Incidence and outcomes of ductal carcinoma of the prostate in the USA: analysis of data from the Surveillance, Epidemiology, and End Results program

Nomogram for predicting the overall survival and cancer-specific survival of patients with intraductal carcinoma of the prostate

PURPOSE

Intraductal carcinoma of the prostate (IDC-P) is a histological subtype that differs from conventional acinar adenocarcinoma in terms of its origin, appearance, and pathological features. For IDC-P, there is currently no recognized best course of action, and its prognosis is unclear. The goal of this study is to analyze independent prognostic factors in IDC-P patients and to develop and validate a nomogram to predict overall survival (OS) and cancer-specific survival (CSS).

METHODS

Clinical data for IDC-P patients were collected from the Surveillance, Epidemiology, and End Results database. To identify the independent variables influencing prognosis, multivariate Cox regression analysis was performed. A nomogram model was created utilizing these variables after comparing the variations in OS and CSS among various subgroups using Kaplan‒Meier curves. Internal validation of the nomograms was verified using the bootstrap resampling method.

RESULTS

The study included 280 IDC-P patients in total. Marital status, summary stage, grade, and the presence of lung metastases were significant factors impacting OS, and CSS was significantly influenced by marital status, summary stage, AJCC stage, the presence of lung metastases, the presence of bone metastases, and PSA according to univariate and multivariate Cox regression models (P < 0.05). Nomogram models were created to estimate OS and CSS using these parameters. The OS prediction model's C-index was 0.744, whereas the CSS prediction model's C-index was 0.831.

CONCLUSION

We developed and verified nomogram models for the prediction of 1-, 3-, and 5-year OS and CSS in patients with IDC-P. These nomograms serve as a resource for evaluating patient prognosis, therapy, and diagnosis, ultimately improving clinical decision-making accuracy.

Construction and validation of a prognostic nomogram for ductal adenocarcinoma of the prostate: A population-based study

This study aimed to establish and validate a nomogram for ductal adenocarcinoma of the prostate (DAC) to accurately predict the prognosis of DAC patients. The data of 834 patients with confirmed DAC were obtained from the Surveillance, Epidemiology, and End Results database. The cases were randomly assigned to the training and internal validation cohorts. Data from patients attending our institution as an external validation cohort (n = 35). Nomogram and web-based dynamic nomogram were constructed based on Cox regression analysis, and their prediction accuracy was evaluated by concordance index (C-index), calibration curve, receiver operating characteristic (ROC) curve, and decision curve analysis. Multivariate analyses identified age, T-stage, N-stage, M-stage, surgery, lymph node dissection, Gleason score, and PSA as independent prognostic factors for overall survival. The C-index and calibration curves demonstrate the good discriminative performance of the prediction model. The area under the curve further confirmed the accuracy of the nomogram in predicting survival. In addition, the area under the curve and decision curve analysis were better than the 7th tumor-node-metastasis staging system. The Kaplan-Meier curves of the nomogram-based risk groups showed significant differences (P < .001). We constructed and validated the first nomogram to predict patients with DAC.

Radiotherapy for ductal carcinoma of the prostate: an analysis based on the Japanese radiation oncology study group survey

BACKGROUND

The clinical characteristics of prostate ductal carcinoma is still unclear, and treatment strategy has not yet been established due to its rarity. Therefore, we conducted a multicenter survey of radiation therapy for prostate ductal carcinoma in Japan.

METHOD

Data of patients with ductal carcinoma of the prostate treated with radiation therapy between 1996 and 2018 were extracted from the database of each facility.

RESULTS

Fifty-two treatment records of 41 patients were collected from nine institutions. The treatment purpose and situations were varied curative intent to palliation. Twenty-eight patients received curative treatments. The median follow-up period of these patients was 68 months. Androgen deprivation therapy was combined with radiation therapy in 26 cases (93%). X-ray and particle irradiation was used. Radiation dose range was 63-78 Gy; 5-year overall survival, progression-free survival and biochemical relapse-free survival were 87.0, 79.3 and 79.3%, respectively. One patient experienced Grade 3 radiation proctitis and one experienced Grade 3 radiation cystitis. There were no Grade 4 or worse adverse events.

CONCLUSION

Most patient received similar treatment with adenocarcinoma of prostate, and the clinical results were compatible. For more reliable evidence, further studies are required.

Genomic analysis of aggressive ductal adenocarcinoma of the prostate

BACKGROUND

Genomic profile analysis using next-generation sequencing can potentially elucidate the pathogenesis of rare cancers. Ductal adenocarcinoma, a rare subtype of prostate cancer, has an aggressive nature. This is the first study to analyze the genomic profile of ductal adenocarcinoma in an Asian population.

METHODS

We identified 12 patients newly diagnosed with ductal adenocarcinoma of the prostate at two hospitals, and nine patients (75.0%) had the pure type. Genomic assessment was performed using either the PleSSision testing platform or FoundationOne CDx.

RESULTS

At least one genomic alteration occurred in 11 patients (91.7%), and the most frequently mutated gene was tumor suppressor protein p53 (TP53), which was found in six cases (50.0%). Alterations characteristic of this cohort were found in four cases (33.3%) of retinoblastoma transcriptional corepressor 1 (RB1), which was only observed in the pure type. Compared to previous study results, the frequency of genetic alterations in the phosphoinositide 3-kinase (PI3K) pathway (n = 3; 25.0%) and Wnt-β-catenin pathway (n = 5; 41.7%) was comparable, but no alterations in the DNA damage repair (DDR) pathway were observed. None of the patients presented high tumor mutation burden or microsatellite instability.

CONCLUSIONS

We found that the Asian cohort with ductal adenocarcinoma had actionable alterations, and a high frequency of alterations in TP53 and RB1 reflected the aggressive nature of the tumor. Genetic analysis using next-generation sequencing is expected to help elucidate the pathogenesis of ductal adenocarcinoma.

Ductal prostate cancer: Clinical features and outcomes from a multicenter retrospective analysis and overview of the current literature

Objective

The aim of the study is to evaluate clinical features and outcomes after different therapeutic strategies for ductal prostate adenocarcinoma (DPC), a rare but aggressive subtype of invasive prostate cancer (PCa) accounting for, in the pure and mixed form, 1% or less and 5% or less, respectively, of all the newly diagnosed PCa.

Materials and methods

Patients with a proven diagnosis of DPC undergoing surgery, radiotherapy, and androgen deprivation therapy, alone or in combination, were considered for this multicenter, retrospective study. The study assessed overall survival (OS), disease-free survival (DFS), and age-related disease-specific survival.

Results

Eighty-one patients met the study inclusion criteria. Pure DPC was found in 29 patients (36%) and mixed ductal-acinar-PCa in 52 patients (64%). After a median follow-up of 63 months (range, 3-206 months), 3- and 5-year OS rates were 84% and 67%, respectively, and 3- and 5-year DFS rates were 54% and 34%, respectively. There were no significant differences in OS or DFS between the pure and mixed DPC groups. Pure DPC was associated with a higher rate of metastatic disease at onset. Patients 74 years or younger had better disease-specific survival (p=0.0019). A subgroup analysis favored radiotherapy as the primary treatment for nonmetastatic, organ-confined DPC (3- and 5-year DFS of 80% and 50%, respectively, compared with 5-year DFS of 35% for surgical patients; p = 0.023).

Conclusions

Our study found DPC to be rarer, more aggressive, more likely to metastasize, and have a worse prognosis than the common acinar variant, especially in its pure form. Multicenter series are encouraged to obtain large data sets, or propensity score matching analyses with patients with conventional PCa are desirable to understand the best therapeutic approach and improve outcomes.

Comparison of Survival Outcomes and Risk Factors Between Ductal Carcinoma of the Prostate and Acinar Adenocarcinoma of the Prostate: A Population-based Propensity Score-matching Study

Background

Ductal carcinoma of the prostate (DCP) is a rare type of prostate cancer (PCa) with a higher degree of infiltration and worse prognosis than acinar adenocarcinoma of the prostate (ACP). Previous reports comparing DCP and ACP have not been very reliable and involved small sample sizes.

Objective

To assess differences in mortality between ACP and DCP in a large-scale study.

Design setting and participants

Data were downloaded from the Surveillance, Epidemiology, and End Results database in June 2022. Data for 823 939 patients diagnosed with PCa from 2004 to 2019 were examined, excluding cases with survival data missing or pathological types other than DCP and ACP.

