T2-Weighted MRI Radiomic Features Predict Prostate Cancer Presence and Eventual Biochemical Recurrence

Prostate cancer (PCa) is the most diagnosed non-cutaneous cancer in men. Despite therapies such as radical prostatectomy, which is considered curative, distant metastases may form, resulting in biochemical recurrence (BCR). This study used radiomic features calculated from multi-parametric magnetic resonance imaging (MP-MRI) to evaluate their ability to predict BCR and PCa presence. Data from a total of 279 patients, of which 46 experienced BCR, undergoing MP-MRI prior to surgery were assessed for this study. After surgery, the prostate was sectioned using patient-specific 3D-printed slicing jigs modeled using the T2-weighted imaging (T2WI). Sectioned tissue was stained, digitized, and annotated by a GU-fellowship trained pathologist for cancer presence. Digitized slides and annotations were co-registered to the T2WI and radiomic features were calculated across the whole prostate and cancerous lesions. A tree regression model was fitted to assess the ability of radiomic features to predict BCR, and a tree classification model was fitted with the same radiomic features to classify regions of cancer. We found that 10 radiomic features predicted eventual BCR with an AUC of 0.97 and classified cancer at an accuracy of 89.9%. This study showcases the application of a radiomic feature-based tool to screen for the presence of prostate cancer and assess patient prognosis, as determined by biochemical recurrence.

Outcomes of Grade Group 2 and 3 Prostate Cancer on Initial Versus Confirmatory Biopsy: Implications for Active Surveillance

BACKGROUND

Active surveillance (AS) is recommended as the preferred treatment for men with low-risk disease. In order to optimize risk stratification and exclude undiagnosed higher-grade disease, most AS protocols recommend a confirmatory biopsy.

OBJECTIVE

We aimed to compare outcomes among men with grade group (GG) 2/3 prostate cancer on initial biopsy with those among men whose disease was initially GG1 but was upgraded to GG2/3 on confirmatory biopsy.

DESIGN, SETTING, AND PARTICIPANTS

We reviewed patients undergoing radical prostatectomy (RP) in two cohorts: "immediate RP group," with GG2/3 cancer on diagnostic biopsy, and "AS group," with GG1 cancer on initial biopsy that was upgraded to GG2/3 on confirmatory biopsy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Probabilities of biochemical recurrence (BCR) and salvage therapy were determined using multivariable Cox regression models with risk adjustment. Risks of adverse pathology at RP were also compared using logistic regression.

RESULTS AND LIMITATIONS

The immediate RP group comprised 4009 patients and the AS group comprised 321 patients. The AS group had lower adjusted rates of adverse pathology (27% vs 35%, p = 0.003). BCR rates were lower in the AS group, although this did not reach conventional significance (hazard ratio [HR] 0.73, 95% confidence interval [CI] 0.50-1.06, p = 0.10) compared with the immediate RP group. Risk-adjusted 1- and 5-yr BCR rates were 4.6% (95% CI 3.0-6.5%) and 10.4% (95% CI 6.9-14%), respectively, for the AS group compared with 6.3% (95% CI 5.6-7.0%) and 20% (95% CI 19-22%), respectively, in the immediate RP group. A nonsignificant association was observed for salvage treatment-free survival favoring the AS group (HR 0.67, 95% CI 0.42, 1.06, p = 0.087).

CONCLUSIONS

We found that men with GG1 cancer who were upgraded on confirmatory biopsy tend to have less aggressive disease than men with the same grade found at initial biopsy. These results must be confirmed in larger series before recommendations can be made regarding a more conservative approach in men with upgraded pathology on surveillance biopsy.

PATIENT SUMMARY

We studied men with low-risk prostate cancer who were initially eligible for active surveillance but presented with more aggressive cancer on confirmatory biopsy. We found that outcomes for these men were better than the outcomes for those diagnosed initially with more serious cancer.

