Association of rare, recurrent nonsynonymous variants in the germline of prostate cancer patients of African ancestry

BACKGROUND

Although men of African ancestry (AA) have the highest mortality rate from prostate cancer (PCa), relatively little is known about the germline variants that are associated with PCa risk in AA men. The goal of this study is to systematically evaluate rare, recurrent nonsynonymous variants across the exome for their association with PCa in AA men.

METHODS

Whole exome sequencing (WES) of germline DNA in two AA PCa patient cohorts of Johns Hopkins Hospital (N = 960) and Wayne State University (N = 747) was performed. All nonsynonymous variants present in both case cohorts, with a carrier rate between 0.5% and 1%, were identified. Their carrier rates were compared with rates from 8128 African/African American (AFR) control subjects from The Genome Aggregation Database (gnomAD) using Fisher's exact test. Significant variants, defined as false discovery rate (FDR) adjusted p-value ≤ 0.05, were further evaluated in AA PCa cases (N = 132) and controls (N = 1184) from the UK Biobank (UKB).

RESULTS

Two variants reached a pre-specified statistical significance level. The first was p.R14Q in GPRC5C (found in 0.47% of PCa cases and 0.01% of population controls); odds ratio (OR) for PCa was 37.46 (95% confidence interval CI 4.68-299.72), p_exact  = 7.01E-06, FDR-adjusted p-value = 0.05. The second was p.R511Q in IGF1R (found in 0.53% of PCa cases and 0.01% of population controls); OR for PCa was 21.54 (95%CI 4.65-99.76), p_exact  = 5.51E-06, FDR-adjusted p-value = 0.05. The mean percentage of African ancestry was similar between variant carriers and noncarriers of each variant, p > 0.05. In the UKB AA men, GPRC5C R14Q was 0.76% and 0.08% in cases and controls, respectively, OR for PCa was 9.00 (95%CI 0.56-145.23), p_exact  = 0.19. However, IGF1R R511Q was not found in cases or controls.

CONCLUSIONS

This WES study identified two rare, recurrent nonsynonymous PCa risk-associated variants in AA. Confirmation in additional large populations of AA PCa cases and controls is required.

A Rare Germline HOXB13 Variant Contributes to Risk of Prostate Cancer in Men of African Ancestry

A rare African ancestry-specific germline deletion variant in HOXB13 (X285K, rs77179853) was recently reported in Martinican men with early-onset prostate cancer. Given the role of HOXB13 germline variation in prostate cancer, we investigated the association between HOXB13 X285K and prostate cancer risk in a large sample of 22 361 African ancestry men, including 11 688 prostate cancer cases. The risk allele was present only in men of West African ancestry, with an allele frequency in men that ranged from 0.40% in Ghana and 0.31% in Nigeria to 0% in Uganda and South Africa, with a range of frequencies in men with admixed African ancestry from North America and Europe (0-0.26%). HOXB13 X285K was associated with 2.4-fold increased odds of prostate cancer (95% confidence interval [CI] = 1.5-3.9, p = 2 × 10^-4), with greater risk observed for more aggressive and advanced disease (Gleason ≥8: odds ratio [OR] = 4.7, 95% CI = 2.3-9.5, p = 2 × 10^-5; stage T3/T4: OR = 4.5, 95% CI = 2.0-10.0, p = 2 × 10^-4; metastatic disease: OR = 5.1, 95% CI = 1.9-13.7, p = 0.001). We estimated that the allele arose in West Africa 1500-4600 yr ago. Further analysis is needed to understand how the HOXB13 X285K variant impacts the HOXB13 protein and function in the prostate. Understanding who carries this mutation may inform prostate cancer screening in men of West African ancestry. PATIENT SUMMARY: A rare African ancestry-specific germline deletion in HOXB13, found only in men of West African ancestry, was reported to be associated with an increased risk of overall and advanced prostate cancer. Understanding who carries this mutation may help inform screening for prostate cancer in men of West African ancestry.

Association of prostate cancer polygenic risk score with number and laterality of tumor cores in active surveillance patients

BACKGROUND

Prostate cancer (PCa) is characterized by its tendency to be multifocal. However, few studies have investigated the endogenous factors that explain the multifocal disease. The primary objective of the current study is to test whether inherited PCa risk is associated with multifocal tumors in PCa patients.

METHODS

Subjects in this study were PCa patients of European ancestry undergoing active surveillance at Johns Hopkins Hospital (N = 805) and NorthShore University HealthSystem (N = 432). The inherited risk was measured by genetic risk score (GRS), an odds ratio-weighted and population-standardized polygenic risk score based on known risk-associated single nucleotide polymorphisms. PCa multifocality was indirectly measured by the number and laterality of positive tumor cores from a 12-core systematic biopsy.

RESULTS

In the combined cohort, 35.7% and 66.3% of patients had ≥2 tumor cores at the initial diagnostic biopsy and on at least one subsequent surveillance biopsy, respectively. For tumor laterality, 7.8% and 47.8% of patients had bilateral tumor cores at diagnostic and surveillance biopsies, respectively. We found, for the first time, that patients with higher numbers of positive cores at diagnostic and surveillance biopsies, respectively, had significantly higher mean GRS values; p = .01 and p = 5.94E-04. Additionally, patients with bilateral tumors at diagnostic and surveillance biopsies, respectively, had significantly higher mean GRS values than those with unilateral tumors; p = .04 and p = .01. In contrast, no association was found between GRS and maximum core length of tumor or tumor grade at diagnostic/surveillance biopsies (all p > .05). Finally, we observed a modest trend that patients with higher GRS quartiles had a higher risk for tumor upgrading on surveillance biopsies. The trend, however, was not statistically significant (p > .05).

CONCLUSIONS

The associations of GRS with two measurements of PCa multifocality (core numbers and laterality) provide novel and consistent evidence for the link between inherited PCa risk and multifocal tumors.

A Germline Variant at 8q24 Contributes to Familial Clustering of Prostate Cancer in Men of African Ancestry

Although men of African ancestry have a high risk of prostate cancer (PCa), no genes or mutations have been identified that contribute to familial clustering of PCa in this population. We investigated whether the African ancestry-specific PCa risk variant at 8q24, rs72725854, is enriched in men with a PCa family history in 9052 cases, 143 cases from high-risk families, and 8595 controls of African ancestry. We found the risk allele to be significantly associated with earlier age at diagnosis, more aggressive disease, and enriched in men with a PCa family history (32% of high-risk familial cases carried the variant vs 23% of cases without a family history and 12% of controls). For cases with two or more first-degree relatives with PCa who had at least one family member diagnosed at age <60 yr, the odds ratios for TA heterozygotes and TT homozygotes were 3.92 (95% confidence interval [CI] = 2.13-7.22) and 33.41 (95% CI = 10.86-102.84), respectively. Among men with a PCa family history, the absolute risk by age 60 yr reached 21% (95% CI = 17-25%) for TA heterozygotes and 38% (95% CI = 13-65%) for TT homozygotes. We estimate that in men of African ancestry, rs72725854 accounts for 32% of the total familial risk explained by all known PCa risk variants. PATIENT SUMMARY: We found that rs72725854, an African ancestry-specific risk variant, is more common in men with a family history of prostate cancer and in those diagnosed with prostate cancer at younger ages. Men of African ancestry may benefit from the knowledge of their carrier status for this genetic risk variant to guide decisions about prostate cancer screening.