Outcome measurements and statistical analysis

Prognostic and risk factors for DCP were analyzed by generating a propensity score-matched cohort of DCP and ACP cases (1:5). Adjusted Cox models were constructed to determine hazard ratios (HRs) with 95% confidence intervals (CIs) for cancer-specific mortality (CSM) and overall mortality (OM).

Results and limitations

A total of 822 607 cases (99.8%) has ACP and 1332 (0.2%) had DCP. In comparison to ACP, age at diagnosis was significantly lower for DCP (≤66 yr: 38.0% vs 50.7%; p < 0.001) and a higher proportion of DCP patients distant metastases (13.7% vs 5.1%; p < 0.001). In comparison to the ACP group, significantly higher proportions of the DCP group underwent surgery (66.1% vs 38.1%; p < 0.001), radiotherapy (13.7% vs 3.1%; p < 0.001), or systemic therapy (18.2% vs 3.3%; p < 0.001). However, the median overall survival time was significantly shorter for DCP patients (44.0 vs 73.0 mo; p < 0.001). DCP patients also had higher risk of CSM (HR 2.07, 95% CI 1.68-2.56; p < 0.001) and OM (HR 2.73 95% CI 2.42-3.08; p < 0.001) after propensity score matching to adjust for the influence of baseline variables. Subgroup analysis showed that DCP patients who had surgical treatment had better CSM than those without surgery, while DCP patients with regional and lower stage had better OM than those with distant stage (both p < 0.05 for interaction).

Conclusions

The risk of CSM and OM is significantly higher for DCP than for ACP. Earlier detection (lower stage) and surgical treatment are beneficial factors for DCP prognosis.

Patient summary

We studied survival rates for two different types of prostate cancer. We found that survival is worse for the rarer ductal carcinoma of the prostate (DCP) than for the more common acinar adenocarcinoma of the prostate. Both early diagnosis when the cancer is at a lower stage and surgical treatment are beneficial for survival in patients with DCP.

Case report: Recurrent urethral polyps, an atypical presentation of ductal prostate adenocarcinoma

Prostate ductal adenocarcinoma is a rare subtype of prostate adenocarcinoma which can show aggressive features and have poor response to conventional treatment. Early diagnosis aids in shared patient decision making. We report an atypical presentation of this rare condition where a recurrent urethral polyp which showed pagetoid spread was diagnosed as ductal adenocarcinoma of the prostate, with emphasis on review of prior available histology.

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Consider ductal prostate carcinoma if observing pagetoid spread down urethra.

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Consider as differential diagnosis for recurrent prostatic urethral polyps.

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If recurrent presentations especially if presence of atypia review original histology.

Magnetic resonance imaging findings of pure prostatic ductal adenocarcinomas: a case series

PURPOSE

This study aimed to investigate the characteristics of magnetic resonance imaging (MRI) findings in pure prostatic ductal adenocarcinoma.

METHODS

From January 2009 to February 2020, seven patients who were diagnosed with pure prostatic ductal adenocarcinoma and had a referable preoperative MRI scan were included in the study. We evaluated the following MRI findings for each tumor: size, location, presence of multi-cystic component, and apparent diffusion coefficient (ADC) value.

RESULTS

The median maximum diameter of the tumors was 22 mm (range 19-70 mm). Regarding transverse distribution, five tumors were located in the periurethral area and two were located peripherally apart from the urethra. Two of the seven tumors had cystic components. The median ADC value of the tumors was 0.754 × 10^-3 mm²/s (range 0.570-0.963 × 10^-3 mm²/s). Based on the transverse distribution and components of the tumors on MRI, ductal adenocarcinomas were classified into three types: type I as a non-cystic tumor located peripherally apart from the urethra (29%, two cases); type II as a non-cystic tumor located in the periurethral area (43%, three cases); and type III as a tumor with a multi-cystic component (29%, two cases).

CONCLUSION

The non-cystic mass with periurethral distribution (type II) and multi-cystic mass (type III) may be characteristic features that differentiate pure ductal adenocarcinoma from ordinary acinar adenocarcinoma on MRI.

Intraductal Adenocarcinoma of the Prostate With Cribriform or Papillary Ductal Morphology: Rare Biopsy Cases Lacking Associated Invasive High-grade Carcinoma

Prostatic duct adenocarcinoma, characterized by pseudostratified columnar epithelium, has historically been considered invasive carcinoma, although it may commonly have an intraductal component. Usual (acinar) intraductal carcinoma of the prostate (IDC-P) is a noninvasive high-risk lesion typically associated with high-grade, high-stage prostate cancer. Whereas there have been rare biopsy studies of pure acinar IDC-P or IDC-P associated with only low-grade carcinoma, there have been no analogous series of IDC-P with cribriform or papillary ductal morphology on biopsy unassociated with invasive high-grade carcinoma. We identified 14 patients with biopsies showing IDC-P with ductal morphology, defined as prostatic duct adenocarcinoma confined to glands/ducts with immunohistochemically proven retention of basal cells. Our series includes 12 patients with pure IDC-P and 2 patients with concurrent low-volume Grade Group 1 invasive cancer in unassociated cores. Three patients underwent radical prostatectomy: 2/3 had high-grade cancer in their resection specimen (Grade Group 3, Grade Group 5), including 1 with advanced stage and nodal metastases; 1/3 had Grade Group 1 organ-confined carcinoma and spatially distinct IDC-P with ductal morphology. Five men had only follow-up biopsies: 2/5 had cancer (Grade Group 2, Grade Group 4); 1/5 had IDC-P (on 2 repeat biopsies); and 2/5 had benign transurethral resection of the prostate. In all 5 cases with invasive cancer, the invasive portion was comprised purely of acinar morphology; no invasive ductal component was identified. Five patients did not have follow-up biopsies and were treated with radiation therapy±androgen deprivation. One patient had no follow-up information. In an analogous situation to acinar IDC-P, we propose that rarely there is a precursor form of ductal adenocarcinoma that can exist without concurrent invasive high-grade carcinoma and propose the term "IDC-P with ductal morphology," consistent with the terminology for acinar prostate adenocarcinoma. Until more evidence is accumulated, we recommend reporting and treating patients with IDC-P with ductal morphology in a manner analogous to those with acinar IDC-P. As with pure IDC-P with acinar morphology, we would also recommend not grading pure IDC-P with ductal morphology. Finally, we propose a new addition to the diagnostic criteria of IDC-P to include intraductal lesions with ductal morphology consisting of papillary fronds or cribriform lesions lined by cytologically atypical pseudostratified epithelium.

Vasohibin-1 expression as a biomarker of aggressive nature in ductal adenocarcinoma of the prostate: a retrospective cohort study at two centres in Japan

OBJECTIVES

Vasohibin-1 (VASH1) is an endogenous angiogenesis regulator expressed in activated vascular endothelial cells. We previously reported that high VASH1 expression is a predictor of progression in acinar adenocarcinoma of the prostate. In this study, we evaluated the characteristics of ductal adenocarcinoma of the prostate by comparing the level of VASH1 expression between ductal and acinar adenocarcinoma specimens.

DESIGN AND SETTING

A retrospective cohort study at two centres in Japan.

PARTICIPANTS

Among the 1495 patients who underwent radical prostatectomy or transurethral resection for the past 15 years, a total of 14 patients diagnosed with ductal adenocarcinoma and 20 patients diagnosed with acinar adenocarcinoma with a Gleason score of 4+4 were included.

INTERVENTIONS

We immunohistochemically examined the CD34 expression as the microvessel density (MVD) and activated endothelial cells as the VASH1 density (vessels per mm²).

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was the association of MVD and VASH1 density between ductal and acinar adenocarcinoma, and the secondary outcome was their oncological outcomes.

RESULTS

Nine patients (64.3%) with ductal adenocarcinoma were diagnosed at an advanced clinical stage, and five patients (35.7%) died from cancer during a median follow-up of 56.0 months. The VASH1 densities (mean±SD) in ductal and acinar adenocarcinoma were 45.1±18.5 vs 16.1±21.0 (p<0.001), respectively, while the MVD (mean±SD) in ductal and acinar adenocarcinoma were 65.3±21.9 vs 80.8±60.7 (p=0.666), respectively. The 5-year cancer-specific survival rates for high and low VASH1 expression were 70.0% and 100.0% (p=0.006), respectively. High VASH1 expression and a diagnosis of ductal adenocarcinoma were significant predictors of cancer-specific survival.

CONCLUSIONS

Ductal adenocarcinoma was more aggressive and had higher VASH1 expression than acinar adenocarcinoma, although MVD was equivalent. These results indicate that VASH1 expression may serve as a novel biomarker for the aggressive nature of ductal adenocarcinoma.

