Any proportion of ductal adenocarcinoma in radical prostatectomy specimens predicts extraprostatic extension

Ductal, intraductal, and cribriform carcinoma of the prostate: Molecular characteristics and clinical management

Prostatic acinar adenocarcinoma accounts for approximately 95% of prostate cancer (CaP) cases. The remaining 5% of histologic subtypes of CaP are known to be more aggressive and have recently garnered substantial attention. These histologic subtypes - namely, prostatic ductal adenocarcinoma (PDA), intraductal carcinoma of the prostate (IDC-P), and cribriform carcinoma of the prostate (CC-P) - typically exhibit distinct growth characteristics, genomic features, and unique oncologic outcomes. For example, PTEN mutations, which cause uncontrolled cell growth, are frequently present in IDC-P and CC-P. Germline mutations in homologous DNA recombination repair (HRR) genes (e.g., BRCA1, BRCA2, ATM, PALB2, and CHEK2) are discovered in 40% of patients with IDC-P, while only 9% of patients without ductal involvement had a germline mutation. CC-P is associated with deletions in common tumor suppressor genes, including PTEN, TP53, NKX3-1, MAP3K7, RB1, and CHD1. Evidence suggests abiraterone may be superior to docetaxel as a first-line treatment for patients with IDC-P. To address these and other critical pathological attributes, this review examines the molecular pathology, genetics, treatments, and oncologic outcomes associated with CC-P, PDA, and IDC-P with the objective of creating a comprehensive resource with a centralized repository of information on PDA, IDC-P, and CC-P.

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.

High GLUT1 membrane expression and low PSMA membrane expression in Ductal Adenocarcinoma and Intraductal Carcinoma of the prostate

BACKGROUND

Both Ductal Adenocarcinoma (DAC) and Intraductal Carcinoma (IDC) of the prostate are generally associated with aggressive clinical behavior and poor prognosis, which were linked with discordant FDG positivity and low Prostate-Specific Membrane Antigen (PSMA) expression. A recent study only cited a DAC patient with low 68Ga-PSMA-11 PET/CT uptake but high 18F-FDG PET/CT uptake, however, there is lack of directly compared articles nor large data sets. Hence, the objective of this study was to investigate the expression of PSMA and GLUT1 in DAC and IDC-P patients.

METHODS

The study was conducted on 87 DAC or/and IDC-P patients without any treatment and 97 PAC patients with a Gleason score ≥8 of prostate biopsies and prostatectomy samples between August 2017 and August 2022. We performed immunohistochemical staining and scoring of various cancer component samples from the patients to reflect the protein expression levels of PSMA and GLUT1.

RESULTS

PSMA expression in PAC was significantly higher than in DAC/IDC-P (141.2 vs 78.6, p < 0.001). There was no significant difference in PSMA expression between DAC/IDC-P and adjacent PAC (78.6 vs 93.4, p = 0.166). GLUT1 expression was higher in DAC/IDC-P than in adjacent PAC (68.6 vs 51.3, p = 0.007), but was still lower than that in pure PAC (68.6 vs 93.1, p = 0.0014). It is worth noting that GLUT1 membrane expression in DAC/IDC-P was significantly increased than in pure PAC (13.0 vs 6.6, p = 0.025), and in PAC adjacent to DAC/IDC-P (13.0 vs 2.0, p < 0.001).

CONCLUSIONS

In DAC/IDC-P tissues, PSMA expression is low, while GLUT1 expression, especially GLUT1 membrane expression is high. These findings imply that DAC/IDC-P may have higher glucose metabolic and raise interest in targeting membrane GLUT1 as a novel anticancer strategy for DAC/IDC-P and other prostate cancer with high glucose metabolism.

Impact of Epithelial Histological Types, Subtypes, and Growth Patterns on Oncological Outcomes for Patients with Nonmetastatic Prostate Cancer Treated with Curative Intent: A Systematic Review

CONTEXT

The optimal management for men with prostate cancer (PCa) with unconventional histology (UH) is unknown. The outcome for these cancers might be worse than for conventional PCa and so different approaches may be needed.