Rare Germline Pathogenic Mutations of DNA Repair Genes Are Most Strongly Associated with Grade Group 5 Prostate Cancer

BACKGROUND

Rare germline mutations in several genes, primarily DNA repair genes, have been proposed to predict worse prognosis of prostate cancer (PCa).

OBJECTIVE

To compare the frequency of germline pathogenic mutations in commonly assayed PCa genes between high- and low-grade PCa in patients initially presenting with clinically localized disease.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective case-case study of 1694 PCa patients who underwent radical prostatectomy at Johns Hopkins Hospital, including 706 patients with high-grade (grade group [GG] 4 and GG5) and 988 patients with low-grade (GG1) disease. Germline DNA was sequenced for 13 candidate PCa genes using a targeted next-generation sequencing assay by Ambry Genetics.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Carrier rates of pathogenic mutations were compared between high- and low-grade PCa patients using the Fisher's exact test.

RESULTS AND LIMITATIONS

Overall, the carrier rate of germline pathogenic mutations in the 13 genes was significantly higher in high-grade patients (8.64%) than in low-grade patients (3.54%, p = 9.98 × 10^-6). Individually, significantly higher carrier rates for patients with high- versus low-grade PCa were found for three genes: ATM (2.12% and 0.20%, respectively, p = 9.35 × 10^-5), BRCA2 (2.55% and 0.20%, respectively, p = 8.99 × 10^-6), and MSH2 (0.57% and 0%, respectively, p = 0.03). The mutation carrier rate was significantly higher in patients with GG5 than in patients with GG1 disease for the 13 genes overall (13.07% and 3.54%, respectively, p = 1.27 × 10^-9); for the three genes ATM, BRCA2, and MSH2 (7.73% and 0.40%, respectively, p = 3.20 × 10^-13); and for the remaining nine DNA repair genes (5.07% and 2.43%, respectively, p = 0.02).

CONCLUSIONS

In men undergoing treatment for clinically localized disease, pathogenic mutations in 13 commonly assayed genes, especially ATM, BRCA2, and MSH2, are most strongly associated with GG5 PCa. These findings emphasize the importance of genetic testing in men with high-grade PCa, particularly GG5 disease, to inform both treatment decisions and familial risk assessment.

PATIENT SUMMARY

Prostate cancer in men with inherited mutations in 13 commonly assayed susceptibility genes is more likely to be high-grade, high-risk disease.

PSA Doubling Time and Absolute PSA Predict Metastasis-free Survival in Men With Biochemically Recurrent Prostate Cancer After Radical Prostatectomy

INTRODUCTION

The aim of this study was to investigate the association of prostate-specific antigen (PSA) values on metastasis-free survival (MFS) in men with biochemically recurrent prostate cancer (BRPC) and PSA doubling time (PSADT) < 12 months. This dataset also reflects an update with longer follow-up of our prior publications on the natural history of BRPC in the absence of treatment.

MATERIALS AND METHODS

In this report, we combined databases from the Center for Prostate Disease Research and Johns Hopkins University (CPDR/JHU). In the CPDR/JHU radical prostatectomy database (30,936 total patients), 656 men with BRPC (> 0.2 ng/mL) after prostatectomy and PSADT < 12 months, who received no adjuvant/salvage androgen deprivation and/or radiation therapy, were prospectively followed until radiologic evidence of metastasis and are included in this analysis.

RESULTS

Metastasis occurred in 250 of 656 patients with BRPC (median follow-up, 5 years). PSADT < 7.5 months and Gleason score were independent risk factors for distant metastasis in multivariable analysis. Risk of metastasis increased for PSADT 6.01 to 7.50, 4.51 to 6.0, 3.01 to 4.50, and ≤ 3.0 months, after adjusting for Gleason score. A PSA value ≥ 0.5 ng/mL significantly and independently increased risk of metastasis in patients with PSADT < 12 months (hazard ratio, 2.79; 95% confidence interval, 1.47-5.29; P = .001).

CONCLUSIONS

In men with PSADT < 12 months, PSADT ≤ 7.5 months, PSA ≥ 0.5 ng/mL, and Gleason score are independent predictors of MFS on multivariable analysis.

Germline mutations in PPFIBP2 are associated with lethal prostate cancer

BACKGROUND

Few genes have germline mutations which predispose men to more aggressive prostate cancer (PCa). This study evaluated the contribution of germline loss of function (LOF) variants in PPFIBP2 to risk of lethal PCa.

METHODS

A case-case study of 1414 PCa patients with lethal PCa and low-risk localized PCa was performed. Germline DNA samples from these patients were sequenced for PPFIBP2. Mutation carrier rates and association with lethal PCa were analyzed using the Fisher exact test, logistic regression, and Kaplan-Meier survival analysis.

RESULTS

In the entire study population, eight patients, all of European ancestry, were identified as carrying PPFIBP2 pathogenic or likely pathogenic mutations. Seven (1.52%) of 462 lethal PCa patients were carriers compared with only one (0.12%) carrier in 810 low-risk PCa patients, P = 0.0029. The estimated Odds Ratio (OR) of carrying PPFIBP2 mutation for lethal PCa was 13.8 in European American population. The PPFIBP2 loss-of-function mutation carrier rate in lethal PCa cases was also higher than in 33 370 non-Finnish European individuals from the Exome Aggregation Consortium (ExAC) (carrier rate of 0.17%, P = 1.92 × 10^-5 ) and in 498 men with localized PCa from The Cancer Genome Atlas cohort (TCGA) cohort (carrier rate of 0%, P = 0.0058). Survival analysis in European American lethal cases revealed PPFIBP2 mutation status as an independent predictor of shorter survival after adjusting for age at diagnosis, PSA at diagnosis, and genetic background (hazard ratio = 2.62, P = 0.034).

CONCLUSIONS

While larger studies are needed, germline mutations in a novel gene, PPFIBP2, differentiated risk for lethal PCa from low-risk cases and were associated with shorter survival times after diagnosis.