Prostatic Ductal Adenocarcinoma Controlled for Tumor Grade, Stage, and Margin Status Does Not Independently Influence the Likelihood of Biochemical Recurrence in Localized Prostate Cancer After Radical Prostatectomy

CONTEXT.—

Prostatic ductal adenocarcinoma (PDA) has historically been considered to be an aggressive subtype of prostate cancer.

OBJECTIVE.—

To investigate if PDA is independently associated with worse biochemical recurrence (BCR)-free survival after radical prostatectomy.

DESIGN.—

A review of 1584 radical prostatectomies was performed to grade, stage, and assess margin status in each tumor nodule. Radical prostatectomies with localized PDA (ie, those lacking metastasis) in the tumor nodule with the highest grade and stage and worst margin status were matched with prostatic acinar adenocarcinoma according to grade, stage, and margin status. The effect of PDA on BCR was assessed by multivariable Cox regression and Kaplan-Meier analyses.

RESULTS.—

Prostatic ductal adenocarcinoma was present in 171 cases. We excluded 24 cases because of lymph node metastasis (n = 13), PDA not in the highest-grade tumor nodule (n = 9), and positive surgical margin in a lower-grade tumor nodule (n = 2). The remaining 147 cases included 26 Grade Group (GG) 2, 44 GG3, 6 GG4, and 71 GG5 cancers. Seventy-six cases had extraprostatic extension, 33 had seminal vesicle invasion, and 65 had positive margins. Follow-up was available for 113 PDA and 109 prostatic acinar adenocarcinoma cases. Prostate-specific antigen density (odds ratio, 3.7; P = .001), cancer grade (odds ratio, 3.3-4.3; P = .02), positive surgical margin (odds ratio, 1.7; P = .02), and tumor volume (odds ratio, 1.3; P = .02) were associated with BCR in multivariable analysis. Prostatic ductal adenocarcinoma, its percentage, intraductal carcinoma, and cribriform Gleason pattern 4 were not significant independent predictors of BCR.

CONCLUSIONS.—

Advanced locoregional stage, higher tumor grade, and positive surgical margin status rather than the mere presence of PDA are more predictive of worse BCR-free survival outcomes following radical prostatectomy in men with a component of PDA.

[Localized prostate cancer]

Prostate cancer is the most prevalent noncutaneous cancer in men. The Gleason grading is considered to be the strongest prognostic parameter regarding progression-free survival and overall survival. The original grading system has been modified during the last decade resulting in a more precise prognostic tool. The pretreatment Gleason score guides clinical management and is a key component in S3 guidelines for prostate cancer. In addition to Gleason score several other histologic findings in prostate needle biopsy influence patient management. In this second part of our CME series about prostate cancer, we will discuss the diagnosis of prostate cancer and current guidelines for reporting prostate cancer. In addition, we will highlight prostate lesions of urothelial origin and neuroendocrine prostate cancer as well as prognostic biomarkers.

A first case of ductal adenocarcinoma of the prostate having characteristics of neuroendocrine phenotype with PTEN, RB1 and TP53 alterations

BACKGROUND

Ductal adenocarcinoma and neuroendocrine cancer are rare subtypes of prostate cancer with poor prognosis and limited therapeutic options. We present the first case of ductal adenocarcinoma having a neuroendocrine phenotype.

CASE PRESENTATION

A 63-year-old man presented with gross hematuria and urinary retention, and his serum prostate-specific antigen level was 4.58 ng/mL. We performed transurethral resection of the prostate, and the diagnosis was ductal adenocarcinoma with a Gleason score of 5 + 4 for acinar adenocarcinoma. Magnetic resonance imaging showed local invasion of left lobe of the prostate and bone metastasis of the left trochanteric section of the femur. Multidisciplinary treatments such as androgen deprivation therapy, chemoradiation therapy, and surgery for metastatic lesions have led to long-term survival. Since next-generation sequencing revealed PTEN and RB1 co-loss and TP53 mutations, we re-evaluated the immunohistochemistry and he was found to be positive for synaptophysin.

CONCLUSIONS

This is the first Japanese case of ductal adenocarcinoma with a neuroendocrine phenotype. Genetic analysis may help not only guide the therapeutic strategies, but also sometimes with the diagnosis.

Knowing what's growing: Why ductal and intraductal prostate cancer matter

Prostate cancer is a common malignancy, but only some tumors are lethal. Accurately identifying these tumors will improve clinical practice and instruct research. Aggressive cancers often have distinctive pathologies, including intraductal carcinoma of the prostate (IDC-P) and ductal adenocarcinoma. Here, we review the importance of these pathologies because they are often overlooked, especially in genomics and preclinical testing. Pathology, genomics, and patient-derived models show that IDC-P and ductal adenocarcinoma accompany multiple markers of poor prognosis. Consequently, "knowing what is growing" will help translate preclinical research to pinpoint and treat high-risk prostate cancer in the clinic.

Oncological outcomes of patients with ductal adenocarcinoma of the prostate receiving radical prostatectomy or radiotherapy

Objective

To evaluate the oncological outcomes of ductal adenocarcinoma of the prostate (DAC) managed with radical prostatectomy (RP) or radiotherapy (RT) and optimize the proper treatment modality to DAC comprehensively.

Methods

The cohorts included a total of 528 patients from the Surveillance, Epidemiology and End Results (SEER) database, 354 receiving RP and 174 receiving RT. Cox proportional hazards regressions were performed to assess cancer specific mortality (CSM) and overall mortality (OM) between treatment groups. A competing risk analysis was further conducted. Subgroup analyses by age and level of prostate-specific antigen (PSA) were performed. Propensity score matching was implemented.

Results

Patients managed with RP had lower risks of CSM and OM compared with RT (before matching: Hazard ratio [HR]=0.24, 95% confidence interval [CI] 0.13–0.47 and HR=0.26, 95% CI 0.17–0.40, respectively; after matching: HR=0.18, 95% CI 0.04–0.82 and HR=0.28, 95% CI 0.11–0.70, accordingly). Subgroup analyses demonstrated that patients in the middle tertile of the age or with lower tertile PSA level managed with RP took lower risks of OM significantly (HR=0.18, 95% CI 0.06–0.57, p<0.01 and HR=0.17, 95% CI 0.06–0.54, p<0.01).

Conclusion

Among patients with DAC, treatment with RP was associated with better survival outcomes in comparison with RT. Patients with DAC in the middle tertile of the age and with lower tertile PSA level benefited the most from RP.

First case of ductal adenocarcinoma of the prostate with MAP3K1 homozygous deletion

INTRODUCTION

Ductal adenocarcinoma of the prostate is a rare prostate cancer variant and associated with higher stage and greater risk of mortality. Optimal systemic therapy for metastatic ductal adenocarcinoma is not known.

CASE PRESENTATION

A 67-year-old man presented with ductal adenocarcinoma of the prostate accompanied by multiple lung metastases and advanced bone metastases. We performed channel transurethral resection of the prostate and confirmed the diagnosis of ductal adenocarcinoma of the prostate. DNA sequencing identified a TP53 somatic point mutation (p.Gly245Ser) as the pathogenic variant. Furthermore, a homozygous deletion was observed in mitogen-activated protein kinase kinase kinase 1. The patient received enzalutamide but deceased 5 months after presenting to our institution.

CONCLUSION

To our knowledge, this is the first report of ductal adenocarcinoma of the prostate with a mitogen-activated protein kinase kinase kinase 1 homozygous deletion. Accumulation of whole-exome sequencing data is expected to inform future advances in therapy development.

Ductal variant prostate carcinoma is associated with a significantly shorter metastasis-free survival

BACKGROUND

Ductal adenocarcinoma is an uncommon prostate cancer variant. Previous studies suggest that ductal variant histology may be associated with worse clinical outcomes, but these are difficult to interpret. To address this, we performed an international, multi-institutional study to describe the characteristics of ductal adenocarcinoma, particularly focussing on the effect of presence of ductal variant cancer on metastasis-free survival.

METHODS

Patients with ductal variant histology from two institutional databases who underwent radical prostatectomies were identified and compared with an independent acinar adenocarcinoma cohort. After propensity score matching, the effect of the presence of ductal adenocarcinoma on time to biochemical recurrence, initiation of salvage therapy and the development of metastatic disease was determined. Deep whole-exome sequencing was performed for selected cases (n = 8).