OBJECTIVE

To compare oncological outcomes for conventional and UH PCa in men with localized disease treated with curative intent.

EVIDENCE ACQUISITION

A systematic review adhering to the Referred Reporting Items for Systematic Reviews and Meta-Analyses was prospectively registered on PROSPERO (CRD42022296013) was performed in July 2021.

EVIDENCE SYNTHESIS

We screened 3651 manuscripts and identified 46 eligible studies (reporting on 1 871 814 men with conventional PCa and 6929 men with 10 different PCa UHs). Extraprostatic extension and lymph node metastases, but not positive margin rates, were more common with UH PCa than with conventional tumors. PCa cases with cribriform pattern, intraductal carcinoma, or ductal adenocarcinoma had higher rates of biochemical recurrence and metastases after radical prostatectomy than for conventional PCa cases. Lower cancer-specific survival rates were observed for mixed cribriform/intraductal and cribriform PCa. By contrast, pathological findings and oncological outcomes for mucinous and prostatic intraepithelial neoplasia (PIN)-like PCa were similar to those for conventional PCa. Limitations of this review include low-quality studies, a risk of reporting bias, and a scarcity of studies that included radiotherapy.

CONCLUSIONS

Intraductal, cribriform, and ductal UHs may have worse oncological outcomes than for conventional and mucinous or PIN-like PCa. Alternative treatment approaches need to be evaluated in men with these cancers.

PATIENT SUMMARY

We reviewed the literature to explore whether prostate cancers with unconventional growth patterns behave differently to conventional prostate cancers. We found that some unconventional growth patterns have worse outcomes, so we need to investigate if they need different treatments. Urologists should be aware of these growth patterns and their clinical impact.

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.

WHO Classification of Tumours fifth edition: evolving issues in the classification, diagnosis, and prognostication of prostate cancer

The fifth edition of the WHO Classification of Tumours of the Urinary and Male Genital Systems encompasses several updates to the classification and diagnosis of prostatic carcinoma as well as incorporating advancements in the assessment of its prognosis, including recent grading modifications. Some of the salient aspects include: (1) recognition that prostatic intraepithelial neoplasia (PIN)-like carcinoma is not synonymous with a pattern of ductal carcinoma, but better classified as a subtype of acinar adenocarcinoma; (2) a specific section on treatment-related neuroendocrine prostatic carcinoma in view of the tight correlation between androgen deprivation therapy and the development of prostatic carcinoma with neuroendocrine morphology, and the emerging data on lineage plasticity; (3) a terminology change of basal cell carcinoma to "adenoid cystic (basal cell) cell carcinoma" given the presence of an underlying MYB::NFIB gene fusion in many cases; (4) discussion of the current issues in the grading of acinar adenocarcinoma and the prognostic significance of cribriform growth patterns; and (5) more detailed coverage of intraductal carcinoma of prostate (IDC-P) reflecting our increased knowledge of this entity, while recommending the descriptive term atypical intraductal proliferation (AIP) for lesions falling short of IDC-P but containing more atypia than typically seen in high-grade prostatic intraepithelial neoplasia (HGPIN). Lesions previously regarded as cribriform patterns of HGPIN are now included in the AIP category. This review discusses these developments, summarising the existing literature, as well as the emerging morphological and molecular data that underpins the classification and prognostication of prostatic carcinoma.

Ductal and acinar components of mixed prostatic adenocarcinoma frequently have a common clonal origin

BACKGROUND

Ductal adenocarcinoma (DA) is an aggressive subtype of prostate cancer. It is most commonly seen in mixed tumors together with conventional acinar adenocarcinoma (AA). The genetic profile of DA and its clonal origin is not fully characterized.