Differences in inherited risk among relatives of hereditary prostate cancer patients using genetic risk score

PURPOSE

Family history assigns equivalent risk to all relatives based upon the degree of relationship. Recent genetic studies have identified single nucleotide polymorphisms (SNPs) that can be used to calculate a genetic risk score (GRS) to determine prostate cancer (PCa) risk. We sought to determine whether GRS can stratify PCa risk among individuals in families considered to be at higher risk due their family history of PCa.

MATERIALS AND METHODS

Family members with hereditary PCa were recruited and genotyped for 17 SNPs associated with PCa. A GRS was calculated for all subjects. Analyses compared the distribution of GRS values among affected and unaffected family members of varying relationship degrees.

RESULTS

Data was available for 789 family members of probands including 552 affected and 237 unaffected relatives. Median GRSs were higher among first-degree relatives compared to second- and third-degree relatives. In addition, GRS values among affected first- and second-degree relatives were significantly higher than unaffected relatives (P = 0.042 and P = 0.016, respectively). Multivariate analysis including GRS and degree of relationship demonstrated that GRS was a significant and independent predictor of PCa (OR 1.52, 95%CI 1.15-2.01).

CONCLUSION

GRS is an easy-to-interpret, objective measure that can be used to assess differences in PCa risk among family members of affected men. GRS allows for further differentiation among family members, providing better risk assessment. While prospective validation studies are required, this information can help guide relatives in regards to the time of initiation and frequency of PCa screening.

Role of Genetic Testing for Inherited Prostate Cancer Risk: Philadelphia Prostate Cancer Consensus Conference 2017

Purpose Guidelines are limited for genetic testing for prostate cancer (PCA). The goal of this conference was to develop an expert consensus-driven working framework for comprehensive genetic evaluation of inherited PCA in the multigene testing era addressing genetic counseling, testing, and genetically informed management. Methods An expert consensus conference was convened including key stakeholders to address genetic counseling and testing, PCA screening, and management informed by evidence review. Results Consensus was strong that patients should engage in shared decision making for genetic testing. There was strong consensus to test HOXB13 for suspected hereditary PCA, BRCA1/2 for suspected hereditary breast and ovarian cancer, and DNA mismatch repair genes for suspected Lynch syndrome. There was strong consensus to factor BRCA2 mutations into PCA screening discussions. BRCA2 achieved moderate consensus for factoring into early-stage management discussion, with stronger consensus in high-risk/advanced and metastatic setting. Agreement was moderate to test all men with metastatic castration-resistant PCA, regardless of family history, with stronger agreement to test BRCA1/2 and moderate agreement to test ATM to inform prognosis and targeted therapy. Conclusion To our knowledge, this is the first comprehensive, multidisciplinary consensus statement to address a genetic evaluation framework for inherited PCA in the multigene testing era. Future research should focus on developing a working definition of familial PCA for clinical genetic testing, expanding understanding of genetic contribution to aggressive PCA, exploring clinical use of genetic testing for PCA management, genetic testing of African American males, and addressing the value framework of genetic evaluation and testing men at risk for PCA-a clinically heterogeneous disease.

Prostate Specific Antigen Testing after Radical Prostatectomy-Can We Stop at 20 Years?

PURPOSE

We examined the clinical features and outcomes associated with delayed biochemical recurrence after radical prostatectomy, specifically among men with more than 20 years of followup.

MATERIALS AND METHODS

A total of 16,720 men underwent radical prostatectomy and 2,699 experienced biochemical recurrence. We determined predictors of delayed biochemical recurrence as well as metastasis-free and cancer specific survival rates for recurrence at various time points after radical prostatectomy. We performed subset analysis of the 732 men with 20 or more years of recurrence-free followup. Cumulative incidence curves for metastasis and prostate cancer death were calculated and stratified by biochemical recurrence time points.

RESULTS

Predictors of delayed biochemical recurrence included elevated prostate specific antigen at radical prostatectomy, higher clinical and pathological stage, and positive surgical margins. Delayed biochemical recurrence was associated with favorable cumulative incidence curves for metastasis and prostate cancer death compared to early biochemical recurrence. Among the 732 men with undetectable prostate specific antigen at 20 years biochemical recurrence developed in 17 (2.3%), metastatic disease developed in a single patient and none died of prostate cancer. The actuarial probability of biochemical recurrence among men with undetectable prostate specific antigen at 20 years increased with adverse pathological features.

CONCLUSIONS

Men with delayed biochemical recurrence have favorable clinical features and improved survival. Men with undetectable prostate specific antigen 20 years after radical prostatectomy had a low rate of recurrence and no deaths from prostate cancer. This suggests that 20 years is a reasonable time to discontinue prostate specific antigen testing.

A genetic variant near GATA3 implicated in inherited susceptibility and etiology of benign prostatic hyperplasia (BPH) and lower urinary tract symptoms (LUTS)

BACKGROUND

Benign prostatic hyperplasia (BPH) and associated lower urinary tract symptoms (LUTS) are common conditions. Little is known about their etiologies except that studies have suggested a substantial heritable component. Our objective is to provide a comprehensive, genome-wide evaluation of inherited risks and possible mechanisms of etiology in BPH.

METHODS

We performed a three-stage, genome-wide association study (GWAS) of men from three independent populations, the REduction by DUtasteride of prostate Cancer Events (REDUCE) trial, the CLUE II cohort, and a Finnish hospital-based population. DNA samples were genotyped using the Illumina HumanOmniExpress BeadChip in REDUCE and CLUE II, and using the Sequenom iPLEX system for the confirmation stage in the Finnish population. A logistic regression model was used to evaluate the association between each SNP and BPH/LUTS.

RESULTS

Fourteen SNPs reached P < 5.0 × 10^-4 in the meta-analysis of the two GWASs (CLUE II and REDUCE). A total of 773 SNPs were chosen for the confirmation step in the Finish cohort. Only one SNP (rs17144046) located ∼489 kb downstream of GATA3 remained significant after correction for multiple testing (P < 6.5 × 10^-5 ). This SNP marginally reached the GWAS significance level after performing a meta-analysis of the three stages (P_-meta  = 8.89 × 10^-7 ). Expression quantitative trait loci (eQTL) analyses showed that the risk allele (G) of rs17144046 was significantly associated with increased expression of GATA3 (P = 0.017). Reported studies indicated a close correlation between GATA3 and BPH pathogenesis and progression.

CONCLUSIONS

Rs17144046 located near GATA3 was significantly associated with BPH/LUTS in three independent populations, but did not reach a stringent GWAS significance level. Genetic variants of GATA3 may play a role in the inherited susceptibility and etiology of BPH/LUTS. Further research in this area is needed.