RESULTS

A total of 202 ductal adenocarcinoma and 2037 acinar adenocarcinoma cases were analysed. Survival analysis after matching demonstrated that patients with ductal variant histology had shorter salvage-free survival (8.1 versus 22.0 months, p = 0.03) and metastasis-free survival (6.7 versus 78.6 months, p < 0.0001). Ductal variant histology was consistently associated with RB1 loss, as well as copy number gains in TAP1, SLC4A2 and EHHADH.

CONCLUSIONS

The presence of any ductal variant adenocarcinoma at the time of prostatectomy portends a worse clinical outcome than pure acinar cancers, with significantly shorter times to initiation of salvage therapies and the onset of metastatic disease. These features appear to be driven by uncoupling of chromosomal duplication from cell division, resulting in widespread copy number aberration with specific gain of genes implicated in treatment resistance.

Optimizing the diagnosis and management of ductal prostate cancer

Ductal adenocarcinoma (DAC) is the most common variant histological subtype of prostate carcinoma and has an aggressive clinical course. DAC is usually characterized and treated as high-risk prostatic acinar adenocarcinoma (PAC). However, DAC has a different biology to that of acinar disease, which often poses a challenge for both diagnosis and management. DAC can be difficult to identify using conventional diagnostic modalities such as serum PSA levels and multiparametric MRI, and the optimal management for localized DAC is unknown owing to the rarity of the disease. Following definitive therapy for localized disease with radical prostatectomy or radiotherapy, the majority of DACs recur with visceral metastases at low PSA levels. Various systemic therapies that have been shown to be effective in high-risk PAC have limited use in treating DAC. Although current understanding of the biology of DAC is limited, genomic analyses have provided insights into the pathology behind its aggressive behaviour and potential future therapeutic targets.

Prostatic ductal adenocarcinoma variant predicts worse pathological and oncological outcomes: Insight from over 1000 consecutive patients from a large prospective uro-oncology registry

OBJECTIVE

To evaluate if prostatic ductal adenocarcinoma (PDA) independently predicts poorer pathological and oncological outcomes after radical prostatectomy (RP).

METHODS AND MATERIALS

Utilizing a large prospective uro-oncology registry, clinicopathological parameters of 1027 consecutive patients who underwent RP (2008-2017) were recorded. Oncological outcomes were determined by failure to achieve unrecordable PSA postoperatively and biochemical failure (BCF).

RESULTS

PDA was present in 79 (7.7%) patients, whereas 948 (92.3%) patients had conventional prostatic acinar adenocarcinoma (PAA). Patients with PDA were older (mean 64.4 vs. 62.8-years old; p = .045), had higher PSA at diagnosis (mean 12.53 vs. 10.80 ng/ml; p = .034), and a higher percentage of positive biopsy cores (mean 39.34 vs. 30.53%; p = .006). Compared to PAA, PDA exhibited a more aggressive tumor biology: (1) Grade groups 4 or 5 (26.6 vs. 9.4%, p < .001), (2) tumor multifocality (89.9 vs. 83.6%; p = .049), and (3) tumor size (mean 2.97 vs. 2.00 cm; p < .001). On multivariate analysis, PDA was independently associated with locally advanced disease (p = .002, hazard ratio [HR]: 2.786, 95% confidence interval [CI]: 1.473-5.263), with a trend towards positive surgical margins (p = .055) and nodal involvement (p = .061). Translating the poorer pathological features to oncological outcomes, presence of PDA independently predicted less likelihood of achieving unrecordable PSA (p = .019, HR: 2.368, 95% CI: 1.152-4.868, and higher BCF (p = .028, HR: 1.918, 95% CI: 1.074-3.423). Subgroup analysis demonstrated that a higher ductal component greater than 15% proportionally predicted worse oncological outcomes, with a shorter time to BCF of 14.3 months compared to 19.8 months in patients with ductal component lesser than 15% (p = .040, HR: 2.660, 95% CI: 1.046-6.757).

CONCLUSION

PDA is independently associated with adverse pathological and oncological outcomes after RP. A higher proportion of PDA supports a higher BCF rate with a shorter time interval. An aggressive extirpative approach with close monitoring of postoperative serum PSA levels is warranted for these patients.

Ductal adenocarcinoma of the prostate: A systematic review and meta-analysis of incidence, presentation, prognosis, and management

Context

Ductal adenocarcinoma (DAC) is relatively rare, but is nonetheless the second most common subtype of prostate cancer. First described in 1967, opinion is still divided regarding its biology, prognosis, and outcome.

Objectives

To systematically interrogate the literature to clarify the epidemiology, diagnosis, management, progression, and survival statistics of DAC.

Materials and methods

We conducted a literature search of five medical databases from inception to May 04 2020 according to PRISMA criteria using search terms "prostate ductal adenocarcinoma" OR "endometriod adenocarcinoma of prostate" and variations of each.

Results

Some 114 studies were eligible for inclusion, presenting 2 907 170 prostate cancer cases, of which 5911 were DAC. [Correction added on 16 January 2021 after the first online publication: the preceding statement has been corrected in this current version.] DAC accounts for 0.17% of prostate cancer on meta-analysis (range 0.0837%-13.4%). The majority of DAC cases were admixed with predominant acinar adenocarcinoma (AAC). Median Prostate Specific Antigen at diagnosis ranged from 4.2 to 9.6 ng/mL in the case series.DAC was more likely to present as T3 (RR1.71; 95%CI 1.53-1.91) and T4 (RR7.56; 95%CI 5.19-11.01) stages, with far higher likelihood of metastatic disease (RR4.62; 95%CI 3.84-5.56; all P-values < .0001), compared to AAC. Common first treatments included surgery (radical prostatectomy (RP) or cystoprostatectomy for select cases) or radiotherapy (RT) for localized disease, and hormonal or chemo-therapy for metastatic disease. Few studies compared RP and RT modalities, and those that did present mixed findings, although cancer-specific survival rates seem worse after RP.Biochemical recurrence rates were increased with DAC compared to AAC. Additionally, DAC metastasized to unusual sites, including penile and peritoneal metastases. Where compared, all studies reported worse survival for DAC compared to AAC.

Conclusion

When drawing conclusions about DAC it is important to note the heterogenous nature of the data. DAC is often diagnosed incidentally post-treatment, perhaps due to lack of a single, universally applied histopathological definition. As such, DAC is likely underreported in clinical practice and the literature. Poorer prognosis and outcomes for DAC compared to AAC merit further research into genetic composition, evolution, diagnosis, and treatment of this surprisingly common prostate cancer sub-type.

Patient summary

Ductal prostate cancer is a rare but important form of prostate cancer. This review demonstrates that it tends to be more serious at detection and more likely to spread to unusual parts of the body. Overall survival is worse with this type of prostate cancer and urologists need to be aware of the presence of ductal prostate cancer to alter management decisions and follow-up.

Impact of treatment modality on overall survival in localized ductal prostate adenocarcinoma: A national cancer database analysis

PURPOSE

Ductal adenocarcinoma is considered a rare histological variant of prostate adenocarcinoma (PCa). Given the rarity of this subtype, optimal treatment strategies for men with nonmetastatic ductal PCa is largely unknown. We aimed to describe the impact of surgery, radiotherapy, systemic therapy, and observation on overall survival (OS) in men with nonmetastatic ductal PCa.

MATERIALS AND METHODS

We selected 1,656 cases of nonmetastatic ductal PCa, diagnosed between 2004 and 2015, within the National Cancer Database. Covariates included age, race, Charlson comorbidity score, clinical T stage, clinical lymph node stage, serum prostate specific antigen (PSA), income, hospital type, insurance status, year of diagnosis, and location of residence. Cox regression analysis tested the impact of treatment (surgery, radiotherapy, systemic therapy, and observation) on OS.

RESULTS

In men with nonmetastatic ductal PCa, median (interquartile range [IQR]) age and PSA were 67 (60-73) years and 6.2 (4.2-10.7) ng/ml, respectively. Advanced local stage (≥cT3a) was most frequently observed in patients initially treated with systemic therapy (34.8%), followed by those treated with radiotherapy (18.1%), surgery (7.1%) and observation (6.4%, P< 0.001). Serum PSA at presentation was highest in the systemic therapy cohort (median 16.0 ng/ml, IQR: 4.9-37.7), followed by the radiotherapy cohort (median 7.2 ng/ml, IQR: 4.1-12.2), observation cohort (median 7.0 ng/ml, IQR: 4.3-13.3) and surgery cohort (median 5.9 ng/ml, IQR: 4.3-9.2, P< 0.001). Multivariable analysis showed that in comparison to men treated surgically, OS was significantly lower for patients receiving radiotherapy (HR 2.2; 95% CI: 1.5-3.2), under observation (HR 4.6; 95% CI: 2.8-7.6) and receiving systemic therapy (HR 5.2; 95% CI: 3.0-9.1) as an initial course of treatment.