OBJECTIVE

To investigate whether DA represents a distinct genetic subtype and to investigate the somatic relationship between the ductal and acinar components of mixed cancers.

DESIGN, SETTING, AND PARTICIPANTS

In 17 radical prostatectomy specimens ductal and acinar tumor components from the same tumor foci were dissected. DNA was extracted and genomic sequencing performed. After exclusion of two cases with low cell yield, 15 paired samples remained for analysis.

RESULTS

In 12 of 15 cases a common somatic denominator was identified, while three cases had clonally separate components. In DA, TMPRSS2-ERG gene fusions were detected in 47% (7/15), clonal FOXA1 alterations in 33% (5/15) and SPOP alterations in 27% (4/15) of cases. In one case KIAA1549-BRAF fusion was identified. Genome doubling events, resulting in an increased ploidy, were identified in the DA in 53% (8/15) of cases, but not seen in any AA. PTEN and CTNNB1 alterations were enriched in DA (6/15) but not seen in any AA. No cancers showed microsatellite instability or high tumor mutation burden.

CONCLUSIONS

Ductal and acinar prostate adenocarcinoma components of mixed tumors most often share the same origin and are clonally related. DA components in mixed tumor often exhibit genome doubling events resulting in aneuploidy, consistent with the aggressive nature of high grade prostate cancer.

Prevalence of adverse pathology features in grade group 2 prostatectomy specimens with syn- or metachronous metastatic disease

BACKGROUND

To validate the importance of recently established adverse histopathology features (cribriform pattern and intraductal carcinoma) as contra-indication for deferred treatment of Gleason score 7 (3 + 4) (grade group [GG] 2) prostate cancer, we investigated their frequency in GG2 radical prostatectomies with syn- or metachronous metastatic disease.

METHODS

GG2 prostatectomy specimens of patients with concomitant lymph node metastasis or distant metastasis at follow-up were identified in a clinical database of a tertiary care center and their pathology was reviewed for pathological stage, lymphovascular invasion, Gleason grade 4 subpatterns, presence of tertiary grade 5, and ductal adenocarcinoma histology. A control group of 99 GG2 prostatectomy specimens who had no metastatic disease (controls) was reviewed for the same adverse pathological features.

RESULTS

Of 1860 GG2 prostatectomy specimens (operated between 2002 and 2020), 45 (2.4%) had concurrent regional lymph node metastases or distant metastases at follow-up. Pathological stage distribution of cases and controls was 24% and 79% pT2, 42% and 15% pT3a, 33% and 6.1% pT3b -T4, respectively (p < 0.001). Eleven of 45 cases (24%) had ≤10% Gleason grade 4 component. Cribriform pattern or intraductal carcinoma was present in 84% of cases versus 34% of controls (p < 0.001), tertiary grade 5 in 16% of cases versus 5% controls (p = 0.05) and ductal adenocarcinoma in 16% of cases versus 2% of controls (p = 0.004). Among the seven cases without cribriform or intraductal carcinoma, two displayed ductal adenocarcinoma features.

CONCLUSIONS

Well-established unfavorable histopathologic features (intraductal and cribriform pattern carcinoma, ductal adenocarcinoma) are represented in about 90% of GG2 prostate cancers with local or distant metastatic disease and are much less common (38%) in those without metastatic disease. Strikingly, about 25% of GG2 prostatectomy cases with metastatic disease had an organ-confined disease and/or a small percentage of Gleason grade 4 pattern. This further emphasizes the relative importance of these adverse histopathological features (cribriform, intraductal, and ductal adenocarcinoma) rather than percentage Gleason grade 4 as contra-indicator of deferred treatment for patients with GG2 prostate cancer.

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.

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.

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.

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.

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.