Development of a Prognostic Model of Overall Survival for Metastatic Hormone-Naïve Prostate Cancer in Japanese Men

Simple Summary

Treatment strategies have changed dramatically in recent years with the development of a variety of agents for metastatic hormone-naïve prostate cancer. There is a need to identify prognostic factors for the appropriate choice of treatment for patients with hormone-naïve prostate cancer in Japanese men. Among the prostate cancer patients receiving treatment at our institution from 2000 to 2019, 198 patients with bone or visceral metastases at the initial diagnosis were included in the study. We retrospectively examined these factors of the overall survival, and identified Gleason pattern 5 content, bone scan index ≥ 1.5, and lactate dehydrogenase evels ≥ 300 IU/L as prognostic factors. Using these three factors, we developed a new prognostic model for overall survival that can more objectively predict the prognosis of patients simply and objectively.

Abstract

Background: Treatment strategies have changed dramatically in recent years with the development of a variety of agents for metastatic hormone-naïve prostate cancer (mHNPC). There is a need to identify prognostic factors for the appropriate choice of treatment for patients with mHNPC, and we retrospectively examined these factors. Methods: Patients with mHNPC treated at our institution from 2000 to 2019 were included in this study. Overall survival (OS) was estimated retrospectively using the Kaplan–Meier method, and factors associated with OS were identified using univariate and multivariate analyses. A prognostic model was then developed based on the factors identified. Follow-up was terminated on 24 October 2021. Results: The median follow-up duration was 44.2 months, whereas the median OS was 85.2 months, with 88 patients succumbing to their disease. Multivariate analysis identified Gleason pattern (GP) 5 content, bone scan index (BSI) ≥ 1.5, and lactate dehydrogenase (LDH) levels ≥ 300 IU/L as prognostic factors associated with OS. We also developed a prognostic model that classified patients with mHNPC as low risk with no factor, intermediate risk with one factor, and high risk with two or three factors. Conclusions: Three prognostic factors for OS were identified in patients with mHNPC, namely GP5 inclusion, BSI ≥ 1.5, and LDH ≥ 300. Using these three factors, we developed a new prognostic model for OS that can more objectively predict patient prognosis.

MRI-detectability and histological factors of prostate cancer including intraductal carcinoma and cribriform pattern

BACKGROUND

Histopathological characteristics affecting the detectability of clinically significant prostate cancer (csPCa) on magnetic resonance imaging (MRI) remain unclear. This study aimed to compare the histopathology between MRI-detectable and MRI-undetectable cancers, emphasizing intraductal carcinoma of the prostate (IDC-P) and predominant Gleason pattern 4 subtype.

METHODS

This single-center retrospective study enrolled 153 consecutive patients with 191 lesions who underwent preoperative multiparametric MRI and subsequent radical prostatectomy. MRI/histopathological findings and area fractions of histological components (cancer cells, stroma, and luminal spaces) of MRI-detectable and MRI-undetectable cancers were compared. Data were analyzed using Fisher's exact, independent t, or Mann-Whitney U tests.

RESULTS

Overall, 148 (77%) and 43 (23%) cancers were MRI-detectable and MRI-undetectable, respectively. MRI-detectable cancers were significantly larger than MRI-undetectable cancers (p = 0.03). The percentage of lesions in Grade Group 3 or higher was significantly higher among MRI-detectable cancers than among MRI-undetectable cancers (p = 0.02). MRI detectability of csPCa was associated with increases in relative area fractions of cancer cells (p < 0.001) and decreases in those of stroma (p < 0.001) and luminal spaces (p < 0.001) in prostate cancer (PCa) than the percentage of Gleason pattern 4 (p = 0.09). The percentage of lesions containing IDC-P was similar for MRI-detectable and MRI-undetectable cancers (40% vs. 33%; p = 0.48). The distribution of cribriform gland subtypes was not significantly different between MRI-detectable and MRI-undetectable Gleason pattern 4 subtype cancers (p > 0.99). Contrarily, the ratio of fused gland subtype was significantly higher in MRI-detectable than in MRI-undetectable cancers (p = 0.03). Furthermore, the ratio of poorly-formed gland subtype was significantly higher in MRI-undetectable than in MRI-detectable cancers (p = 0.01).

CONCLUSIONS

MRI detectability of csPCa is strongly associated with the relative area fractions of cancer cells, stroma, and luminal spaces in PCa rather than conventional histopathological parameters. Neither the presence nor the percentage of IDC-P affected MRI detectability.

