Optimizing the diagnosis and management of ductal prostate cancer

Prostate ductal adenocarcinoma exhibiting a late recurrence in the anterior urethra 13 years post-total prostatectomy: a case report

BACKGROUND

Prostate ductal adenocarcinoma, a rare histology observed in 0.4-0.8% of all prostate cancers, is treated similarly to acinar adenocarcinoma but tends to have a higher likelihood of metastasis, recurrence, and poorer prognosis.

CASE PRESENTATION

A 73-year-old Asian-Japanese male presented with gross hematuria, with investigations revealing a prostate ductal adenocarcinoma. Subsequent radical prostatectomy indicated a Gleason score of 8 with no lymph node metastasis. Despite initial prostate-specific antigen level reductions post-prostatectomy and salvage radiation therapy due to recurring elevated prostate-specific antigen levels, no recurrence was evident until 13 years later. A tumor in the anterior urethra was identified as metastasis of his prostate ductal adenocarcinoma.

CONCLUSION

This report presents an uncommon case of prostate ductal adenocarcinoma exhibiting a late recurrence in the anterior urethra 13 years post-radical prostatectomy.

68Ga-PSMA PET/CT and 18F-FDG PET/CT in the diagnosis of prostatic ductal cancer

PURPOSES

To explore the characteristics of PSMA PET/CT and FDG PET/CT images in prostatic ductal adenocarcinoma (DA) patients.

METHODS

We retrospectively enrolled prostatic DA patients with PET/CT scans at Tongji Hospital from 2018 to 2022. Patients with prostatic acinar adenocarcinoma (AA) and benign pathology (BP) were enrolled by 1:1 matching. Differences in the uptake of primary and metastatic foci on PET among the groups were analyzed.

RESULTS

A total of 42 patients were enrolled: 14 in each group. In primary foci, the mean PSMA uptake in the DA group was lower than that in the AA group (14.2 ± 9.6 vs. 27.1 ± 14.3, P = 0.009) and greater than that in the BP group (14.2 ± 9.6 vs. 4.7 ± 1.3, P = 0.003). The AUCs of the DA-AA ROC curve and DA-BP ROC curve were 0.781 and 0.872, respectively. The median PSMA uptake of metastatic lymph nodes in the DA group was lower than that in the AA group (5.6 vs. 14.2, P = 0.033), with no significant difference in metastatic bone lesions (9.5 vs 19.1, P = 0.485). No significant difference was found in the FDG uptake of primary and metastatic foci between the DA and AA groups (P > 0.05).

CONCLUSION

Prostatic DA has greater PSMA uptake than BP diseases, but lower uptake in both primary foci and metastatic lymph nodes than AA on PSMA PET/CT, aiding in the differential diagnosis of DA, AA and BP diseases. Clinicians should combine traditional imaging with PSMA PET/CT to avoid underestimating the clinical stage of DA patients.

Feasibility study of ADCs targeting TROP-2, HER2, and CD46 in Ductal Adenocarcinoma and Intraductal Carcinoma of the prostate

BACKGROUND

Ductal Adenocarcinoma (DAC) and Intraductal Carcinoma of the Prostate (IDC-P) respond poorly to all the currently available conventional therapies. Given their accurate and efficient elimination of cancer cells, Antibody-Drug Conjugates (ADCs) have become one of the most promising anticancer treatments. However, no ADCs have so far been approved for Prostate Cancer (PCa) treatment. This study investigated TROP-2, HER2, and CD46 expression in DAC/IDC-P samples, indirectly analyzing their preliminary feasibility as therapeutic targets for future treatment of the two conditions.

PATIENTS AND METHODS

We conducted a retrospective study involving 184 participants (87 DAC/IDC-P patients and 97 Prostatic Acinar Adenocarcinoma (PAC) patients with a Gleason score ≥ 8) without prior treatment between August 2017 and August 2022. Immunohistochemical staining was employed to detect the differential protein expressions of TROP-2, HER2, and CD46 in DAC/IDC-P, PAC, and normal prostate tissues.

RESULTS

Compared to pure PAC tissues, TROP-2 expression was significantly higher in DAC/IDC-P and DAC/IDC-P-adjacent PAC tissues (H-score 68.8 vs. 43.8, p < 0.001, and 59.8 vs. 43.8, p = 0.022, respectively). No significant differences in HER2 expression were observed across different cancer tissues. Compared to both DAC/IDC-P-adjacent PAC and pure PAC tissues, CD46 expression was significantly higher in DAC/IDC-P tissues (42.3 vs. 28.6, p = 0.041, and 42.3 vs. 24.3, p = 0.0035, respectively).