Initial Diagnosis and Detection of Very Late Local Recurrence of a Ductal Prostate Cancer due to a Ureteral Stone

We report the case of a 74-year-old patient in whom a ductal prostate cancer was incidentally endoscopically diagnosed in the course of ureteral stenting due to a left distal ureteral stone. The initial PSA was 0.8 μg/l and the digital rectal examination was not suspicious. A radical prostatectomy was performed, and the ensuing follow-up was unremarkable with no signs of recurrence. Fourteen years later, the patient presented with an obstructive pyelonephritis due to a left-sided ureteral stone requiring ureteral stenting. An exophytic tumor was seen in the lining of vesicourethral anastomosis and surgically excised after the pyelonephritis subsided. The histopathological and immunohistochemical analysis revealed a ductal cancer of the prostate consistent with a late local recurrence. Serum PSA was below the limit of detection. Re-staging performed by an MRI of the pelvis, thoracoabdominal CT scan, and gallium-68 PSMA-PET did not reveal any other signs of disease. The ensuing follow-up is planned with regular flexible cystoscopy and computed thoracoabdominopelvic CT scans.

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.

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).

Spectrum of Cribriform Proliferations of the Prostate: From Benign to Malignant

Context.—

The presence of cribriform glands/ducts in the prostate can pose a diagnostic challenge. Cribriform glands/ducts include a spectrum of lesions, from benign to malignant, with vastly different clinical, prognostic, and treatment implications.

Objective.—

To highlight the diagnostic features of several entities with a common theme of cribriform architecture. We emphasize the importance of distinguishing among benign entities such as cribriform changes and premalignant to malignant entities such as high-grade prostatic intraepithelial neoplasia, atypical intraductal cribriform proliferation, intraductal carcinoma of the prostate, and invasive adenocarcinoma (acinar and ductal types). The diagnostic criteria, differential diagnosis, and clinical implications of these cribriform lesions are discussed.

Data Sources.—

Literature review of pertinent publications in PubMed up to calendar year 2017. Photomicrographs obtained from cases at the University of California at Irvine and authors' collections.

Conclusions.—

Although relatively uncommon compared with small acinar lesions (microacinar carcinoma and small gland carcinoma mimickers), large cribriform lesions are increasingly recognized and have become clinically and pathologically important. The spectrum of cribriform lesions includes benign, premalignant, and malignant lesions, and differentiating them can often be subtle and difficult. Intraductal carcinoma of the prostate in particular is independently associated with worse prognosis, and its presence in isolation should prompt definitive treatment. Patients with atypical intraductal cribriform proliferation, intraductal carcinoma of the prostate, or even focal cribriform pattern of invasive adenocarcinoma in biopsies would not be ideal candidates for active surveillance because of the high risk of adverse pathologic findings associated with these entities.

Differential Diagnosis of Intraductal Lesions of the Prostate

The category of intraductal lesions of the prostate includes a range of primary prostatic and nonprostatic processes with wide variation in prognosis and recommended follow-up. Studies have shown that pathologists are uncomfortable with the diagnosis of these lesions and that the diagnostic reproducibility is low in this category. Despite the diagnostic difficulty, their accurate and reproducible diagnosis is critical for patient management. This review aims to highlight the diagnostic criteria, prognosis, and treatment implications of common intraductal lesions of the prostate. It focuses on the recognition of intraductal carcinoma of the prostate (IDC-P) in prostate needle biopsies and how to distinguish it from its common mimickers, including high-grade prostatic intraepithelial neoplasia, invasive cribriform prostatic adenocarcinoma, urothelial carcinoma extending into prostatic ducts, and prostatic ductal adenocarcinoma. IDC-P is independently associated with higher risk disease, and its identification in a needle biopsy, even in the absence of invasive carcinoma, should compel definitive treatment. Conversely, high-grade prostatic intraepithelial neoplasia has a much better prognosis and in limited quantities does not even warrant a repeat biopsy. IDC-P must be distinguished from urothelial carcinoma involving prostatic ducts, as recommended treatment varies markedly. Ductal adenocarcinoma may confuse the pathologist and clinician by overlapping terminology, and morphology may also mimic IDC-P on occasion. The use of ancillary testing with immunohistochemistry and molecular markers has also been reviewed.