CONCLUSIONS

While limited by its retrospective nature, our study shows that starting treatment with surgery is associated with more favorable long-term OS outcomes than radiotherapy, systemic therapy or observation.

A Japanese patient with ductal carcinoma of the prostate carrying an adenomatosis polyposis coli gene mutation: a case report

Background

Ductal carcinoma of the prostate is a histological subtype with a higher mortality than acinar adenocarcinoma. The number of cases is small and there are no treatment guidelines. We believe that this is the first report of ductal carcinoma of the prostate with an adenomatosis polyposis coli (APC) gene mutation in Japan.

Case presentation

An 85-year-old man presented with gross hematuria, and a papillary tumor in the prostatic urethra that was diagnosed as ductal carcinoma of the prostate following transurethral resection. Genetic analysis found an APC mutation with loss of heterozygosity. Immunostaining revealed focal nuclear translocation of β-catenin. APC mutations associated with loss of β-catenin degradation in the Wnt signaling pathway and result in over accumulation of β-catenin are thought to increase mortality. In this patient, β-catenin migrated into tumor cell nuclei.

Conclusion

To the best of our knowledge, this is the first report of ductal carcinoma of the prostate with an APC mutation in Japan. The development of a therapeutic Wnt inhibitor is discussed.

The Role of Radiotherapy Among Patients With Prostate Ductal Adenocarcinoma

INTRODUCTION

The aim of this study was to perform a Surveillance, Epidemiology, and End Results (SEER) analysis on the effect of radiotherapy (RT) on survival among patients with prostate ductal adenocarcinoma (DA), a rare variant of prostate cancer.

PATIENTS AND METHODS

Cases of T1 to 4 N0 M0 prostate DA diagnosed between 2004 and 2013 were extracted from SEER. The association between categorical variables and radiation therapy was assessed for statistical significance using the χ² test or Fisher exact test. Difference in continuous variables across the RT groups was assessed for statistical significance using the 2-sample t test or non-parametric test. The distribution of overall survival (OS) and disease-specific survival (DSS) between the RT groups was assessed using the Kaplan-Meier method and the log rank test and after propensity matching. The association between hazards of death (HR) and covariates was examined using Cox proportional hazards model. A 2-sided P-value of .05 was used to determine statistical significance.

RESULTS

A total of 205 patients met inclusion criteria. On univariate analysis, RT was associated with significant improvement in OS and DSS. On multivariate Cox regression, RT significantly decreased risk of death for both OS and DSS (HR, 0.516; 95% confidence interval [CI], 0.273-0.978 and HR, 0.232; 95% CI, 0.082-0.658, respectively). After propensity score matching, RT demonstrated a persistent improvement in both OS and DSS.

CONCLUSIONS

RT decreased risk of death for both OS and DSS in patients with node-negative, nonmetastatic prostate DA on multivariable analysis. RT was also associated with improved OS and DSS after propensity matching.

Non-metastatic ductal adenocarcinoma of the prostate: pattern of care from an uro-oncology multidisciplinary group

PURPOSE

To retrospectively review our 20 year experience of multidisciplinary management of non-metastatic ductal prostate cancer (dPC), a rare but aggressive histological subtype of prostate cancer whose optimal therapeutic approach is still controversial.

METHODS

Histologically confirmed dPC patients undergoing primary, curative treatment [radical prostatectomy (RP), external beam radiotherapy (EBRT), and androgen deprivation therapy (ADT)] were included, and percentage of ductal and acinar pattern within prostate samples were derived. Survival outcomes were assessed using the subdistribution hazard ratio (SHR) and Fine-and-Gray model.

RESULTS

From January 1997 to December 2016, 81 non-metastatic dPC fitted selection criteria. Compared to surgery alone, SHR for progression-free survival and cancer-specific mortality were 2.8 (95% CI 0.6-13.3) and 1.3 (95% CI 0.1-16.2) for exclusive EBRT, 2.7 (95% CI 0.6-13.0) and 6.5 (95% CI 0.6-69.8) for adjuvant EBRT, 4.9 (95% CI 0.7-35.5) and 5.8 (95% CI 0.5-65.6) for salvage EBRT post-prostatectomy recurrence, and 3.2 (95% CI 0.7-14.0) and 3.9 (95% CI 0.3-44.1) for primary ADT (P = 0.558; P = 0.181), respectively. Comparing multimodal treatment and monotherapy confirmed the above trends. Local recurrence more typically occurred in pure dPC patients, mixed histology more frequently produced metastatic spread (29.6% relapse in total, P = 0.026).

CONCLUSION

Albeit some limitations affected the study, our findings support the role of local treatment to achieve better disease control and improve quality of life. Different behavior, with typical local growth in pure dPC, higher distant metastatization in the mixed form, might influence treatment response. Given its poor prognosis, we recommend multidisciplinary management of dPC.

Patterns of metastases of prostatic ductal adenocarcinoma

BACKGROUND

The current study was conducted to investigate the patterns of metastases in men with metastatic prostatic ductal adenocarcinoma (DAC) and recurrence patterns after therapy.

METHODS

All patients with a new diagnosis of DAC with de novo metastases and those with localized disease who developed metastases after treatment and were treated at the study institution from January 2005 to November 2018 were included. All patient and tumor characteristics and outcome data were collected.

RESULTS

A total of 164 patients (37.7%) had metastatic DAC, including 112 with de novo metastases and 52 who developed metastases after treatment. Men with de novo metastases were found to have a significantly higher median prostate-specific antigen level and International Society of Urological Pathology grade but a lower cT3 and/or T4 classification compared with those with metastases that developed after treatment (all P < .05). Approximately 87% of men with de novo metastases progressed despite multiple systemic therapies, 37.6% required intervention for the palliation of symptoms, and 10.1% responded to systemic therapy and underwent treatment of the primary tumor. Men with de novo metastatic DAC and those who developed metastases after treatment had multiple metastatic sites (including bone and viscera), with higher rates of lung metastases noted in the posttreatment group (23.2% vs 44.2%; P = .01). A total of 45 patients who were treated with curative intent developed metastases at a median of 22 months (range, 0.9-74.8 months) after treatment, at low prostate-specific antigen levels (median, 4.4 ng/mL [interquartile range, 1.7-11.1 ng/mL]).

CONCLUSIONS

The current study described the metastatic patterns of DAC in both patients with de novo metastatic disease and those who later progress to metastases. Men receiving treatment for DAC with curative intent require stringent long-term follow-up with imaging modalities, including chest imaging given the predilection toward lung metastases noted among these patients.

HoxB13 expression in ductal type adenocarcinoma of prostate: clinicopathologic characteristics and its utility as potential diagnostic marker

The histologic criteria and selective biomarkers of prostate ductal type adenocarcinoma (DAC) are relatively unknown compared to that known about acinar type adenocarcinoma (AAC). It is known that genetic alteration in Hox13 gene is associated with carcinogenesis of prostate cancer. In this study, we investigated clinicopathologic characteristics of HoxB13 expression in prostate cancer and compared clinicopathologic profiles of DAC and AAC of prostate. After slide review, some morphological variants of DAC, equivalent to Gleason pattern 3 and 5 of AAC were identified. High level of HoxB13 expression was identified in 46.5% (46 out of 99 cases) and 39.2% (31 out of 79 cases) of cases that belong to the training set and test set, respectively. In the training set, high level of HoxB13 expression was significantly correlated with DAC (P < 0.001), higher Gleason score (P < 0.001), advanced pathologic T stage (P = 0.010), and occurrence of biochemical recurrence (BCR; P < 0.001). The test set confirmed that high level of HoxB13 expression was associated with DAC (P < 0.001), higher Gleason score (P = 0.001), advanced pathologic T stage (P < 0.001), and occurrence of BCR (P < 0.001). Our findings suggest that HoxB13 may be a useful diagnostic marker for detection of DAC and a prognostic marker for prediction of BCR.

Prostatic Ductal Adenocarcinoma Controlled for Cancer Grade and Tumor Volume Does Not Have an Independent Effect on Adverse Radical Prostatectomy Outcomes Compared to Usual Acinar Prostatic Adenocarcinoma

OBJECTIVE

To study if prostatic ductal adenocarcinoma (PDA) controlled by Grade Group (GG), PSA, and tumor volume (TV) is an independent predictor of adverse radical prostatectomy (RP) outcomes.