Abstract 5324: ERG expression and PTEN loss by BMI and weight change in men with prostate cancer

Background: Obesity and weight gain are associated with poor prostate cancer outcome; underlying mechanisms are unknown. Obesity has been more strongly associated with lethal disease in men positive for the TMPRSS2:ERG gene fusion than negative for this fusion. PTEN loss is associated with increased risk of lethal progression; its association with obesity has not been explored. We evaluated whether prevalence of ERG expression and PTEN loss in prostate tumors differs by BMI and weight change.

Methods: From a retrospective cohort study of 1,337 men with clinically-localized prostate cancer who underwent prostatectomy at Johns Hopkins (1993-2006), we sampled 291 men by combination of BMI at 1 year after surgery (normal, overweight, obese) and weight change from 5 years before to 1 year after surgery (loss, maintenance, gain). Within each category, men were frequency-matched on age, Gleason sum, organ confinement, and surgery year. We used genetically validated immunohistochemistry assays to assess ERG positivity and heterogeneous PTEN loss. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association of BMI and weight change (adjusted for height, starting weight) with ERG positivity and heterogeneous PTEN loss.

Results: Mean age was 56.1 years and mean Gleason sum was 6.2; 73% had organ-confined disease. Prevalence of ERG positivity did not statistically significantly differ by BMI or weight change. However, when jointly categorized by BMI and weight change, overweight/obese men who maintained (OR=2.5; 95%CI 1.1-5.7) or gained weight (OR=2.5; 95%CI 1.1-5.8), and normal weight men who gained weight (OR=4.7; 95%CI 1.4-15.2) were significantly more likely to have ERG positive tumors compared with normal weight men who maintained weight. Overweight/obese men were also significantly more likely (OR=2.4; 95%CI 1.3-4.7) to have PTEN loss compared with normal weight men. When stratified by ERG status, this association appeared to be stronger for men with ERG positive tumors (OR=2.9; 95%CI 1.3-6.8) than for men with ERG negative tumors (OR=1.6; 95%CI 0.6-4.9). Prevalence of PTEN loss did not differ by weight change. When jointly categorized by BMI and weight change, overweight/obese men who maintained (OR=2.0; 95%CI 0.8-5.3) or gained weight (OR=1.9; 95%CI 0.7-5.1) appeared to be more likely to have PTEN loss compared with normal weight men who maintained weight.

Conclusions: Overweight/obese men who maintained or gained weight circa diagnosis and normal weight men who gained weight were more likely to have ERG positive tumors. Overweight/obese men were more likely to have tumors with PTEN loss; this association was stronger among overweight/obese men who also had ERG positive tumors. The TMPRSS2:ERG gene fusion and PTEN loss may contribute to the increased risk of poor prostate cancer outcomes among overweight/obese men. Funding: Prostate Cancer Foundation

Citation Format: Janelle S. Ho, Ibrahim Kulac, Tamara L. Lotan, John R. Barber, Patrick C. Walsh, Misop Han, Angelo M. De Marzo, Elizabeth A. Platz, Corinne E. Joshu. ERG expression and PTEN loss by BMI and weight change in men with prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5324. doi:10.1158/1538-7445.AM2017-5324

Stereotactic ablative radiation therapy for the treatment of oligometastatic prostate cancer

5020

Background: The importance of local treatment in oligometastatic prostate cancer (OPC) is unknown. Stereotactic ablative radiotherapy (SABR) is highly focused, high-dose radiation that is well suited for treatment of oligometastases. Here we report on the safety and preliminary clinical outcomes of SABR in a modern cohort of OPC men. Methods: Eighty four men who satisfied criteria of OPC diagnosed on imaging underwent consolidative SABR were then followed prospectively on our IRB approved registry by our GU multidisciplinary team. We collected demographic, clinical, toxicity and efficacy information. We examined the first 66 men in this preliminary report to allow for a minimum of 4.5 months follow-up. SABR was delivered in 1-5 fractions of 5-18 Gy. Kaplan-Meier method was used to assess local progression-free survival (LPFS), biochemical progression-free survival (bPFS; PSA nadir+2), distant progression free survival (DPFS), ADT-free survival (ADT-FS) and time-to-next intervention (TTNI). Results: Of the 66 OPC patients analyzed, 25 (38%) men presented as synchronous OPC and the remaining 41 had recurrent OPC. Median and mean follow-up was 61 and 66 weeks, respectively. Patient and disease factors as listed in the Table. Crude Grade 1 and 2 acute toxicities were 36% and 11%, respectively, with no Grade > 2 toxicity. SABR was delivered to 134 metastases: 89 bone (66%), 40 nodal (30%) and 5 (4%) visceral metastases. Overall LPFS at 1-year was 92%. The bPFS and DPFS at 1-year were 69% and 69%, respectively. Median TTNI was not reached yet. Of the 18 men with hormone sensitive prostate cancer who had their ADT deferred, 11/18 (56%) remain free of disease following SABR (1-year ADT-FS was 78%) and in 17 castration resistant men, 11 had > 50% PSA declines with 1-year TTNI of 30% with a median of 45 weeks. Conclusions: Consolidative SABRfor OPCis feasible and well tolerated. The preliminary clinical outcomes in our series is limited by heterogeneity and size but our data suggests that this approach is worthy of further prospective study. [Table: see text]

Unscreened older men diagnosed with prostate cancer are at increased risk of aggressive disease

BACKGROUND

To evaluate the relationship between PSA testing history and high-risk disease among older men diagnosed with prostate cancer.

METHODS

Records from 1993 to 2014 were reviewed for men who underwent radiotherapy for prostate cancer at age 75 years or older. Patients were classified into one of four groups based on PSA-testing history: (1) no PSA testing; (2) incomplete/ineffective PSA testing; (3) PSA testing; or (4) cannot be determined. Outcomes of interest were National Comprehensive Cancer Network (NCCN) risk group (that is, low, intermediate or high risk) and biopsy grade at diagnosis. Multivariable logistic regression was used to determine the association between PSA testing history and high-risk cancer.

RESULTS

PSA-testing history was available in 274 (94.5%) of 290 subjects meeting study criteria. In total, 148 men (54.0%) underwent PSA testing with follow-up biopsy, 72 (26.3%) underwent PSA testing without appropriate follow-up, and 54 men (19.7%) did not undergo PSA testing. Patients who underwent PSA testing were significantly less likely to be diagnosed with NCCN high-risk cancer (23.0% vs 51.6%, P<0.001). On multivariable analysis, men with no/incomplete PSA testing had more than three-fold increased odds of high-risk disease at diagnosis (odds ratio 3.39, 95% confidence interval 1.96-5.87, P<0.001) as compared to the tested population.