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.

The update of prostatic ductal adenocarcinoma

Since initially described in 1967, prostatic ductal adenocarcinoma (PDA) has engendered a series of controversies on its origin, histological features, and biological behavior. Owing to the improvement of molecular biological technique, there are some updated findings on the characteristics of PDA. In the current review, we will mainly analyze its origin, clinical manifestations, morphological features, differential diagnosis, immunophenotype and molecular genetics, with the purpose of enhancing recognition of this tumor and making a correct diagnosis and treatment choice.

Intraductal Carcinoma of the Prostate: Morphologic Features, Differential Diagnoses, Significance, and Reporting Practices

The differential diagnosis for atypical cribriform lesions of the prostate has become increasingly complex and includes intraductal carcinoma of the prostate, high-grade prostatic intraepithelial neoplasia, and atypical intraductal proliferations. In this review, we summarize the morphologic and molecular features and significance of intraductal carcinoma of the prostate. We also summarize our institution's strategy for reporting and treatment recommendations for intraductal carcinoma of the prostate.

Ductal and Acinar Adenocarcinoma of Prostate: Morphological and Immunohistochemical Characterization

OBJECTIVES

We sought to characterize the ductal and acinar subtype of prostate adenocarcinoma using hematoxylin and eosin (H&E) staining and an immunohistochemical antibody cocktail. We also investigated the clinical features, prostate-specific antigen (PSA) levels, and biological aggressiveness of these tumors.

METHODS

We utilized tumor bearing prostate biopsies, obtained between 2010 and 2014 from Dow Diagnostic Research and Reference Laboratory, to identify cases of prostatic ductal and acinar adenocarcinoma using routine H&E and immunohistochemical staining. The immunohistochemical antibody cocktail 34βE12/p63/AMACR was used for staining. The association of clinicopathological variables including patient's age at diagnosis, Gleason score, and PSA levels before surgery was retrospectively analyzed.

RESULTS

A total of 10 ductal and 140 non-ductal cases were identified. Ductal cases were predominantly high grade with advanced histopathological features (90%; p=0.030). Marked elevation in PSA level was also reported in most cases. No other significant statistical difference was observed.

CONCLUSIONS

Pathological and immunohistochemical examination could be used to characterize ductal and acinar adenocarcinoma of the prostate. Ductal adenocarcinoma of the prostate is a rare subtype of prostate carcinoma and is be more likely to present with advanced grade cancer suggesting that timely detection of the disease is vital.

Diagnostic criteria for ductal adenocarcinoma of the prostate: interobserver variability among 20 expert uropathologists

AIMS

Ductal adenocarcinoma of the prostate (DAC) is clinically important, because its behaviour may differ from that of acinar adenocarcinoma. Our aims were to investigate the interobserver variability of this diagnosis among experts in uropathology and to define diagnostic criteria.

METHODS AND RESULTS

Photomicrographs of 21 carcinomas with ductal features were distributed among 20 genitourinary pathologists from eight countries. DAC was diagnosed by 18 observers (mean 13.2 cases, range 6-19). In 11 (52%) cases, a 2/3 consensus was reached for a diagnosis of DAC, and in five (24%) there was consensus against. In DAC, the respondents reported papillary architecture (86%), stratification of nuclei (82%), high-grade nuclear features (54%), tall columnar epithelium (53%), elongated nuclei (52%), cribriform architecture (40%), and necrosis (7%). The most important diagnostic feature reported for DAC was papillary architecture (59%), whereas nuclear and cellular features were considered to be most important in only 2-11% of cases. The most common differential diagnoses were intraductal prostate cancer (52%), high-grade PIN (37%), and acinar adenocarcinoma (17%). The most common reason for not diagnosing DAC was lack of typical architecture (33%).