CONCLUSIONS

Herein, TROP-2 and CD46 expression was higher in DAC/IDC-P tissues than in pure PAC and normal prostate tissues. This finding implies that ADCs targeting the two proteins hold significant promise as potential future treatments for DAC/IDC-P.

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.

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.

The therapeutic efficacy of radical prostatectomy and external beam radiation therapy in patients with different pathological patterns of prostate cancer

BACKGROUND

We aim to investigate the prognostic value of different pathological patterns of non-adenocarcinoma prostate cancers (PCa) in radical prostatectomy (RP) and external beam radiation therapy (EBRT).

METHODS

Data of 470,258 localized PCa patients between 2004 and 2016 were collected from the Surveillance, Epidemiology, and End Results database. Propensity score matching was performed to balance the baseline characteristics of patients in different groups. Kaplan-Meier curves and Cox regression were used for survival analysis. Overall survival (OS) and cancer-specific survival (CSS) were set as endpoints.

RESULTS

Totally, 1044 patients with non-adenocarcinoma patterns of PCa were included. Patients with small cell neuroendocrine carcinoma (SCNC) and neuroendocrine differentiation (NED) harbored the worst prognosis in both RP and EBRT among all pathological groups. RP exhibited superior effects to EBRT for this group of cases. Ductal carcinoma (DA) was also related to poorer survival outcomes versus PAC in both local therapies. Yet, for men with DA, both RP and EBRT still improved patients' prognosis against no local therapy (NLT), with RP being the superior modality. Cases harboring mucinous adenocarcinoma (MA) and signet ring cell carcinoma (SRCC) shared comparable clinical outcomes to men with PAC. However, for cases with MA, neither RP nor EBRT was related to better survival outcomes against NLT, while for patients with SRCC, both RP and EBRT prolonged patients' survival with similar effects.

CONCLUSIONS

Our study provided a comprehensive view of the treatment effect of RP and EBRT in non-adenocarcinoma PCa patients. These findings could facilitate clinicians in making therapeutic decision-making for non-adenocarcinoma patients.

Prostate-Specific Membrane Antigen Uptake Heterogeneity in Mixed Ductal-Acinar Adenocarcinoma of the Prostate

ABSTRACT

Prostate-specific membrane antigen (PSMA) PET findings of mixed ductal-acinar adenocarcinoma of the prostate are rarely reported. We describe 18F-PSMA-1007 PET/CT and delayed pelvic 18F-PSMA-1007 PET/MRI findings in a case of prostatic mixed ductal-acinar adenocarcinoma with multiple lymph node and bone metastases. The primary tumor showed heterogeneous PSMA uptake. The metastases in the right ilium and acetabulum showed intense PSMA uptake, but the pelvic lymph node and left iliac bone metastases showed no significant PSMA uptake. Knowledge of the intraprimary and intermetastatic heterogeneity of PSMA uptake in mixed ductal-acinar adenocarcinoma of the prostate may be helpful for accurate interpretation.

Uncovering the Secrets of Prostate Cancer's Radiotherapy Resistance: Advances in Mechanism Research

Prostate cancer (PCa) is a critical global public health issue with its incidence on the rise. Radiation therapy holds a primary role in PCa treatment; however, radiation resistance has become increasingly challenging as we uncover more about PCa's pathogenesis. Our review aims to investigate the multifaceted mechanisms underlying radiation therapy resistance in PCa. Specifically, we will examine how various factors, such as cell cycle regulation, DNA damage repair, hypoxic conditions, oxidative stress, testosterone levels, epithelial-mesenchymal transition, and tumor stem cells, contribute to radiation therapy resistance. By exploring these mechanisms, we hope to offer new insights and directions towards overcoming the challenges of radiation therapy resistance in PCa. This can also provide a theoretical basis for the clinical application of novel ultra-high-dose-rate (FLASH) radiotherapy in the era of PCa.

Macrocystic ductal adenocarcinoma, a good outcome for a rare cancer in an elderly comorbid patient

Ductal adenocarcinoma is an aggressive prostate cancer often presenting late due to low serum PSA. A variant presentation of ductal adenocarcinoma occurs with formation of large cystic structures in the prostate, often associated with lower urinary tract symptoms. We present a case illustrating investigation and successful management of a macrocytic ductal carcinoma in a 90 year old patient.