MATERIALS

One-hundred and twenty-eight PDA and 1141 acinar continuous RPs were studied. Each tumor nodule (TN) was individually graded, staged, and its TV measured. Univariate analysis (UVA) identified features associated with lymph node metastasis (LN+), extraprostatic extension (EPE), positive surgical margins (SM+), and seminal vesicle invasion (SV+). We then assessed PDA effect on RP outcomes in a multivariate analysis (MVA).

RESULTS

In 127 cases PDA was present in 1 TN and no TN was pure PDA. One-hundred and twenty-three cases had PDA in TNs with highest grade, stage, and TV. Patients with PDA were older (65 vs 63 years, P < 0.001), had higher GG (P < 0.001), and LN+ (6.3% vs 2.7%, P = 0.049). Controlling these variables by GG eliminated statistical significance. Overall, there were 3249 separate TNs (129 PDA and 3120 acinar). In UVA, PDA predicted EPE (92/124 vs 517/3045), SV+ (28/1129 vs 116/3,120), and SM+ (51/129 vs 296/3120), all P < 0.001. In MVA, PDA lost its effect on EPE (OR = 0.88, P = 0.64), SM+ (OR = 0.86, P = 0.5), and SV+ (OR = 0.99, P = 0.98).

CONCLUSION

Controlled for grade and TV, PDA was not an independent predictor of adverse RP outcomes, but former 2 were. Hence, higher GG and TV associated with PDA TNs may be predictive of adverse RP outcomes rather than PDA by itself. These conclusions may be used in preoperative risk stratification and definitive therapy planning when PDA is identified on needle biopsy.

Does ductal adenocarcinoma of the prostate (DA) have any prognostic impact on patients with de novo metastatic prostate cancer?

BACKGROUND

The prognostic value of ductal adenocarcinoma of the prostate (DA) in nonmetastatic prostate cancer (PCa) has been identified in many studies. However, it remains unknown whether DA is an adverse prognostic factor in metastatic PCa (mPCa).

METHOD

Data from 634 mPCa patients histopathologically documented with DA or/and acinar adenocarcinoma of the prostate in our center between 2012 and 2018 were retrospectively analyzed. Propensity score matching (PSM) was used to balance the baseline features. Data from the Surveillance, Epidemiology, and End Results (SEER) database were utilized to validate our findings. Castration-resistant PCa-free survival (CFS), overall survival (OS), and cancer-specific survival (CSS) were set as endpoints.

RESULTS

DA was confirmed in 35 of 634 (5.5%) patients. Among the DA-positive patients, 7 of 35 (20%) and 28 of 35 (80%) harbored high (DA ≥ 50%) and low (DA < 50%) DA components, respectively. DA was not associated with poorer median CFS (mCFS) or median OS (mOS) either before PSM (mCFS: 16.9 vs 18.4 month, P = .814; mOS: 42.0 vs 70.1 month, P = .796) or after PSM (mCFS: 16.9 vs 16.9 month, P = .949; mOS: 42.0 vs 79.9 month, P = .960). Likewise, in the SEER data, DA-positive patients (n = 15 153) shared similar median CSS (25.0 vs 28.0 month, P = .206) and OS (26.0 vs 35.0 month, P = .095) with DA-negative patients (n = 70). No prognostic difference was found between patients with high and low DA components.

CONCLUSION

We conducted the first study investigating the prognostic value of DA in de novo mPCa. DA was not associated with adverse clinical outcomes in mPCa patients. These findings are helpful for prognostic evaluation, treatment decision making and counseling in mPCa patients.

PIN-like (Ductal) Adenocarcinoma of the Prostate

Prostatic intraepithelial neoplasia like (PIN-like ductal) carcinoma are rare tumors characterized by crowded, often cystically dilated glands architecturally resembling high-grade prostatic intraepithelial neoplasia, lined by malignant pseudostratified columnar epithelium. The largest prior series studied 9 radical prostatectomies (RPs) and suggested a behavior similar to Gleason score 6. We sought to investigate this rare tumor within a larger series. PIN-like carcinoma cases were identified from in-house and consultation files from 2008 to 2017. A total of 190 total cases were identified (in-house cases n=8, 4.2%, consult cases n=182, 95.8%); the diagnosis of PIN-like carcinoma was made on needle biopsy (n=181), transurethral resection (n=5) and RP (n=4). The average age was 70 years. The average number of cores with involvement by PIN-like carcinoma was 2 (1 to 12). The average maximum percentage by a PIN-like carcinoma component of any core was 43.5% (5% to 90%). In 58/181 (32.0%) biopsy cases, due to selective parts having been submitted for consultation, it was unknown whether there was an association with acinar carcinoma. A total of 72 cases showed exclusively PIN-like carcinoma. Highest grade groups (GGs) on biopsies with known acinar or papillary/cribriform ductal carcinomas were GG1 (n=23, 45.1%), GG2 (n=14, 27.5%), GG3 (n=9, 17.6%), GG4 (n=4, 7.8%), and GG5 (n=1, 2.0%). Of 44 cases where the patient would be considered eligible for active surveillance, 18 (41.0%) underwent RP. RP slides were available in 16 cases; 3 (18.8%) cases diagnosed on biopsy did not show PIN-like carcinoma on review of RP slides. PIN-like carcinoma was present without an associated acinar tumor in 3 (23.1%) RPs; 2 showing tumors with large, cystic dilated glands extending into periprostatic tissue. In 7/13 cases (53.8%), the acinar component was the dominant tumor and the PIN-like carcinoma component was small (<1 cm). The overall grade at RP was GG1 (5/13, 38.5%) and GG2 (8/13, 61.5%). In all cases with an acinar component, the acinar tumor was anatomically distinct from the PIN-like carcinoma tumor. The GGs of the separate acinar tumors were GG1 (6/10) and GG2 (4/10) with percent pattern 4 ≤5% in all 4 cases. No cases were associated with metastases to lymph nodes or seminal vesicle invasion. Extraprostatic extension was present in 6/13 (46.1%) cases, from the acinar component in 1 (7.7%) case and the PIN-like carcinoma component in 5 (83.3%) cases. In all 5 cases, there was a peculiar morphology of thin papillary projections into cystic dilated PIN-like carcinoma glands. Immunohistochemical expression of ERG was positive in 1/11 (9.1%) case. 1/11 (9.1%) case showed heterogeneous loss of PTEN. Overall, PIN-like carcinoma tumors are limited in size, not advanced in stage, not associated with high-grade cancer on RP, and show low rates of Gleason pattern 4 and TMPS-ERG rearrangement. Our study supports grading classic PIN-like carcinoma as Gleason pattern 3; at the current time we recommend grading thin papillary projections of PIN-like carcinoma as pattern 4. Longer term studies will be needed to determine the clinical significance of thin papillary projections in PIN-like carcinoma.

PD-L1 expression and deficient mismatch repair in ductal adenocarcinoma of the prostate

This study aimed to investigate the expression of programmed death receptor ligand 1 (PD-L1) and deficient mismatch repair (dMMR) in ductal adenocarcinoma of the prostate. A tissue microarray of 32 ductal and 42 grade-matched acinar adenocarcinomas was used. Slides were stained for PD-L1, PD-L2, MMR proteins, CD4 and CD8. PD-L1 expression in tumor cells was only seen in 3% (1/34) of ductal and 5% (2/42) of acinar adenocarcinomas (p = 1.0), while PD-L1 expression in tumor-infiltrating immune cells was seen in 29% (10/34) of ductal and 14% (6/42) of acinar adenocarcinomas (p = 0.16). dMMR, as defined by loss of one or more of the MMR proteins, was identified in 5% (4/73) of cases, including 1 ductal and 3 acinar adenocarcinomas. There was a suggested association between infiltration of CD8+ lymphocytes and ductal subtype (p = 0.04) but not between CD4+ lymphocytes and tumor type (p = 0.28). The study shows that both dMMR and PD-L1 expression is uncommon in tumor cells of both ductal and acinar adenocarcinoma of the prostate, while PD-L1 expression in tumor-infiltrating immune cells is a more common finding.

Contemporary Comparison of Clinicopathologic Characteristics and Survival Outcomes of Prostate Ductal Carcinoma and Acinar Adenocarcinoma: A Population-Based Study

PURPOSE

To investigate clinicopathologic characteristics and cancer-specific mortality (CSM) rates of ductal carcinoma (DC) versus the common acinar adenocarcinoma in nonmetastatic and metastatic (M1) prostate cancer patients.