Prognostic Models for Patients With Gleason Score 9 Prostate Cancer: A Population-Based Study

Purpose: Gleason score (GS) system is one of the most widely used histological grading methods for prostate cancer (PCa) all over the world. GS can be obtained by adding the primary Gleason pattern (GP) and secondary GP. Different proportions of GP 4 and GP 5 in prostate specimens can both lead to GS 9. In this study, we explored whether GP 5 + 4 or GP 4 + 5 was associated with different prognoses among patients with GS 9 PCa.

Materials and methods: A retrospective population-based study was conducted on 10,124 subjects diagnosed with GS 9 PCa between 2004 and 2009 from the Surveillance, Epidemiology, and End Results program. A 1:1 propensity-score matching (PSM) was performed to balance the baseline characteristics between the GP 4 + 5 and 5 + 4 groups and to compare the prognoses between the two groups. Cox regression analysis and Fine-Gray competing risk regression models were adopted to screen the covariates significantly associated with all-cause mortality (ACM) and cancer-specific mortality (CAM).

Results: GP 5 + 4 was associated with higher risks of ACM and CSM before or after PSM than GP 4 + 5. In the original cohort, there were eight independent predictors for ACM, which were age at diagnosis, race, AJCC NM stage, PSA levels, treatments, GP, and marital status, confirmed by the Cox analysis; and nine independent predictors for CSM, which were age at diagnosis, race, AJCC TNM stage, PSA levels, treatments, GP, and marital status, confirmed by the competing-risk model.

Conclusion: GP 5 + 4 was associated with a poorer overall survival and cancer-specific survival compared with GP 4 + 5.

Gene expression analysis reveals a pitfall in the molecular research of prostate tumors relevant to Gleason score

Gleason score (GS) is a powerful prognostic factor in prostate cancer (PCa). A GS-7 tumor typically has the primary Gleason (architectural) pattern and secondary prevalent one being graded with 3 and 4 (or 4 and 3), respectively. Due to the well-known intratumoral multifocal occurrence of different patterns, a biological sample from a GS-7 tumor used in a molecular experiment will be uncertain regarding the actually represented pattern if no special attention is given to specimen preparation. In this study, by an integrative analysis of several published gene expression datasets, one of which is the profiling of the paired GP-3 (Gleason pattern 3) and GP-4 (Gleason pattern 4) specimens of 13 GS-7 tumors, we demonstrate that such an uncertainty can be frequently observed in the published data. More specifically, our results suggest that the GS-7 specimens used to generate the frequently-cited The Cancer Genome Atlas (TCGA) data and the Gene Expression Omnibus (GEO) dataset GSE21032 which largely are individual GP-3 or GP-4 specimens rather than the "intermediate" specimens of GP-3 and GP-4. This indicates a pitfall in the existing molecular research of prostate tumors relevant to GS and in GS-related molecular biomarker identification using the previously documented data.

Gleason pattern 4 with cribriform morphology on biopsy is associated with adverse clinicopathological findings in a prospective radical prostatectomy cohort

The prognostic significance of the Gleason grading system has been well established. However, individual Gleason patterns comprise heterogeneous morphologies which might add additional prognostic information. Recent evidence suggests that Gleason pattern 4 with cribriform growth pattern is associated with an adverse prognosis. To determine the association between cribriform pattern on biopsies and pathological findings on subsequent prostatectomies, we evaluated the presence of cribriform architecture in a prospective cohort of 367 men from 2014 to 2018 treated at a single institution. Cribriform architecture was present in 63.5% of all biopsies and was correlated with the overall extent of Gleason pattern 4. In addition, cribriform morphology on biopsy showed a statistically significant association with higher Gleason grade and increased pathological stage and nodal metastasis. In a subset analysis of cases with Grade Group 2 (Gleason score 3 + 4, n = 208), these associations did not reach statistical significance, but the presence of cribriform growth in this subgroup showed a trend toward increased upgrading to Grade Group 5 (Gleason score 9/10) (1 [0.5%] vs. 5 [2.4%], P = 0.06). This large prospective study comparing biopsy and prostatectomy finding of cribriform architecture demonstrates that cribriform pattern 4 is associated with adverse prognostic features and highlights the relevance for recognizing specific morphologies with distinct biological and clinical features.