Novel biomarkers predict prognosis and drug-induced neuroendocrine differentiation in patients with prostate cancer

Background

A huge focus is being placed on the development of novel signatures in the form of new combinatorial regimens to distinguish the neuroendocrine (NE) characteristics from castration resistant prostate cancer (CRPC) timely and accurately, as well as predict the disease-free survival (DFS) and progression-free survival (PFS) of prostate cancer (PCa) patients.

Methods

Single cell data of 4 normal samples, 3 CRPC samples and 3 CRPC-NE samples were obtained from GEO database, and CellChatDB was used for potential intercellular communication, Secondly, using the "limma" package (v3.52.0), we obtained the differential expressed genes between CRPC and CRPC-NE both in single-cell RNA seq and bulk RNA seq samples, and discovered 12 differential genes characterized by CRPC-NE. Then, on the one hand, the diagnosis model of CRPC-NE is developed by random forest algorithm and artificial neural network (ANN) through Cbioportal database; On the other hand, using the data in Cbioportal and GEO database, the DFS and PFS prognostic model of PCa was established and verified through univariate Cox analysis, least absolute shrinkage and selection operator (Lasso) regression and multivariate Cox regression in R software. Finally, somatic mutation and immune infiltration were also discussed.

Results

Our research shows that there exists specific intercellular communication in classified clusters. Secondly, a CRPC-NE diagnostic model of six genes (HMGN2, MLLT11, SOX4, PCSK1N, RGS16 and PTMA) has been established and verified, the area under the ROC curve (AUC) is as high as 0.952 (95% CI: 0.882-0.994). The mutation landscape shows that these six genes are rarely mutated in the CRPC and NEPC samples. In addition, NE-DFS signature (STMN1 and PCSK1N) and NE-PFS signature (STMN1, UBE2S and HMGN2) are good predictors of DFS and PFS in PCa patients and better than other clinical features. Lastly, the infiltration levels of plasma cells, T cells CD4 naive, Eosinophils and Monocytes were significantly different between the CRPC and NEPC groups.

Conclusions

This study revealed the heterogeneity between CRPC and CRPC-NE from different perspectives, and developed a reliable diagnostic model of CRPC-NE and robust prognostic models for PCa.

Using PSMA imaging for prognostication in localized and advanced prostate cancer

The use of prostate-specific membrane antigen (PSMA)-directed applications in modern prostate cancer management has evolved rapidly over the past few years, helping to establish new treatment pathways and provide further insights into prostate cancer biology. However, the prognostic implications of PSMA-PET have not been studied systematically, owing to rapid clinical implementation without long follow-up periods to determine intermediate-term and long-term oncological outcomes. Currently available data suggest that traditional prognostic factors and survival outcomes are associated with high PSMA expression (both according to immunohistochemistry and PET uptake) in men with localized and biochemically recurrent disease. Treatment with curative intent (primary and/or salvage) often fails when PSMA-positive metastases are present; however, the sensitivity of PSMA-PET in detecting all metastases is poor. Low PSMA-PET uptake in recurrent disease is a favourable prognostic factor; however, it can be associated with poor prognosis in conjunction with high ¹⁸F-fluorodeoxyglucose uptake in metastatic castration-resistant prostate cancer. Clinical trials embedding PSMA-PET for guiding management with reliable oncological outcomes are needed to support ongoing clinical use.

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.

Multi-Omics Analysis Reveals Clinical Value and Possible Mechanisms of ATAD1 Down-Regulation in Human Prostate Adenocarcinoma

Prostate adenocarcinoma (PRAD) is the most common histological subtype of prostate cancer. Post-treatment biochemical recurrence is a challenging issue. ATAD1 (ATPase Family AAA Domain Containing 1) plays a vital role in mitochondrial proteostasis and apoptosis activity, while its clinical value in PRAD and its impact on the tumor microenvironment (TME) remain unanswered. In this study, we aimed to investigate the clinical value and possible mechanisms of ATAD1 in PRAD via multi-omics analysis. Using cBioPortal, we confirmed that ATAD1 alteration was associated with gene expression and unfavorable DFS. Deep deletion predominantly occurred in PRAD. By integrating DriverDBv3 and GEPIA2, we noted ATAD1 downregulation in PRAD tissues compared to normal tissues, associated with unfavorable DFS in PRAD patients. DNA repair genes ATM, PARP1and BRCA2 had positive associations with ATAD1 expression. We found that the generalization value of ATAD1 could be applied to other cancers such as KIRC and UCEC. In addition, LinkedOmics identified that the functional involvement of ATAD1 participates in mitochondrial structure and cell cycle progression. Using TIMER analysis, we demonstrated that ATAD1 downregulation correlated with an immunosuppressive TME. Furthermore, we accessed a GSE55062 dataset on UALCAN and discovered the involvement of ERG-mediated transcriptional repression on ATAD1 downregulation. Cross-association screening of shATAD1 efficacy vs. altered mRNAs identified 190 perturbed mRNAs. Then, functional enrichment analysis using the Metascape omics tool recognized that shATAD1-perturbed mRNAs are primarily in charge of the activation of Wnt/β-catenin pathway and lipid metabolic processes. In conclusion, multi-omics results reveal that ATAD1 downregulation is a clinical biomarker for pathological diagnosis and prognosis for patients with PRAD. Reduced ATAD1 may be involved in the enhanced activity of mitochondria and cell cycle, as well as possibly shaping an immunosuppressive TME. ERG serves as an upstream transcriptional repressor of ATAD1. Downstream mechanisms of ATAD1 are involved in Wnt/β-catenin pathway and lipid metabolic processes.

