCa patients, including 30 recurrent and 44 non-recurrent cases, were assessed during 5 years of follow-up.

Results

We have identified 66 CNVs that were specific to the primary tumor tissues from the recurrent PCa group. Most of duplicated genomic regions were located in 8q2, suggesting that this chromosomal region could be important for the prognosis of PCa. Meanwhile, we have developed a random forest model, using six selected CNVs, with an accuracy near 90% for predicting PCa recurrence according to a 10-fold cross validation. In addition, we have detected 16 recurrent oncogenic gene fusions in PCa. Among these, ALK (ALK receptor tyrosine kinase)-involved fusions were the most common type of gene fusion (n=7). Four of these fusions (i.e., EML4-ALK, STRN-ALK, CLTC-ALK, ETV6-ALK) were previously identified in other cancer types, while the remaining three gene fusions (FRYL-ALK, ABL1-ALK, and BCR-ALK) were here identified.

Conclusions

Our findings expand the current understanding in regard to prostate carcinogenesis. Current data might be further used for assay development as well as to predict PCa recurrence, using primary tissues.

Can We Improve the Preoperative Prediction of Prostate Cancer Recurrence With Multiparametric MRI?

INTRODUCTION

The use of multiparametric magnetic resonance imaging (mpMRI) to assess prostate cancer (PCa) has increased over the past decade. We aimed to assess if preoperative mpMRI lesion score, a variable routinely available for men undergoing pre-biopsy MRI, improves the performance of commonly used preoperative predictive models for PCa recurrence.

PATIENTS AND METHODS

We analyzed data from 372 patients with PCa treated with radical prostatectomy in 2012 to 2017 and assessed with pre-biopsy mpMRI within 6 months prior to surgery. Suspicious areas for cancer were scored on a standardized 5-point scale. Cox regression was used to assess the association between mpMRI score and the risk of postoperative biochemical recurrence. Two different models were tested accounting for factors included in the Kattan nomogram and in the D'Amico risk-classification.

RESULTS

Overall, 53% and 30% of patients were found with a lesion scored 4 or 5 at pre-biopsy mpMRI, respectively. Risk varied widely by mpMRI (29% 2-year risk of biochemical recurrence for a score of 5 vs. 5% for a score of 1-2), and mpMRI score was associated with large hazard ratios after adjusting for stage, grade, and prostate-specific antigen: 1.66, 1.96, and 2.71 for scores 3, 4, and 5, respectively. However, 95% confidence intervals were very wide (0.19-14.20, 0.26-14.65, and 0.36-20.55, respectively) and included 1.

CONCLUSIONS

Our data did not show that preoperative models, commonly used to assess PCa risk, were improved after including the pre-biopsy mpMRI score. However, the value of pre-biopsy mpMRI to improve preoperative risk models should be investigated in larger data sets.

Prediction of Organ-confined Disease in High- and Very-high-risk Prostate Cancer Patients Staged with Magnetic Resonance Imaging: Implications for Clinical Trial Design

BACKGROUND

High-risk (HR) prostate cancer (PCa) is a heterogeneous disease leading to difficulties in designing appropriate inclusion criteria for clinical trials.

OBJECTIVE

To describe clinical predictors of organ-confined disease in HR or very-high-risk (VHR) PCa patients staged with multiparametric magnetic resonance imaging with endorectal coil (mp-MRI-ER).

DESIGN, SETTING, AND PARTICIPANTS

We reviewed 366 HR/VHR PCa patients who had preoperative mp-MRI-ER, and underwent radical prostatectomy and extended pelvic lymph node dissection between 2006 and 2015.

INTERVENTION

Radical prostatectomy with preoperative mp-MRI-ER.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We used multivariable logistic regression modeling to assess for associations with ≤ pT2N0 stage and multivariable cox modeling to assess for associations with biochemical failure.

RESULTS AND LIMITATIONS

Of 366 patients, 132 had ≤ pT2N0 disease. For the entire cohort, negative staging mp-MRI-ER (odds ratio [OR] 1.73, 95% confidence interval [CI] 1.06-2.83, p =  0.03), lower prostate-specific antigen (PSA; OR 0.98, 95% CI 0.97-1.00, p =  0.02), and fewer cores of Gleason ≥8 cancer (OR 0.86, 95% CI 0.79-0.93, p =  0.0002) were associated with ≤pT2N0 disease. In HR patients only, negative mp-MRI-ER (OR 3.41, 95% CI 1.73-6.72, p =  0.0004) and fewer than four cores of Gleason ≥8 disease (OR 3.38, 95% CI 1.20-9.56, p =  0.02) were still associated with ≤pT2N0 disease. Lack of non-organ-confined disease on MRI was associated with superior biochemical recurrence-free survival (p =  0.02). Limitations of this study include lack of a central review or quality control of the MRI reporting.

CONCLUSIONS

In HR PCa, negative staging mp-MRI-ER, fewer positive cores of Gleason >8, and lower PSA were significant predictors of pathologic organ-confined disease. Improved prediction of organ-confined disease in HR patients may allow for their inclusion into studies evaluating treatments from which they would otherwise be excluded based solely on their HR status.

PATIENT SUMMARY

In patients with high-risk prostate cancer, prostate magnetic resonance imaging along with other clinical parameters may help determine which patients are likely to have disease confined to the prostate and thus be eligible for clinical trials that they otherwise might be excluded from based on their high-risk status alone.

Aberrant DOCK2, GRASP, HIF3A and PKFP Hypermethylation has Potential as a Prognostic Biomarker for Prostate Cancer

Prostate cancer (PCa) is a clinically heterogeneous disease and currently, accurate diagnostic and prognostic molecular biomarkers are lacking. This study aimed to identify novel DNA hypermethylation markers for PCa with future potential for blood-based testing. Accordingly, to search for genes specifically hypermethylated in PCa tissue samples and not in blood cells or other cancer tissue types, we performed a systematic analysis of genome-wide DNA methylation data (Infinium 450K array) available in the Marmal-aid database for 4072 malignant/normal tissue samples of various types. We identified eight top candidate markers (cg12799885, DOCK2, FBXO30, GRASP, HIF3A, MOB3B, PFKP, and TPM4) that were specifically hypermethylated in PCa tissue samples and hypomethylated in other benign and malignant tissue types, including in peripheral blood cells. Potential as diagnostic and prognostic biomarkers was further assessed by the quantitative methylation specific PCR (qMSP) analysis of 37 nonmalignant and 197 PCa tissue samples from an independent population. Here, all eight hypermethylated candidates showed high sensitivity (75–94%) and specificity (84–100%) for PCa. Furthermore, DOCK2, GRASP, HIF3A and PKFP hypermethylation was significantly associated with biochemical recurrence (BCR) after radical prostatectomy (RP; 197 patients), independent of the routine clinicopathological variables. DOCK2 is the most promising single candidate marker (hazard ratio (HR) (95% confidence interval (CI)): 1.96 (1.24–3.10), adjusted p = 0.016; multivariate cox regression). Further validation studies are warranted and should investigate the potential value of these hypermethylation candidate markers for blood-based testing also.