The expression of MYC is strongly dependent on the circular PVT1 expression in pure Gleason pattern 4 of prostatic cancer

PVT1 is a long-noncoding RNA and is highly expressed in various cancers including prostate cancers with stabilizing MYC protein. To characterize the objective biological features of the different morphological components such as Gleason patterns (GP) in prostate cancer, biopsy specimens containing only single pure GP (GP3, GP4, GP5) are used to analyze the relationship between PVT1 expression and MYC protein expression. The expressions of PVT1 and MYC were analyzed by quantitative PCR and the labeling index (LI) of MYC protein by immunohistochemical staining. PVT1, MYC, and MYC protein were highly expressed in GP 4, and interestingly the expression between PVT1 and MYC LI significantly correlated only in GP 4. In vitro experiments, the expression of MYC protein was slightly reduced by small interfering RNA against PVT1, while strongly reduced against specifically circular PVT1, splicing variants derived from the PVT1. Taken together, the expression characteristics of PVT1, MYC, and MYC protein differed depending on the GP. In particular, circular PVT1 might be strongly involved in the stabilization of MYC protein in GP4 and suggest different biological features.

Predictive factors for short-term biochemical recurrence-free survival after robot-assisted laparoscopic radical prostatectomy in high-risk prostate cancer patients

BACKGROUND

We aimed to assess the short-term oncological outcomes of robot-assisted laparoscopic radical prostatectomy to determine the predictive factors associated with biochemical recurrence in high-risk prostate cancer patients.

METHODS

A total of 331 patients with localized prostate cancer underwent robot-assisted laparoscopic radical prostatectomy. Of them, 113 patients were diagnosed with high-risk prostate cancer according to the D'Amico risk group classification. We evaluated the association between pre- or postoperative predictive factors and biochemical recurrence using Cox regression analysis.

RESULTS

The 2-year biochemical recurrence-free survival rate was 65.0% in the high-risk group. On univariate analyses, PSA level > 20 ng/mL, Gleason pattern 5 component on biopsy, pathological stage T3 or higher, perineural invasion, and positive surgical margin were predictive factors for biochemical recurrence. On multivariate analysis, PSA level > 20 ng/mL, Gleason pattern 5 component on biopsy, perineural invasion, and positive surgical margin were identified as independent predictive factors. The 2-year biochemical recurrence-free survival rate was 36.5% for patients with PSA level > 20 ng/mL and/or Gleason pattern 5 component on biopsy.

CONCLUSIONS

PSA level > 20 ng/mL and/or presence of the Gleason pattern 5 component on biopsy are predictive factors for early biochemical recurrence after robot-assisted laparoscopic radical prostatectomy in high-risk prostate cancer patients. We considered that these patients require a combined modality therapy to improve their prognosis.

Grading of prostate cancer: a work in progress

Grading of prostate cancer has evolved substantially over time, not least because of major changes in diagnostic approach and concomitant shifts from late- to early-stage detection since the adoption of PSA testing from the late 1980s. After the conception of the architecture-based nine-tier Gleason grading system more than 50 years ago, several changes were made in order to increase its prognostic impact, to reduce interobserver variation and to improve concordance between prostate needle biopsy and radical prostatectomy grading. This eventually resulted in the current five-tier grading system, with a much more detailed description of the individual architectural patterns constituting the remaining three Gleason patterns (i.e. grades 3-5). Nevertheless, there is room for improvement. For instance, distinction of common grade 4 subpatterns such as ill-formed and fused glands from the grade 3 pattern is challenging, blurring the division between low-risk patients who could be eligible for deferred therapy and those who need curative therapy. The last few years have witnessed the publication of several studies on the prognostic impact of individual architectural subpatterns showing that, in particular, the cribriform pattern exceeded the prognostic impact of other grade 4 subpatterns. This review provides an overview of the changes in prostate cancer grading over time and provides a thorough description of the various Gleason subpatterns, the current evidence of their prognostic impact and areas of contention. Potential practical ways for improvements of the current grading system are also put forward.

Correlation with Gleason patterns 4 and 5 at prostate biopsy

Context:

The correlation between aggressive prostate cancer and obesity mainly based on body mass index (BMI) and pathology after surgery remains controversial.