CONCLUSIONS

Older men who underwent no PSA testing or incomplete testing were significantly more likely to be diagnosed with high-risk prostate cancer than those who were previously screened. It is reasonable to consider screening in healthy older men likely to benefit from early detection and treatment.

Impotence Following Radical Prostatectomy: Insight into Etiology and Prevention

This study was undertaken to identify the cause of impotence in men undergoing radical prostatectomy, with the hope that this information may provide insight into the possible prevention of this complication. The autonomic innervation of the corpora cavernosa in the male fetus and newborn was traced to determine the topographical relationship between the pelvic nerve plexus, and the prostate, urethra and urogenital diaphragm. We have demonstrated that the branches of the pelvic plexus that innervate the corpora cavernosa are situated between the rectum and urethra, and penetrate the urogenital diaphragm near or in the muscular wall of the urethra. Injuries to the pelvic plexus can occur in 2 ways: 1) during division of the lateral pedicle and 2) at the time of apical dissection with transection of the urethra. Thirty-one men who underwent radical retropubic prostatectomy were evaluated to determine risk factors that correlated with postoperative impotence: 5 (16 per cent) were fully potent, 7 (23 per cent) had partial erections that were inadequate for sexual intercourse and 19 (61 per cent) had total erectile impotence. The 2 factors that had a favorable influence on postoperative potency were age and pathologic stage of the lesion: 31 per cent of the patients less than 60 years old were potent versus only 6 per cent of the patients more than 60 years, while 33 per cent of the patients with tumor microscopically confined to the prostatic capsule were potent versus only 5 per cent of those with capsular penetration. When the factors of age and capsular penetration were combined 60 per cent of the men less than 60 years old who had an intact prostatic capsule were potent. Arterial insufficiency and psychogenic factors were excluded as major contributing factors by the finding of normal penile blood flow and absence of nocturnal penile tumescence in the impotent patients. We conclude that impotence after radical prostatectomy results from injury to the pelvic nerve plexus that provides autonomic innervation to the corpora cavernosa. Further studies will be necessary to determine whether refinements in surgical technique, especially during ligation of the lateral pedicle and apical dissection, can prevent this complication.

Technique and outcomes of bladder neck intussusception during robot-assisted laparoscopic prostatectomy: A parallel comparative trial

INTRODUCTION

Postprostatectomy incontinence significantly impairs quality of life. Although bladder neck intussusception has been reported to accelerate urinary recovery after open radical retropubic prostatectomy, its adaption to robotic surgery has not been assessed. Accordingly, we describe our technique and compare outcomes between men treated with and without bladder neck intussusception during robot-assisted laparoscopic prostatectomy.

MATERIALS AND METHODS

We performed a comparative trial of 48 men undergoing robot-assisted laparoscopic prostatectomy alternating between bladder neck intussusception (n = 24) and nonintussusception (n = 24). Intussusception was completed using 3-0 polyglycolic acid horizontal mattress sutures anterior and posterior to the bladder neck. We assessed baseline characteristics and clinicopathologic outcomes. Adjusting for age, body mass index, race, and D׳Amico risk classification, we prospectively compared urinary function at 2 days, 2 weeks, 2 months, and last follow-up using the urinary domain of the Expanded Prostate Cancer Index-Short Form.

RESULTS

Baseline patient characteristics and clinicopathologic outcomes were similar between treatment groups (P>0.05). Median catheter duration (8 vs. 8d, P = 0.125) and rates of major postoperative complications (4.2% vs. 4.2%, P = 1.000) did not differ. In adjusted analyses, Expanded Prostate Cancer Index-Short Form urinary scores were significantly higher for the intussusception arm at 2 weeks (65.4 vs. 46.6, P = 0.019) before converging at 2 months (69.1 vs. 68.3, P = 0.929) after catheter removal and at last follow-up (median = 7mo, 80.5 vs. 77.0; P = 0.665).

CONCLUSIONS

Bladder neck intussusception during robot-assisted laparoscopic prostatectomy is feasible and safe. Although the long-term effects appear limited, intussusception may improve urinary function during the early recovery period.

Genome-wide association of familial prostate cancer cases identifies evidence for a rare segregating haplotype at 8q24.21

Previous genome-wide association studies (GWAS) of prostate cancer risk focused on cases unselected for family history and have reported over 100 significant associations. The International Consortium for Prostate Cancer Genetics (ICPCG) has now performed a GWAS of 2511 (unrelated) familial prostate cancer cases and 1382 unaffected controls from 12 member sites. All samples were genotyped on the Illumina 5M+exome single nucleotide polymorphism (SNP) platform. The GWAS identified a significant evidence for association for SNPs in six regions previously associated with prostate cancer in population-based cohorts, including 3q26.2, 6q25.3, 8q24.21, 10q11.23, 11q13.3, and 17q12. Of note, SNP rs138042437 (p = 1.7e(-8)) at 8q24.21 achieved a large estimated effect size in this cohort (odds ratio = 13.3). 116 previously sampled affected relatives of 62 risk-allele carriers from the GWAS cohort were genotyped for this SNP, identifying 78 additional affected carriers in 62 pedigrees. A test for an excess number of affected carriers among relatives exhibited strong evidence for co-segregation of the variant with disease (p = 8.5e(-11)). The majority (92 %) of risk-allele carriers at rs138042437 had a consistent estimated haplotype spanning approximately 100 kb of 8q24.21 that contained the minor alleles of three rare SNPs (dosage minor allele frequencies <1.7 %), rs183373024 (PRNCR1), previously associated SNP rs188140481, and rs138042437 (CASC19). Strong evidence for co-segregation of a SNP on the haplotype further characterizes the haplotype as a prostate cancer predisposition locus.

Infectious mononucleosis, other infections and prostate-specific antigen concentration as a marker of prostate involvement during infection

Although Epstein-Barr virus has been detected in prostate tissue, no associations have been observed with prostate cancer in the few studies conducted to date. One possible reason for these null findings may be use of cumulative exposure measures that do not inform the timing of infection, i.e., childhood versus adolescence/early adulthood when infection is more likely to manifest as infectious mononucleosis (IM). We sought to determine the influence of young adult-onset IM on the prostate by measuring prostate-specific antigen (PSA) as a marker of prostate inflammation/damage among U.S. military members. We defined IM cases as men diagnosed with IM from 1998 to 2003 (n = 55) and controls as men without an IM diagnosis (n = 255). We selected two archived serum specimens for each participant, the first collected after diagnosis for cases and one randomly selected from 1998 to 2003 for controls (index), as well as the preceding specimen (preindex). PSA was measured in each specimen. To explore the specificity of our findings for prostate as opposed to systemic inflammation, we performed a post hoc comparison of other infectious disease cases without genitourinary involvement (n = 90) and controls (n = 220). We found that IM cases were more likely to have a large PSA rise than controls (≥ 20 ng/mL: 19.7% versus 8.8%, p = 0.027; ≥ 40% rise: 25.7% versus 9.4%, p = 0.0021), as were other infectious disease cases (25.7% versus 14.0%, p = 0.020; 27.7% versus 18.0%, p = 0.092). These findings suggest that, in addition to rising because of prostate infection, PSA may also rise because of systemic inflammation, which could have implications for PSA interpretation in older men.