CONCLUSIONS

Papillary architecture was the most useful diagnostic feature of DAC, and nuclear and cellular features were considered to be less important.

Preneoplasia in the prostate gland with emphasis on high grade prostatic intraepithelial neoplasia

There are a variety of morphological patterns and processes that have been implicated in the pathogenesis of prostate cancer. Prostatic intraepithelial neoplasia (PIN), inflammation with or without atrophy, and adenosis (atypical adenomatous hyperplasia) have all been given candidate status as precursor lesions of prostatic adenocarcinoma. Based on decades of research, high grade prostatic intraepithelial neoplasia (HPIN), a proliferative lesion of prostatic secretory cells, has emerged as the most likely morphological pre-invasive lesion involved in the evolution of many but not all prostatic adenocarcinomas. In this manuscript, we briefly discuss other proposed precursors of prostatic adenocarcinoma and then focus on the history, diagnostic criteria and morphology of HPIN. The incidence of HPIN and its relationship to prostate cancer is reviewed. The differential diagnosis of large glandular patterns in the prostate is discussed in depth. Finally, we summarise the recent clinicopathological studies evaluating the clinical significance of HPIN and discuss follow-up strategies in men diagnosed with HPIN.

An incidentally diagnosed prostatic ductal adenocarcinoma

Ductal adenocarcinoma of the prostate was initially described in 1967 by Melicow and Patcher. It was given the erroneous name endometrioid carcinoma, however, further studies confirmed the prostatic origin of this tumor. Currently DAP is classified as a histological variant of prostatic carcinoma. Compared with "classic" acinar carcinoma of the prostate, DAP is a rare histological finding. It's prevalence in prostatectomy and biopsy specimens varies from less than 1% for pure ductal adenocarcinoma up to 5% for mixed DAP. Because of its typical periurethral location, the tumor usually manifests itself clinically with urinary obstruction, urinary urgency, urinary frequency and hematuria. DAP is associated with more aggressive natural history and worse prognosis than pure AA - patients presented at more advanced stage, with poorly differentiated and distant disease. DAP has a tendency to spread to regional lymph nodes, axial skeleton, and visceral organs. We report a case of a 90-year old man who presented to our clinic with acute urinary retention and gross hematuria. He underwent suprapubic transvesical adenomectomy to diminish the urinary obstruction. The pathological examination of the specimens revealed a dominant focus of DAP, which was located near the intraprostatic urethra and a coexisting, smaller component of "classic" acinar adenocarcinoma.

Histopathological features of ductal adenocarcinoma of the prostate in 1,051 radical prostatectomy specimens

Ductal adenocarcinoma (DAC) of the prostate is thought to have worse prognosis than prostatic acinar carcinoma (PAC). We aimed to evaluate the prognostic significance of histopathological patterns of DAC. A series of 1,051 radical prostatectomy specimens from Karolinska University Hospital 1998-2005 was reviewed. A ductal component was classified as classical DAC (DACC) if it had columnar, pseudostratified epithelium, elongated nuclei, and papillary, glandular, or cribriform architecture; borderline DAC (DACB) if it lacked elongated nuclei or classical architecture; and prostatic adenocarcinoma with ductal features (PCDF) if stratified high-grade nuclei were found. DACC, DACB, and PCDF were seen in 2.6, 4.0, and 1.6 % of the cases. DAC was usually mixed with PAC and constituted 10-100 % (mean 40 %) of the main tumor. Location was periurethral, peripheral, or both in 69.8, 3.5, and 26.7 %. Necrosis was seen in 31.3 %, stromal invasion of DAC in 52.3 %, and intraductal spread in 91.9 %. In DACC/DACB and PAC, extraprostatic extension was seen in 66.7 and 42.4 % (p < 0.001) and seminal vesicle invasion in 13.0 and 5.0 % (p = 0.0045). DACC, DACB, and PCDF had a hazard ratio for biochemical recurrence of 1.5 (0.7-2.8), 1.4 (0.8-2.6) and 1.2 (0.5-2.7). When PCDF was excluded from DAC, hazard ratio was 1.4 (95 % CI 0.9-2.3, p = 0.12). Location, % DAC, necrosis, stromal invasion, or Gleason score were not predictive of recurrence. This suggests that DACC and DACB are more aggressive than average PAC, while cancers with acinar architecture and pseudostratified high-grade nuclei should not be included in DAC.