Aims:

The aim of the study was to correlate BMI, visceral adiposity index (VAI), and the plasmatic levels of leptin, adiponectin, and matrix metalloproteinase-3 (MMP-3), and biomarkers of adipose tissue function, with the detection of Gleason patterns 4 and 5 at biopsy.

Subjects and Methods:

Consecutive patients with prostate cancer at 12-core transrectal biopsy were enrolled. BMI, waist circumference (WC), blood samples to evaluate the plasmatic levels of triglycerides (TG) and high-density lipoproteins (HDL), adiponectin, leptin, and MMP-3 were obtained immediately before biopsy. The VAI was calculated according to the formula: WC/(39.68 + [1.88 × BMI]) × TG/1.03 × 1.31/HDL.

Results:

One hundred and forty-nine patients were entered. The median PSA, BMI, and VAI were 10.0 ng/ml, 27.6 kg/m², and 4.6, respectively. Gleason patterns 4 or 5 were detected in 68 (45.6%) patients; in 15 (41.7%), 31 (44.9%), and 22 (50.0%) among normal weight, overweight, and obese patients, respectively (P = 0.55). The statistical analysis did not show any significant correlation between BMI, VAI, the plasmatic levels of leptin, adiponectin, MMP-3, and the detection of Gleason patterns 4 and 5 at biopsy. A statistically significant association emerged with older age (P = 0.017) and higher PSA values (P = 0.02).

Conclusion:

We did not find any association between BMI, VAI, the plasmatic levels of adiponectin, leptin, and MMP-3 and the detection of Gleason patterns 4 and 5 at prostate biopsy.

Evaluation of tumor morphologies and association with biochemical recurrence after radical prostatectomy in grade group 5 prostate cancer

We assessed Gleason pattern 5 (GP5) and other prostatic adenocarcinoma (PCa) morphologies to determine their association with biochemical recurrence (BCR). A search for grade group 5 PCa with radical prostatectomy (RP) yielded 49 patients. RPs were reviewed for %GP5 and morphologies (sheets, single cells, cords, small solid cylinders, solid medium to large nests with rosette-like spaces [SMLNRS], comedonecrosis, cribriform glands, glomerulations, intraductal carcinoma of the prostate [IDC-P], and prostatic ductal adenocarcinoma [PDCa]). Prevalence of morphologies was as follows: single cells 100%, cribriform glands 98.7%, cords 85.7%, IDC-P 77.6%, comedonecrosis 53.1%, sheets 49.0%, small solid cylinders 49.0%, PDCa 44.9%, glomerulations 34.7%, and SMLNRS 14.3%. From 28 patients who were treated with RP as monotherapy, 64.3% (18/28) had BCR. Comedonecrosis, sheets, small solid cylinders, IDC-P, and PDCa were significantly associated with BCR. Number of morphologies on RP and %GP5 were higher in patients with BCR (6.8 ± 2.1 versus 3.7 ± 2.9%; P < 0.001 and 26.9 ± 16.8 versus 11.4 ± 14.1%; P = 0.02) with area under ROC curve of 0.89 (confidence intervals [CI] 0.77-1.00). Sensitivity/specificity was 77.8/80.0% for predicting BCR when ≥ 5 morphologies were present and 0.79 (CI 0.60-0.99) with sensitivity/specificity of 66.7/80.0% for predicting BCR when ≥ 15% GP5 was present. Hazard ratio for BCR was higher with increasing number of morphologies (1.23, CI 1.02-1.49; P = 0.034) but not %GP5 (0.99, CI 0.97-1.02, P = 0.622). Our results indicate that GP5 morphologies may represent a biologically heterogeneous group and that an increasing number of PCa morphologies on RP is strongly associated with an increased risk of BCR.

Distinct DNA methylation alterations are associated with cribriform architecture and intraductal carcinoma in Gleason pattern 4 prostate tumors

The aim of the present study was to explore DNA methylation aberrations in association with cribriform architecture and intraductal carcinoma (IDC) of the prostate, as there is robust evidence that these morphological features are associated with aggressive disease and have significant clinical implications. Herein, the associations of a panel of seven known prognostic DNA methylation biomarkers with cribriform and IDC features were examined in a series of 91 Gleason pattern (GP) 4 tumors derived from Gleason score 7 radical prostatectomies. Gene specific DNA methylation was compared between cribriform and/or IDC positive vs. negative cases, and in association with clinicopathological features, using Chi square and Mann-Whitney U tests. DNA methylation of the adenomatous polyposis coli, Ras association domain family member 1 and T-box 15 genes was significantly elevated in GP4 tumors with cribriform and/or IDC features compared with negative cases (P=0.045, P=0.007 and P=0.013, respectively). To the best of our knowledge, this provides the first evidence for an association between cribriform and/or IDC and methylation biomarkers, and warrants further investigation of additional DNA methylation events in association with various architectural patterns in prostate cancer.