Immediate Adjuvant Radiation Therapy Following Radical Prostatectomy Should Not Be Advised for Men with Extraprostatic Extension Who Have Negative Surgical Margins

Although three large randomized prospective clinical trials have demonstrated that postoperative radiotherapy in patients with adverse pathological features reduces prostate-specific antigen recurrence and may decrease clinical failure, this approach has not gained widespread acceptance, likely because the data strongly support such an approach only in men with Gleason ≥7 with positive surgical margins.

Utility of Risk Models in Decision Making After Radical Prostatectomy: Lessons from a Natural History Cohort of Intermediate- and High-Risk Men

BACKGROUND

Current guidelines suggest adjuvant radiation therapy for men with adverse pathologic features (APFs) at radical prostatectomy (RP). We examine at-risk men treated only with RP until the time of metastasis.

OBJECTIVE

To evaluate whether clinicopathologic risk models can help guide postoperative therapeutic decision making.

DESIGN, SETTING, AND PARTICIPANTS

Men with National Comprehensive Cancer Network intermediate- or high-risk localized prostate cancer undergoing RP in the prostate-specific antigen (PSA) era were identified (n=3089). Only men with initial undetectable PSA after surgery and who received no therapy prior to metastasis were included. APFs were defined as pT3 disease or positive surgical margins.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Area under the receiver operating characteristic curve (AUC) for time to event data was used to measure the discrimination performance of the risk factors. Cumulative incidence curves were constructed using Fine and Gray competing risks analysis to estimate the risk of biochemical recurrence (BCR) or metastasis, taking censoring and death due to other causes into consideration.

RESULTS AND LIMITATIONS

Overall, 43% of the cohort (n=1327) had APFs at RP. Median follow-up for censored patients was 5 yr. Cumulative incidence of metastasis was 6% at 10 yr after RP for all patients. Cumulative incidence of metastasis among men with APFs was 7.5% at 10 yr after RP. Among men with BCR, the incidence of metastasis was 38% 5 yr after BCR. At 10 yr after RP, time-dependent AUC for predicting metastasis by Cancer of the Prostate Risk Assessment Postsurgical or Eggener risk models was 0.81 (95% confidence interval [CI], 0.72-0.97) and 0.78 (95% CI, 0.67-0.97) in the APF population, respectively. At 5 yr after BCR, these values were lower (0.58 [95% CI, 0.50-0.66] and 0.70 [95% CI, 0.63-0.76]) among those who developed BCR. Use of risk model cut points could substantially reduce overtreatment while minimally increasing undertreatment (ie, use of an Eggener cut point of 2.5% for treatment of men with APFs would spare 46% from treatment while only allowing for metastatic events in 1% at 10 yr after RP).

CONCLUSIONS

Use of risk models reduces overtreatment and should be a routine part of patient counseling when considering adjuvant therapy. Risk model performance is significantly reduced among men with BCR.

PATIENT SUMMARY

Use of current risk models can help guide decision making regarding therapy after surgery and reduce overtreatment.

Prostate cancer, version 1.2014

The NCCN Guidelines for Prostate Cancer provide multidisciplinary recommendations on the clinical management of patients with prostate cancer. This report highlights notable recent updates. Radium-223 dichloride is a first-in-class radiopharmaceutical that recently received approval for the treatment of patients with symptomatic bone metastases and no known visceral disease. It received a category 1 recommendation as both a first-line and second-line option. The NCCN Prostate Cancer Panel also revised recommendations on the choice of intermittent or continuous androgen deprivation therapy based on recent phase III clinical data comparing the 2 strategies in the nonmetastatic and metastatic settings.

The Melbourne Consensus Statement on the early detection of prostate cancer

Various conflicting guidelines and recommendations about prostate cancer screening and early detection have left both clinicians and their patients quite confused. At the Prostate Cancer World Congress held in Melbourne in August 2013, a multidisciplinary group of the world's leading experts in this area gathered together and generated this set of consensus statements to bring some clarity to this confusion. The five consensus statements provide clear guidance for clinicians counselling their patients about the early detection of prostate cancer.

Prevalence of the HOXB13 G84E prostate cancer risk allele in men treated with radical prostatectomy

OBJECTIVE

To determine the prevalence and clinical correlates of the G84E mutation in the homeobox transcription factor, or HOXB13, gene using DNA samples from 9559 men with prostate cancer undergoing radical prostatectomy.

PATIENTS AND METHODS

DNA samples from men treated with radical prostatectomy at the University of Michigan and John Hopkins University were genotyped for G84E and this was confirmed by Sanger sequencing. The frequency and distribution of this allele was determined according to specific patient characteristics (family history, age at diagnosis, pathological Gleason grade and stage).

RESULTS

Of 9559 patients, 128 (1.3%) were heterozygous carriers of G84E. Patients who possessed the variant were more likely to have a family history of prostate cancer than those who did not (46.0 vs 35.4%; P = 0.006). G84E carriers were also more likely to be diagnosed at a younger age than non-carriers (55.2 years vs 58.1 years; P < 0.001). No difference in the proportion of patients diagnosed with high grade or advanced stage tumours according to carrier status was observed.

CONCLUSIONS

In the present study, carriers of the rare G84E variant in HOXB13 were both younger at the time of diagnosis and more likely to have a family history of prostate cancer compared with homozygotes for the wild-type allele. No significant differences in allele frequency were detected according to selected clinical characteristics of prostate cancer. Further investigation is required to evaluate the role of HOXB13 in prostate carcinogenesis.