68 Ga-PSMA-11 and 18 F-FDG PET/CT in a Case of Ductal Adenocarcinoma of the Prostate

ABSTRACT

Prostatic ductal adenocarcinoma is an uncommon variant of prostatic carcinoma with aggressive behavior and worse prognosis. We describe 68 Ga-PSMA-11 and FDG PET/CT findings in a case of prostatic ductal adenocarcinoma with pelvic lymph node metastases. The majority of the prostate tumor and all the metastatic lesions showed no significant PSMA uptake but intense FDG uptake. The role of PSMA and FDG PET in the management of prostatic ductal adenocarcinoma needs to be investigated in a large number of patients.

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.

Roles of m5C RNA Modification Patterns in Biochemical Recurrence and Tumor Microenvironment Characterization of Prostate Adenocarcinoma

Background

Prostate cancer is the second most common cancer with a high risk of biochemical recurrence (BCR) among men. Recently, 5-methylcytosine (m5C) modification has attracted more attention as a new layer of RNA post-transcriptional regulation. Hence, we aimed at investigating the potential roles of m5C modification regulators in the BCR of prostate adenocarcinoma (PRAD).

Methods

CNV data, mutation annotation data, mRNA expression profiles, and clinical data were downloaded from TCGA and GEO databases. Kaplan-Meier curves analysis, log-rank test, univariate and multivariate Cox regression, and time-dependent ROC curves analysis were performed to evaluate the prognostic factors. Principal components analysis (PCA) was applied to validate the distinction between subgroups. Gene set variation analysis (GSVA) was used to investigate the underlying pathways associated with m5C modification patterns. Single sample gene set enrichment analysis (ssGSEA) was utilized to assess the infiltration of distinct immune cells. Tumor Immune Dysfunction and Exclusion (TIDE) prediction was carried out to assess the potential response to immune checkpoint blockade (ICB) therapy. The m5C modification signature was constructed via LASSO Cox's proportional hazards regression method.

Results

After comprehensively analyzing various types of data from TCGA dataset, and exploring the differential expression and prognostic value of each m5C regulator, we identified m5C modification patterns based on 17 m5C regulators. Two patterns presented a significant difference in the risk of BCR, the tumor microenvironment (TME), and immunotherapy response in PRAD. We found that TET2, which was highly expressed in adjacent normal tissues compared to tumor tissues, was closely associated with many infiltrating immune cells. The m5C modification signature was constructed for the clinical application. Risk score calculated by m5C signature was associated with T stage, N stage, Gleason score, and the possibility of BCR (HR, 4.197; 95% CI, 3.016-5.842; p < 0.001). A higher risk score also represented the possibility of immunotherapy response. Finally, the potential roles of m5C modification signature were validated in the testing dataset.

Conclusions

Our study revealed the potential roles of m5C modification in the PRAD BCR and TME diversity, which may provide new insight into the field of prostate cancer in future research.