Diffusion-weighted endorectal MR imaging at 3T for prostate cancer: correlation with tumor cell density and percentage Gleason pattern on whole mount pathology

OBJECTIVE

To determine if tumor cell density and percentage of Gleason pattern within an outlined volumetric tumor region of interest (TROI) on whole-mount pathology (WMP) correlate with apparent diffusion coefficient (ADC) values on corresponding TROIs outlined on pre-operative MRI.

METHODS

Men with biopsy-proven prostate adenocarcinoma undergoing multiparametric MRI (mpMRI) prior to prostatectomy were consented to this prospective study. WMP and mpMRI images were viewed using 3D Slicer and each TROI from WMP was contoured on the high b-value ADC maps (b0, 1400). For each TROI outlined on WMP, TCD (tumor cell density) and the percentage of Gleason pattern 3, 4, and 5 were recorded. The ADC_mean, ADC_{10th percentile}, ADC_{90th percentile}, and ADC_ratio were also calculated in each case from the ADC maps using 3D Slicer.

RESULTS

Nineteen patients with 21 tumors were included in this study. ADC_mean values for TROIs were 944.8 ± 327.4 vs. 1329.9 ± 201.6 mm²/s for adjacent non-neoplastic prostate tissue (p < 0.001). ADC_mean, ADC_{10th percentile}, and ADC_ratio values for higher grade tumors were lower than those of lower grade tumors (mean 809.71 and 1176.34 mm²/s, p = 0.014; 10th percentile 613.83 and 1018.14 mm²/s, p = 0.009; ratio 0.60 and 0.94, p = 0.005). TCD and ADC_mean (ρ = -0.61, p = 0.005) and TCD and ADC_{10th percentile} (ρ = -0.56, p = 0.01) were negatively correlated. No correlation was observed between percentage of Gleason pattern and ADC values.

CONCLUSION

DWI MRI can characterize focal prostate cancer using ADC_ratio, ADC_{10th percentile}, and ADC_mean, which correlate with pathological tumor cell density.

Molecular characterization of Gleason patterns 3 and 4 prostate cancer using reverse Warburg effect-associated genes

Background

Gleason scores (GS) 3+3 and 3+4 prostate cancers (PCa) differ greatly in their clinical courses, with Gleason pattern (GP) 4 representing a major independent risk factor for cancer progression. However, Gleason grade is not reliably ascertained by diagnostic biopsy, largely due to sampling inadequacies, subjectivity in the Gleason grading procedure, and a lack of more objective biomarker assays to stratify prostate cancer aggressiveness. In most aggressive cancer types, the tumor microenvironment exhibits a reciprocal pro-tumorigenic metabolic phenotype consistent with the reverse Warburg effect (RWE). The RWE can be viewed as a physiologic response to the epithelial phenotype that is independent of both the epithelial genotype and of direct tumor sampling. We hypothesize that differential expression of RWE-associated genes can be used to classify Gleason pattern, distinguishing GP3 from GP4 PCa foci.

Methods

Gene expression profiling was conducted on RNA extracted from laser-capture microdissected stromal tissue surrounding 20 GP3 and 21 GP4 cancer foci from PCa patients with GS 3+3 and GS ≥4+3, respectively. Genes were probed using a 102-gene NanoString probe set targeted towards biological processes associated with the RWE. Differentially expressed genes were identified from normalized data by univariate analysis. A top-scoring pair (TSP) analysis was completed on raw gene expression values. Genes were analyzed for enriched Gene Ontology (GO) biological processes and protein-protein interactions using STRING and GeneMANIA.