Association analysis of 9,560 prostate cancer cases from the International Consortium of Prostate Cancer Genetics confirms the role of reported prostate cancer associated SNPs for familial disease

Previous GWAS studies have reported significant associations between various common SNPs and prostate cancer risk using cases unselected for family history. How these variants influence risk in familial prostate cancer is not well studied. Here, we analyzed 25 previously reported SNPs across 14 loci from prior prostate cancer GWAS. The International Consortium for Prostate Cancer Genetics (ICPCG) previously validated some of these using a family-based association method (FBAT). However, this approach suffered reduced power due to the conditional statistics implemented in FBAT. Here, we use a case-control design with an empirical analysis strategy to analyze the ICPCG resource for association between these 25 SNPs and familial prostate cancer risk. Fourteen sites contributed 12,506 samples (9,560 prostate cancer cases, 3,368 with aggressive disease, and 2,946 controls from 2,283 pedigrees). We performed association analysis with Genie software which accounts for relationships. We analyzed all familial prostate cancer cases and the subset of aggressive cases. For the familial prostate cancer phenotype, 20 of the 25 SNPs were at least nominally associated with prostate cancer and 16 remained significant after multiple testing correction (p ≤ 1E (-3)) occurring on chromosomal bands 6q25, 7p15, 8q24, 10q11, 11q13, 17q12, 17q24, and Xp11. For aggressive disease, 16 of the SNPs had at least nominal evidence and 8 were statistically significant including 2p15. The results indicate that the majority of common, low-risk alleles identified in GWAS studies for all prostate cancer also contribute risk for familial prostate cancer, and that some may contribute risk to aggressive disease.

Anatomic extent of pelvic lymph node dissection: impact on long-term cancer-specific outcomes in men with positive lymph nodes at time of radical prostatectomy

OBJECTIVE

To evaluate the impact of an extended pelvic lymph node (LN) dissection (EPLND) on the oncologic outcomes of men with LN-positive prostate cancer.

METHODS

Patients were identified who underwent an open radical prostatectomy by one of two surgeons at the Johns Hopkins Hospital between 1992 and 2003. The first surgeon routinely performed a limited pelvic LN dissection (LPLND), whereas the second performed an EPLND. Men with positive LNs from each cohort were compared for differences in oncologic outcomes.

RESULTS

Positive LNs were found in 94 men (2.2%), 21 (22.3%) with an LPLND and 73 (77.7%) with an EPLND. On average, LPLND and EPLND yielded 11.4 and 14.6 nodes, respectively (P = .022). The two groups were similar in terms of the number of positive LNs (1.4 vs 1.8, P = .223) and the proportion of patients with <15% positive nodes (57.1% vs 69.9%, P = .300). At a median follow-up of 10.5 years, patients who underwent an EPLND had superior oncologic outcomes compared with the LPLND group: 5-year biochemical recurrence-free survival of 30.1% vs 7.1% (P = .018), 10-year metastasis-free survival of 62.2% vs 22.2% (P = .035), and 10-year cancer-specific survival of 83.6% vs 52.6% (P = .199). This analysis demonstrated an augmented improvement in biochemical recurrence-free survival in men with <15% positive nodes.

CONCLUSION

In addition to affording valuable staging information, an EPLND may confer a therapeutic benefit to patients found to have positive LNs at the time of radical prostatectomy.

Pathological and oncologic outcomes for men with positive lymph nodes at radical prostatectomy: The Johns Hopkins Hospital 30-year experience

BACKGROUND

We report the 30-year institutional experience of radical prostatectomy (RP) for men with clinically localized prostate cancer (PC) found to have lymph node (LN) metastases at surgery.

METHODS

The Johns Hopkins RP Database (1982-2011) was queried for 505 (2.5%) men with node-positive (N1) PC. Survival analysis was completed using the Kaplan-Meier method and proportional hazard regression models.

RESULTS

The proportion of men with N1PC was 8.3%, 3.5%, and 1.4% in the pre- (1982-1990), early- (1991-2000), and contemporary-PSA eras (2001-2011), respectively. A trend toward decreasing PSA, less palpable disease but more advanced Gleason sum was noted in the most contemporary era. Median total and positive nodes were 13.2 (1-41) and 1.7 (1-12), respectively. Of 135 patients with a unilateral tumor, 80 (59.3%), 28 (20.7%), and 15 (11.1%) had ipsilateral, contralateral, and bilateral positive LN. 15-year biochemical-recurrence free, metastases-free and cancer-specific survival was 7.1%, 41.5%, and 57.5%, respectively. Predictors of biochemical-recurrence, metastases and death from PC in multivariate analysis included Gleason sum at RP, the number and percent of positive LN; notably total number of LN dissected did not predict outcome.

CONCLUSIONS

In this highly-selected RP cohort, men found to have N1PC disease at RP can experience a durable long-term metastases-free and cancer-specific survival. Predictors of survival include Gleason sum, number, and percentage of positive LN. While total number of LN dissected was not predictive, approximately 30% of men with N1PC will have positive LN contralateral to the primary prostatic lesion highlighting the importance of a thorough, bilateral pelvic LN dissection.

Trends in immediate perioperative morbidity and delay in discharge after open and minimally invasive radical prostatectomy (RP): a 20-year institutional experience

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Standard clinical care pathways to discharge have been established for a number of operations including radical prostatectomy (RP). The pathway after RP has changed dramatically over the past two decades due to improvements in surgical technique, anaesthesia and most recently, the introduction of minimally invasive RP (MIRP). This study adds evidence that the emergence of MIRP is associated with a decrease in LOS for all patients undergoing RP. In addition, it catalogues the development of the clinical care pathway over 20 years at a large, tertiary care hospital with extensive experience in RP. Finally, it defines the common reasons patients fall 'off-pathway' (ileus, urine leak, anaemia and re-exploration for bleeding) and defines the immediate perioperative morbidity profile of RP. Specifically, it addresses approach-specific morbidities and indicates that MIRP is associated with higher rates of 'off-pathway' discharge, most often due to ileus.

OBJECTIVE

To investigate the development of the clinical care pathway to discharge after radical prostatectomy (RP) at a large, academic medical centre over the past 20 years, focusing on the rates and reasons for deviation.

PATIENTS AND METHODS

In all, 18 049 men were identified from the Johns Hopkins RP database who had undergone surgery since 1991. Patients in whom the length of stay (LOS) was ≤95th percentile, defined the clinical care pathway to discharge and those in whom LOS was ≥98th percentile were termed 'off-pathway'.

RESULTS

The mean LOS decreased from 7.7 days in 1991 to 1.6 days in 2010. Of 7126 patients undergoing RP since 2005, 1803(25.3%), 4881(68.5%) and 312 (4.4%) were discharged on postoperative day (POD) 1, 2 and 3, respectively; 126 (1.8%) patients, discharged on POD4-21 were 'off-pathway'. The most common reasons for delay of discharge were ileus (44, 0.615%), urine leak (12, 0.17%), anaemia requiring blood transfusion (nine, 0.126%) and bleeding requiring re-exploration (six, 0.08%). The proportion of patients 'off-pathway' was 1.20%, 1.06% and 4.01% for retropubic RP (RRP), laparoscopic RP (LRP) and robot-assisted laparoscopic RP (RALRP), respectively (P < 0.001). Ileus delayed discharge in 0.28%, 0.37% and 1.9% of patients undergoing RRP, LRP and RALRP, respectively (P < 0.001).