Defining Diagnostic Criteria for Prostatic Ductal Adenocarcinoma at Multiparametric MRI

Background Prostatic ductal adenocarcinoma (DAC) is an aggressive histologic variant of prostate cancer that often warrants multimodal therapy and poses a significant diagnostic challenge clinically and at imaging. Purpose To develop multiparametric MRI criteria to define DAC and to assess their diagnostic performance in differentiating DAC from prostatic acinar adenocarcinoma (PAC). Materials and Methods Men with histologically proven DAC who had multiparametric MRI before radical prostatectomy were retrospectively identified from January 2011 through November 2018. MRI features were predefined using a subset of nine DACs and then compared for men with peripheral-zone DACs 1 cm or greater in size and men with matched biopsy-confirmed International Society of Urological Pathology grade group 4-5 PAC, by four independent radiologists blinded to the pathologic diagnosis. Diagnostic performance was determined by consensus read. Patient and tumor characteristics were compared by using the Fisher test, t-tests, and Mann-Whitney U test. Agreement (Cohen κ) and sensitivity analyses were also performed. Results There were 59 men with DAC (median age, 63 years [interquartile range, 56, 67 years]) and 59 men with PAC (median age, 64 years [interquartile range, 59, 69 years]). Predefined MRI features, including intermediate T2 signal, well-defined margin, lobulation, and hypointense rim, were detected in a higher proportion of DACs than PACs (76% [45 of 59] vs 5% [three of 59]; P < .001). On consensus reading, the presence of three or more features demonstrated 76% sensitivity, 94% specificity, 94% positive predictive value [PPV], and 80% negative predictive value [NPV] for all DACs and 100% sensitivity, 95% specificity, 81% PPV, and 100% NPV for pure DACs. The DACs and PACs showed no difference in contrast enhancement (100% vs 100%; P >.99, median T2 signal intensity (254 vs 230; P = .99), or apparent diffusion coefficient (median, 677 10^-6 mm²/sec vs 685 10^-6 mm²/sec; P = .73). Conclusion The presence of intermediate T2 signal, well-defined margin, lobulation, and/or hypointense rim, together with restricted diffusion and contrast enhancement at multiparametric MRI of the prostate, suggests prostatic ductal adenocarcinoma rather than prostatic acinar adenocarcinoma. © RSNA, 2022 Online supplemental material is available for this article.

Hidden clues in prostate cancer - Lessons learned from clinical and pre-clinical approaches on diagnosis and risk stratification

The heterogeneity of prostate cancer is evident at clinical, morphological and molecular levels. To aid clinical decision making, a three-tiered system for risk stratification is used to designate low-, intermediate-, and high-risk of disease progression. Intermediate-risk prostate cancers are the most frequently diagnosed, and even with common diagnostic features, can exhibit vastly different clinical progression. Thus, improved risk stratification methods are needed to better predict patient outcomes. Here, we provide an overview of the improvements in diagnosis/prognosis arising from advances in pathology reporting of prostate cancer, which can improve risk stratification, especially for patients with intermediate-risk disease. This review discusses updates to pathology reporting of morphological growth patterns, and proposes the utility of integrating prognostic biomarkers or innovative imaging techniques to enhance clinical decision-making. To complement clinical studies, experimental approaches using patient-derived tumors have highlighted important cellular and morphological features associated with aggressive disease that may impact treatment response. The intersection of urology, pathology and scientific disciplines is required to work towards a common goal of understanding disease pathogenesis, improving the stratification of patients with intermediate-risk disease and subsequently defining optimal treatment strategies using precision-based approaches.

Genomic Features and Clinical Implications of Intraductal Carcinoma of the Prostate

Intraductal carcinoma of the prostate (IDC-P) is a rare and unique form of aggressive prostate carcinoma, which is characterized by an expansile proliferation of malignant prostatic epithelial cells within prostatic ducts or acini and the preservation of basal cell layers around the involved glands. The vast majority of IDC-P tumors result from adjacent high-grade invasive cancer via the retrograde spreading of tumor cells into normal prostatic ducts or acini. A subset of IDC-P tumors is rarely derived from the de novo intraductal proliferation of premalignant cells. The presence of IDC-P in biopsy or surgical specimens is significantly associated with aggressive pathologic features, such as high Gleason grade, large tumor volume, and advanced tumor stage, and with poor clinical courses, including earlier biochemical recurrence, distant metastasis, and worse survival outcomes. These architectural and behavioral features of IDC-P may be driven by specific molecular properties. Notably, IDC-P possesses distinct genomic profiles, including higher rates of TMPRSS2–ERG gene fusions and PTEN loss, increased percentage of genomic instability, and higher prevalence of germline BRCA2 mutations. Considering that IDC-P tumors are usually resistant to conventional therapies for prostate cancer, further studies should be performed to develop optimal therapeutic strategies based on distinct genomic features, such as treatment with immune checkpoint blockades or poly (adenosine diphosphate–ribose) polymerase inhibitors for patients harboring increased genomic instability or BRCA2 mutations, as well as genetic counseling with genetic testing. Patient-derived xenografts and tumor organoid models can be the promising in vitro platforms for investigating the molecular features of IDC-P tumor.