PATIENTS AND METHODS

Within the Surveillance, Epidemiology, and End Results database (2004-2015), we identified patients with histologically confirmed prostate adenocarcinoma who harbored either DC (n = 581) or acinar adenocarcinoma (n = 489,296). Kaplan-Meier and 4:1 propensity score-matched multivariable Cox regression models adjusted for clinical and pathologic parameters were used to test for CSM differences. Three separate analyses were performed on all patients with nonmetastatic disease, patients with nonmetastatic patients treated with radical prostatectomy only, and patients with metastatic disease.

RESULTS

DC was identified in 502 (0.10%) of 469,946 patients with nonmetastatic disease and 79 (0.39%) of 19,931 patients with metastatic disease. In patients with nonmetastatic disease, 253 (50.4%) DC patients underwent radical prostatectomy, 61 (12.2%) DC patients received external-beam radiotherapy, and 188 (37.4%) received other treatment modalities. In multivariable analyses, DC was associated with higher CSM in the overall nonmetastatic patient population (hazard ratio [HR] = 1.8; 95% confidence interval [CI], 1.3-2.6; P = .001), in the nonmetastatic radical prostatectomy population (HR = 2.8; 95% CI, 1.3-6.0; P < .01), and in the M1 population (HR = 1.6; 95% CI, 1.1-2.2; P < .01).

CONCLUSION

Prostate cancers of ductal origin represent a rare entity among patients with nonmetastatic disease as well as among patients with metastatic disease, and regardless of stage, DC behaves more aggressively.

Prostatic ductal adenocarcinoma with cribriform architecture has worse prognostic features than non-cribriform-type

Prostatic ductal adenocarcinoma (PDA) is a rare histologic subtype of prostate cancer characterized by large glands lined with tall columnar pseudostratified epithelium. PDA has several architectural patterns, with papillary and cribriform being the most common. The cribriform pattern of acinar carcinoma has shown to be associated with a worse prognosis in terms of disease progression and disease-specific mortality. However, the significance of cribriform pattern in PDA is unknown. In this study, we sought to compare the adverse pathologic features between cribriform-type and non-cribriform-type PDA, and between PDA and acinar carcinoma with Gleason scores 8-10. We identified PDA cases diagnosed between 2008 and 2018 and 428 radical prostatectomy (RP) specimens containing Gleason 8-10 acinar carcinoma. The slides of all PDA cases were reviewed, and pathologic features were recorded. We found that the vast majority of PDA contained admixed acinar carcinoma, with a median percentage of the ductal component of 50% (range 5-100). 29% of PDA was graded as Grade Group 4 and 35.5% as Grade Group 5. At the time of RP, 45.2% of cases presented as pathologic stage T3a and 29% as T3b. Cribriform-type PDA demonstrated a significantly higher likelihood of extraprostatic extension (84% vs 33.3%, p = 0.01), seminal vesical invasion (36% vs 0%, p = 0.04), lymphovascular invasion (40% vs 0%, p = 0.03) and advanced pathologic stage (84% vs 33.3%, p = 0.01) compared to PDA without cribriform architecture. The proportion of stage ≥pT3 tumors in PDA was similar compared to that in Gleason 8-10 acinar carcinoma (74.2% vs 70.8%, p = 0.68).

Prognostic values of clinicopathological characteristics and survival outcomes in prostate infiltrating ductal carcinoma: a population-based study

Infiltrating ductal carcinoma (IDC) is a rare histologic subtype of prostate cancer. We investigated the clinicopathological features and prognosis of IDC compared with acinar cell carcinoma (ACC). We identified 3814 men diagnosed with prostate cancer between 2004 to and 2013 in the Surveillance, Epidemiology, and End Results database, including 511 IDC and 3303 ACC cases. Prostate cancer-specific survival (PCSS) was compared using univariate and multivariate Cox proportional hazards models. Generally, IDC occurred in older men (≥ 65 years old) and presented with larger sizes, and higher grades, American Joint Committee on Cancer (AJCC) stages, AJCC T stages, lymph node positive rates and metastasis rates. Men with IDC were less likely to undergo radical prostatectomy, but more likely to be treated with adjuvant radiation than men with ACC. Five-year PCSS rates were significantly worse in IDC. In the multivariate analysis, patients with ACC had a better PCSS than patients with IDC. In conclusion, IDC has unique clinicopathological characteristics and has worse prognosis than ACC. Multivariable Cox regression analysis showed that age over 85 years, higher grade and T stage, and metastasis at diagnosis were independent prognostic factors of worse survival outcomes, whereas radical prostatectomy was an independent prognostic factor of better survival outcomes.

Population-based study of the incidence and survival for intraductal carcinoma of the prostate

PURPOSE

The degree to which intraductal carcinoma of the prostate (IDC-P) affects clinical course remains poorly understood owing to small sample sizes from single-center studies. We sought to determine prognostic factors and outcomes associated with IDC-P in radical prostatectomy (RP) specimens.

MATERIALS AND METHODS

This is a retrospective study of RP during 2004 to 2013 using Surveillance, Epidemiology, and End Results to compare IDC-P with non-IDC-P. The effect of IDC-P on overall and disease-specific survival was assessed using Cox regression with a median follow-up of 4.8 years (interquartile range [IQR]: 2.6-7.0y; P = 0.01). Median prostate-specific antigen at diagnosis in IDC-P vs. non-IDC-P was similar (P = 0.23) at 6.2 (IQR: 4.6-13.0) vs. 6.1ng/ml (IQR: 4.6-9.8).

RESULTS

We identified 159,777 RP from 2004 to 2013, and 242 (0.002%) had IDC-P pathologic features. IDC-P was associated with a greater likelihood of extraprostatic stage, pT3/T4, 45.9% vs. 21.6% (P<0.001), higher grade, GS≥ 7, 79.3% vs. 62.7% (P<0.001), lymph node metastases, 5.8% vs. 2.4% (P<0.001), and positive surgical margins, 25.6% vs. 19.5% (P = 0.02). IDC-P was associated with a 3-fold increase in prostate cancer-specific mortality relative to non-IDC-P (hazard ratio = 3.0, 95% CI: 1.5-5.7; P<0.01). Limitations include retrospective design and potential underreporting of IDC-P that leads to underestimation of the true effect size.

CONCLUSIONS

The significance of IDC-P features has been recently recognized by the World Health Organization and it is associated with high-grade, extraprostatic features, and worse prostate cancer-specific mortality. Understanding its prognostic significance better guides adjuvant therapies and clinical trials.

Ductal adenocarcinoma of the prostate: Clinical and biological profiles

BACKGROUND

Ductal adenocarcinoma (DAC) is a rare and aggressive subtype of prostate cancer (PCa). In the present study, we analyzed the clinical and biological characteristics of DAC, in comparison with high grade conventional acinar PCa.

METHODS

Samples and data were retrospectively collected from seven institutions and centrally reviewed. Immunohistochemistry was performed on tissue microarrays to assess the expression of candidate proteins, based on the molecular classification of PCa, including ERG, PTEN, and SPINK1. SPOP mutations were investigated from tumor DNA by Sanger sequencing. Relationships with outcome were analyzed using log-rank analysis and multivariable Cox regression.

RESULTS

Among 56 reviewed prostatectomy specimens, 45 cases of DAC were finally confirmed. The pathological stage was pT3 in more than 66% of cases. ERG was expressed in 42% of DAC, SPINK1 in 9% (all ERG-negative), and two cases (ERG-negative) harbored a SPOP mutation. Compared to high grade conventional PCa matched for the pathological stage, cell proliferation was higher (P = 0.04) in DAC, and complete PTEN loss more frequent (P = 0.023). In multivariate analysis, SPINK1 overexpression (P = 0.017) and loss of PSA immunostaining (P = 0.02) were significantly associated with biochemical recurrence.

CONCLUSION

these results suggest that, despite biological differences that highlighted DAC aggressiveness, the molecular classification recently proposed in conventional PCa could also be applied in DAC.

Diverse Immunoprofile of Ductal Adenocarcinoma of the Prostate with an Emphasis on the Prognostic Factors

BACKGROUND

Ductal adenocarcinoma (DAC) of the prostate is an uncommon histologic subtype whose prognostic factors and immunoprofile have not been fully defined.

METHODS

To define its prognostic factors and immunoprofile, the clinicopathological features, including biochemical recurrence (BCR), of 61 cases of DAC were analyzed. Immunohistochemistry was performed on tissue microarray constructs to assess the expression of prostate cancer-related and mammalian target of rapamycin (mTOR) signaling-related proteins.