Variants and unusual patterns of prostate cancer: clinicopathologic and differential diagnostic considerations

Beyond the typical acinar morphology observed in the majority of prostatic adenocarcinomas, a spectrum of morphologic variants and prostate cancer subtypes exists. These unusual entities may be classified as: (1) cancer morphologies arising by divergent differentiation of prostatic ductal, acinar, or basal cells and associated with unique clinical features and/or therapeutic approaches, and (2) histologies occurring in the context of usual prostatic adenocarcinoma that may result in diagnostic misinterpretation or difficulties in Gleason grade assignment, especially in limited samples. This article details a number of variants, with emphasis on diagnostic criteria, differential diagnoses, and clinical significance.

Improved differentiation between ductal and acinar prostate cancer using three-dimensional histology and biomarkers

OBJECTIVE

The aim of the study was to refine the methodology for discriminating the ductal (DAP) and acinar adenocarcinomas (AAP) of the prostate and confirm that prostate carcinoma of ductal origin is a more aggressive subtype.

MATERIAL AND METHODS

A retrospective analysis of 110 consecutive radical prostatectomy cases operated on between 2000 and 2006 and worked up using large-format "two-dimensional" (2D; 4 μm thick) and "three-dimensional" (3D; 1500 μm thick) histology sections was carried out, with an average follow-up of 5.1 years. The same material was also analysed for selected biomarkers in tissue microarray blocks. The most discriminatory biomarkers were then tested on preoperative core biopsy specimens from 24 of these patients.

RESULTS

3D histology classified 97/110 (88%) cases of AAP and 13/110 (12%) DAP, which was then confirmed in 2D specimens. The DAP cases had a significantly greater frequency of pT3a and more advanced cancers, > 20 mm tumour focus, high-grade prostatic intraepithelial neoplasia, Gleason score ≥ 7, positive margin, extracapsular extension, vascular invasion, seminal vesicle infiltration, biochemical/local recurrence, regional lymph-node metastases and distant metastases. Three biomarkers in combination (chromogranin A, epidermal growth factor receptor and p53] distinguished DAP from AAP with an accuracy of 94% (area under the curve 0.94, 95% confidence interval 0.88-0.99). The same high accuracy was achieved using these three biomarkers on the preoperative specimens.

CONCLUSIONS

Both 3D histology and the three selected biomarkers can help in accurately distinguishing DAP from AAP. The clear-cut distinction of two forms of prostate cancers by the approach advocated in this paper would allow AAP patients to undergo less radical treatment and would segregate DAP patients into a subset requiring more effective treatment regimens.

Immunohistochemical verification of ductal differentiation in prostate cancer

Recent studies have shown that patients with prostate carcinomas exhibiting ductal differentiation have an unfavourable prognosis compared with those with purely acinar adenocarcinomas. We studied the expression of nine immunohistochemical markers to evaluate their value in delineating carcinomas with and without ductal differentiation. Thirteen tumours showing cellular characteristics and growth patterns typical of ductal differentiation were identified among 110 analysed prostatectomy specimens. The levels of cytoplasmic expression of chromogranine A (69% vs 19%, p = 0.0003) and nuclear expression of p53 (76% vs 12%, p < 0.0001) as well as nuclear expression of Ki-67 (69% vs 26%, p = 0.0047) in the tumour cells, were found to be statistically significantly different in the two tumour categories. Assessment of chromogranine A, p53 and Ki-67 in prostate carcinoma may serve as useful adjunctive diagnostic tools for delineating more aggressive prostate cancer cases exhibiting ductal differentiation.