Results

Univariate analysis identified nine genes (FOXO1 (AUC: 0.884), GPD2, SPARC, HK2, COL1A2, ALDOA, MCT4, NRF2, and ATG5) that were differentially expressed between GP3 and GP4 stroma (p<0.05). However, following correction for false discovery, only FOXO1 retained statistical significance at q<0.05. The TSP analysis identified a significant gene pair, namely ATG5/GLUT1. Greater expression of ATG5 relative to GLUT1 correctly classified 77.4 % of GP3/GP4 samples. Enrichment for GO-biological processes revealed that catabolic glucose processes and oxidative stress response pathways were strongly associated with GP3 foci but not GP4. FOXO1 was identified as being a primary nodal protein.

Conclusions

We report that RWE-associated genes can be used to distinguish between GP3 and GP4 prostate cancers. Moreover, we find that the RWE response is downregulated in the stroma surrounding GP4, possibly via modulation of FOXO1.

Electronic supplementary material

The online version of this article (doi:10.1186/s40170-016-0149-5) contains supplementary material, which is available to authorized users.

The association of the cribriform pattern with outcome for prostatic adenocarcinomas

With the revision of the Gleason system at the 2005 International Society of Urological Pathology Consensus Conference, there was consensus that most cribriform glands should be classified as pattern 4. There is now increased understanding that invasive cribriform carcinoma is a relatively aggressive disease. This study was based on 233 radical prostatectomy (RP) specimens collected at the Department of Pathology, Umraniye Education and Research Hospital, from 2006 to 2013. We assessed the cribriform foci associated with the more definitive patterns 3, 4, and 5 elsewhere on the RP specimens and evaluated the association of the presence of cribriform pattern (CP) with biochemical prostate-specific antigen recurrence (BPR). In Cox regression model, taking into account the Gleason score (GS), pathologic stage, surgical margin (SM) status, presence of a CP, and preoperative prostate-specific antigen (PSA), a positive SM, and the presence of a CP were independent predictors of BPR after RP. We observed BPR more frequently in GS 3+3 cases with a CP than in those without a CP (p=0.008). There was no significant difference in BPR status for cases with GS 3+4, 4+3, 4+5, and 5+4 when the patients were stratified by the presence of a CP. On the basis of these data, we suggest that the classification of CP into Gleason pattern 4 has value in predicting BPR status after RP. However, as many of these modifications are empirical and supported by only a few studies, long-term follow-up studies with clinical endpoints are necessary to validate these recommendations.

Gleason pattern 5 is the strongest pathologic predictor of recurrence, metastasis, and prostate cancer-specific death in patients receiving salvage radiation therapy following radical prostatectomy

BACKGROUND

The presence of Gleason pattern 5 (GP5) at radical prostatectomy (RP) has been associated with worse clinical outcome; however, this pathologic variable has not been assessed in patients receiving salvage radiation therapy (SRT) after a rising prostate-specific antigen level.

METHODS

A total of 575 patients who underwent primary RP for localized prostate cancer and subsequently received SRT at a tertiary medical institution were reviewed retrospectively. Primary outcomes of interest were biochemical failure (BF), distant metastasis (DM), and prostate cancer-specific mortality (PCSM), which were assessed via univariate analysis and Fine and Grays competing risks multivariate models.

RESULTS

On pathologic evaluation, 563 (98%) patients had a documented Gleason score (GS). The median follow-up post-SRT was 56.7 months. A total of 60 (10.7%) patients had primary, secondary, or tertiary GP5. On univariate analysis, the presence of GP5 was prognostic for BF (hazard ratio [HR] 3.3; P < .0001), DM (HR:11.1, P < .0001), and PCSM (HR:8.8, P < .0001). Restratification of the Gleason score to include GP5 as a distinct entity resulted in improved prognostic capability. Patients with GP5 had clinically worse outcomes than patients with GS8(4+4). On multivariate analysis, the presence of GP5 was the most adverse pathologic predictor of BF (HR 2.9; P < .0001), DM (HR 14.8; P < .0001), and PCSM (HR 5.7; P < .0001).

CONCLUSION

In the setting of SRT for prostate cancer, the presence of GP5 is a critical pathologic predictor of BF, DM, and PCSM. Traditional GS risk stratification fails to fully utilize the prognostic capabilities of individual Gleason patterns among men receiving SRT post-RP.