CONCLUSIONS

The clinical care pathway to discharge after RP has changed dramatically at our institution over the past 20 years. RALRP appears to result in a higher proportion of 'off-pathway' patients, primarily due to ileus, compared with RRP and LRP. However, very few patients were discharged 'off-pathway'.

Pathological outcomes in men with low risk and very low risk prostate cancer: implications on the practice of active surveillance

PURPOSE

We assessed oncologic outcomes at surgery in men with low risk and very low risk prostate cancer who were candidates for active surveillance.

MATERIALS AND METHODS

In a prospectively collected institutional database, we identified 7,486 subjects eligible for active surveillance who underwent radical retropubic prostatectomy. Candidates were designated as being at low risk (stage T1c/T2a, prostate specific antigen 10 ng/ml or less, and Gleason score 6 or less) or very low risk (stage T1c, prostate specific antigen density 0.15 or less, Gleason score 6 or less, 2 or fewer positive biopsy cores, 50% or less cancer involvement per core) based on preoperative data. Adverse findings were Gleason score upgrade (score 7 or greater) and nonorgan confined cancer on surgical pathology. The relative risk of adverse findings in men at low risk with very low risk disease was evaluated in a multivariate model using Poisson regression.

RESULTS

A total of 7,333 subjects met the criteria for low risk disease and 153 had very low risk disease. The proportion of subjects at low risk found to have Gleason score upgrade or nonorgan confined cancer on final pathology was 21.8% and 23.1%, respectively. Corresponding values in those at very low risk were 13.1% and 8.5%, respectively. After adjusting for age, race, year of surgery, body mass index, and prostate specific antigen at diagnosis, the relative risk of Gleason score upgrade in men with low risk vs very low risk disease was 1.89 (95% CI 1.21-2.95). The relative risk of nonorgan confined cancer was 2.06 (95% CI 1.19-3.57).

CONCLUSIONS

Men with very low risk prostate cancer were at significantly lower risk for adverse findings at surgery compared to those with low risk disease. These data support the stratification of low risk cancer when selecting and counseling men who may be appropriate for active surveillance.

Prognostic Gleason grade grouping: data based on the modified Gleason scoring system

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: The Gleason scoring system is a well-established predictor of pathological stage and oncological outcomes for men with prostate cancer. Modifications throughout the last few decades - most recently by the International Society of Urological Pathology (ISUP) in 2005 - have attempted to improve the correlation between biopsy and radical prostatectomy Gleason sum and better stratify patients to predict clinical outcomes. Based on these clinical outcomes and the excellent prognosis for patients with low Gleason scores, we recommend Gleason grades incorporating a prognostic grade grouping which accurately reflect prognosis and are clearly understood by physicians and patients alike.

OBJECTIVE

To investigate pathological and short-term outcomes since the most recent Gleason system modifications by the International Society of Urological Pathology (ISUP) in an attempt to divide the current Gleason grading system into prognostically accurate Gleason grade groups.

PATIENTS AND METHODS

We queried the Johns Hopkins Radical Prostatectomy Database (1982-2011), approved by the institutional review board, for men undergoing radical prostatectomy (RP) without a tertiary pattern since 2004 and identified 7869 men. Multivariable models were created using preoperative and postoperative variables; prognostic grade group (Gleason grade ≤ 6; 3 + 4; 4 + 3; 8; 9-10) was among the strongest predictors of biochemical recurrence-free (BFS) survival.

RESULTS

Significant differences were noted among the Gleason grade groups at biopsy; differences were noted in the race, PSA level, clinical stage, number of positive cores at biopsy and the maximum percentage of positive cores among the Gleason grade groups at RP. With a median (range) follow-up of 2 (1-7) years, 5-year BFS rates for men with Gleason grade ≤ 6, 3 + 4, 4 + 3, 8 and 9-10 tumours at biopsy were 94.6, 82.7, 65.1, 63.1 and 34.5%, respectively (P < 0.001 for trend); and 96.6, 88.1, 69.7, 63.7 and 34.5%, respectively (P < 0.001), based on RP pathology.

CONCLUSIONS

The 2005 ISUP modifications to the Gleason grading system for prostate carcinoma accurately categorize patients by pathological findings and short-term biochemical outcomes but, while retaining the essence of the Gleason system, there is a need for a change in its reporting to more closely reflect tumour behaviour. We propose reporting Gleason grades, including prognostic grade groups which accurately reflect prognosis as follows: Gleason score ≤ 6 (prognostic grade group I); Gleason score 3+4=7 (prognostic grade group II); Gleason score 4+3=7 (prognostic grade group III); Gleason score 4+4=8 (prognostic grade group (IV); and Gleason score 9-10 (prognostic grade group (V).

Multiple cores of Gleason score 6 correlate with favourable findings at radical prostatectomy

OBJECTIVE

To establish whether the good prognosis of Gleason score 6 (GS6) is maintained in the setting of multiple involved cores.

PATIENTS AND METHODS

In total, 6156 men (from 1 April 2000 to 30 April 2007) with GS6 on biopsy underwent radical prostatectomy (RP) at our institution. The number of positive cores was correlated with the outcome at RP.

RESULTS

More positive cores correlated with less organ-confined disease (P < 0.001), positive margins (P < 0.012), increasing RP grade (P < 0.001) and increased seminal vesicles/lymph node involvement (P = 0.012). For men with data available, the actuarial risk of being biochemically free of disease at 5 years was 93.2% when ≤6 cores were positive (812 men followed to 5 years) vs 89.1% if >6 cores were positive (41 men followed to 2 years) (P = 0.6). Although the predicted 'cure rate' of >75% probability of a tumour showing no evidence of biochemical recurrence at 10 years after RP was statistically different between cases with ≤6 vs >6 positive cores (P < 0.0001), the outcome in both groups was still favourable (90.5% vs 84%). Partin-like tables were generated factoring in the number of positive cores to predict organ-confined disease as a guide for urologists to perform nerve-sparing surgery. For example, with T1c disease, there was a ≥75% probability of organ-confined disease with one to three positive cores regardless of prostate-specific antigen (PSA) level, and the same probability was present with four to six positive cores and a PSA level of 0-4 ng/mL.

CONCLUSION

A low Gleason score on biopsy is a powerful prognostic finding, such that this favourable outcome is maintained even in the setting of multiple positive cores with GS6.