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

OBJECTIVE

To use the national Surveillance, Epidemiology, and End Results (SEER) cancer registry to describe the natural history, national incidence and treatment patterns for ductal prostate cancer (PCa) over the last 20 years, as the available literature on ductal PCa is limited to small case series because of few patient numbers.

PATIENTS AND METHODS

From the SEER registry, 693 men with ductal PCa were identified from 1970. The demographics, clinical features and cause of death data were collected from men with ductal and acinar histological types.

RESULTS

The incidence of ductal PCa has increased over each decade, but the overall percentage of ductal relative to acinar PCa has remained stable. Men with ductal PCa were more likely to present with advanced disease (30% T3 with ductal PCa, compared with 7% with acinar PCa). Men with ductal PCa underwent similar rates of radical surgery, lower rates of radiotherapy but a higher frequency of outlet (transurethral resection) procedures. Men with ductal PCa had a significantly greater rate of death from PCa (12% vs 4%) than men with acinar PCa. Comparing PCa-specific mortality, men with ductal PCa had similar rates of death to men with Gleason 4 + 4 grade acinar PCa.

CONCLUSIONS

Despite a stable incidence, ductal PCa remains an aggressive PCa usually presenting with advanced clinical stage and resulting in a high rate of PCa-specific mortality similar to Gleason 4 + 4 acinar PCa. Patients would probably benefit from combined modalities including radical surgery, radiotherapy and palliative outlet procedures.

Pathologic stage of prostatic ductal adenocarcinoma at radical prostatectomy: effect of percentage of the ductal component and associated grade of acinar adenocarcinoma

It is unknown whether ductal adenocarcinomas are more aggressive when matched for Gleason score (assigning the ductal component as Gleason pattern 4). Moreover, little is known whether a certain percentage of the ductal component is needed to account for its more aggressive behavior. Of 18,552 radical prostatectomies performed from 1995 to 2008, 93 cases with a ductal adenocarcinoma component were identified. Cases were classified based on their ductal/acinar ratio (<10%; ≥10% and <50%; ≥50%). There was no difference in the distribution of Gleason score 3+4=7 versus 4+3=7 between ductal and nonductal tumors, such that cases were combined as Gleason score 7. There was no age, race, and serum prostate-specific antigen difference between patients with and without ductal adenocarcinoma. Cases with ductal adenocarcinoma were less likely to be organ confined (36.6% vs 65.6%) and more likely to show seminal vesicle invasion (SVI) (19.3% vs 5.3%), P<0.0001. There was no difference in lymph node metastases or positive margins between cases with and without ductal features. An increasing percentage of the ductal component correlated with an increased risk of extraprostatic extension (P=0.04) and SVI (P<0.0001). To account for overall different Gleason scores between ductal and nonductal cases, and the effect of differing percentages of ductal features as well, the following analysis was carried out. For Gleason score 7 cases and ≥10% ductal differentiation, cases with ductal features were more likely to have nonfocal extraprostatic extension (64.0%) versus cases without ductal features (34.7%), P=0.002. In this group, there was no statistically significant difference in SVI or lymph node involvement between Gleason score 7 ductal and nonductal tumors. For Gleason score 7 cases with <10% ductal features, there was no difference in pathologic stage versus nonductal cases. There was no difference in pathologic stage between ductal and nonductal cases for Gleason score 8 to 10 cases, regardless of the percentage of the ductal component. This study shows that ductal adenocarcinoma admixed with Gleason pattern 3 is more aggressive than Gleason score 7 acinar cancer, as long as the ductal component is ≥10%. In cases with a very minor ductal component, these differences are lost. In addition, Gleason score 8 to 10 tumors with ductal features are not significantly more aggressive that acinar Gleason score 8 to 10 cancers in which the pure high-grade tumor, regardless of ductal features, determines the behavior.