RESULTS

During the median follow-up period of 19.3 months, BCR occurred in 26 cases (42.6%). DAC demonstrated a wide expression range of prostate cancer-related proteins, including nine cases (14.8%) that were totally negative for pan-cytokeratin (PanCK) immunostaining. The mTOR signaling-related proteins also showed diverse expression. On univariate analysis, BCR was associated with high preoperative serum levels of prostate-specific antigen (PSA), large tumor volume, predominant ductal component, high Gleason score (GS), comedo-necrosis, high tumor stage (pT), lymphovascular invasion, and positive surgical margin. High expressions of phospho-mTOR (p-mTOR) as well as low expressions of PSA, phospho-S6 ribosomal protein (pS6) and PanCK were associated with BCR. On multivariable analysis, GS, pT, and immunohistochemical expressions of PanCK and p-mTOR remained independent prognostic factors for BCR.

CONCLUSIONS

These results suggest GS, pT, and immunohistochemical expressions of PanCK and p-mTOR as independent prognostic factors for BCR in DAC. Since DAC showed diverse expression of prostate cancer-related proteins, this should be recognized in interpreting the immunoprofile of DAC. The diverse expression of mTOR-related proteins implicates their potential utility as predictive markers for mTOR targeted therapy.

Modern-day prostate cancer is not meaningfully associated with lower urinary tract symptoms: Analysis of a propensity score-matched cohort

INTRODUCTION

We sought to determine if prostate cancer (PCa) is associated with worse lower urinary tract symptoms (LUTS) than matched benign prostates, with attention to cancer characteristics, in a contemporary cohort.

METHODS

Using a single-institution database (January 1, 2009-June 30, 2013), men diagnosed with PCa on biopsy and controls with negative biopsies were matched 1:1 on age, prostate volume, and a propensity score predicting the probability of PCa diagnosis. International Prostate Symptom Score (IPSS) was compared between PCa cases and controls using paired statistics, stratifying on grade, cancer volume, stage, and D'Amico risk group. Sensitivity analyses were performed separately, repeating the match for high-grade, high-volume, and high-stage cancers only, and excluding users of benign prostatic hyperplasia medications.

RESULTS

In our cohort of 1330 men (665 with PCa), there were 284 (42.7%) Gleason 6 cancers (Grade Group 1), 315 (47.4%) Gleason 7 cancers (Grade Group 2-3), and 66 (9.9%) Gleason 8-10 cancers (Grade Group 4-5). There was no difference in IPSS between PCa cases (median 6.5, interquartile range [IQR] 3-12) and benign controls (median 7, IQR 3-13; p=0.34). Subgroup analyses based on cancer grade, volume, or stage, showed no significant differences in IPSS between men with and without PCa, except among men with cT2b-cT4 PC (median 9, IQR 5-16) vs. matched benign counterparts (median 8, IQR 3-12; p=0.03). Sensitivity analyses supported these findings.

CONCLUSIONS

Modern PCa does not appear to be associated with worse LUTS compared to benign prostates of the same size. Outlet obstruction is likely a late event in the natural history of PCa. This has implications for timely PCa detection, which should ideally be prior to the onset of LUTS.

Intraductal Carcinoma of the Prostate Gland: Recent Advances

Intraductal carcinoma of the prostate (IDC-P) is characterized by prostatic carcinoma involving ducts and/or acini. The presence of IDC-P is usually associated with a high-grade Gleason score, large tumor volume, and adverse prognostic parameters, including extraprostatic extension and seminal vesicle invasion. When present, IDC-P is associated with worse outcomes, regardless of treatment status. IDC-P is included in a broader diagnostic category of atypical cribriform lesions of the prostate gland. This category of lesions also includes high-grade prostatic intraepithelial neoplasia (HGPIN), urothelial carcinoma involving prostatic ducts or acini, and prostatic ductal adenocarcinoma, amongst other intraductal proliferations. Differentiating between these entities is important as they have differing therapeutic and prognostic implications for patients, although differential diagnosis thereof is not always straightforward. The present review discusses IDC-P in regards to its morphological characteristics, molecular features, and clinical outcomes. Given the current state of knowledge, the presence of IDC-P should be evaluated and documented correctly in both radical prostatectomy and needle biopsy specimens, and the clinical implications thereof should be taken into consideration during treatment and follow up.

Metachronous anterior urethral metastasis of prostatic ductal adenocarcinoma

Prostate cancer is increasing in frequency in Korea. Among them, ductal adenocarcinoma (DCP) has a more aggressive and poor prognosis than acinar adenocarcinoma (ACP), despite its low incidence. Patients usually present with symptoms of lower urinary tract symptoms and hematuria due to increasing tumor mass within the lumen of the prostatic urethra, making diagnosis of DCP by the transrectal prostate biopsy difficult. DCP is often metastasized at the time of diagnosis. DCP is transferable to most other organs but the metastasis to the anterior urethra is rare. There is no doubt that localized DCP requires radical prostatectomy (RP) but the guidelines for adjuvant therapy after RP have not yet been established. Methods of the treatment are confounded by individual differences, and arriving at a consensus is challenging due to insufficient data. We report a case of DCP and urethral metastasis after RP, thus aiding in the determination of treatment guidelines.

An unusual cystic presentation of ductal carcinoma of the prostate

A 74-year-old male came to our clinic for rectal tenesmus, lower urinary tract symptoms and a previous episode of acute retention of urine. Computed tomography (CT) and magnetic resonance imaging (MRI) scan of abdomen showed a multiloculated, cystic formation of 12 cm in the pelvic cavity to the left, with compression of the prostate, bladder, sigmoid and rectum, and its extension imprinted the back of the pubis and back bladder. Saturation prostate biopsy was negative for carcinoma. The histology of transurethral resection of bladder formation revealed flogistic tissue. Cistoprostatectomy and ureteroileal pouch with Wallace anastomosis, removal of the rectum and colostomy with Hartmann pouch were performed. The histopatology showed a ductal carcinoma of the prostate.

Advanced prostatic ductal carcinoma in a patient with a long survival time following a total pelvis exenteration: A case report

Ductal adenocarcinoma of the prostate (DAP) is a rare variant of prostate cancer, and has poorly-identified clinical characteristics. Few cases have been previously reported in Chinese males and DAP is more commonly reported in Caucasian males over 70-years of age. In the present study, a 55-year-old Chinese male patient that demonstrated typical lower urinary tract symptoms and normal prostatic-specific antigen levels underwent a transurethral resection of the prostate. The patient was subsequently diagnosed with DAP. A total pelvis exenteration was then conducted successfully. During the 40-month follow-up, the patient remained progression-free. A review of the literature was conducted in order to assess the clinical course, diagnosis, prognosis and optimal management for DAP. The review indicated that DAP is more likely to demonstrate an aggressive clinical course and an unfavorable prognosis; therefore, once the diagnosis has been confirmed, an aggressive management strategy is recommended for the patient, even in the case of metastatic disease.

Prostatic ductal adenocarcinoma: An aggressive variant that is underdiagnosed and undersampled on transrectal ultrasound (TRUS)-guided needle biopsy

INTRODUCTION

We sought to determine if prostatic ductal adenocarcinoma is undersampled and/or underdiagnosed at transrectal ultrasound (TRUS)-guided biopsy.

METHODS

With institutional review board approval, we searched our pathology database between 2008 and 2014 for patients with a diagnosis of ≥10% ductal adenocarcinoma on radical prostatectomy and available TRUS-guided needle biopsy specimens. Three blinded genitourinary pathologists independently examined the biopsy slides. The presence or absence of ductal adenocarcinoma was determined. Diagnostic accuracy was calculated using consensus diagnosis as the reference standard. Inter-observer agreement was assessed using Cohen's kappa coefficient.

RESULTS

Based on consensus review, 66.7% (12/18) biopsy specimens demonstrated ductal adenocarcinoma and 33.3% (6/18) demonstrated conventional acinar prostatic adenocarcinoma. The sensitivity/specificity for each reader (R) was: 83/100% (R1), 100/83% (R2) and 58/83% (R3) and the inter-observer agreement was only fair (K=0.32). Only two of the original needle-biopsy reports correctly identified ductal adenocarcinoma (sensitivity = 17%). The main limitations of the study are the relatively small sample size and the potential for selection bias since we could only examine patients who underwent radical prostatectomy.

CONCLUSIONS

Prostatic ductal adenocarcinoma may be undersampled at TRUS-guided biopsy and in this study was under-reported in routine clinical practice. This highlights the importance of increased awareness of ductal adeoncarcinoma and the need for clear diagnostic criteria. These findings have significant clinical impact especially when determining candidacy for active surveillance protocols.