Ductal and Acinar Adenocarcinoma of Prostate: Morphological and Immunohistochemical Characterization

Novel Association of RAD54L Mutation with Müllerian Clear Cell Carcinoma of the Male Urethra: New Insights Regarding the Molecular Mechanisms of a Rare Tumour

INTRODUCTION

Müllerian clear cell carcinoma of the male urethra is similar to that of the female genital tract in terms of morphology and immunohistochemical expression but is rarely observed in clinical practice.

CASE PRESENTATION

Here, we report the case of a 65-year-old man diagnosed with Müllerian clear cell carcinoma who harboured a mutation in RAD54L. This patient was diagnosed by electrocautery and ultimately underwent prostatectomy. After a six-month follow-up period, no signs of recurrence or additional malignancy were found. Based on our analysis of the available literature, it appears that Müllerian clear cell carcinoma with RAD54L mutation has not been reported until now.

CONCLUSION

This case enhances our knowledge of the molecular biology of Müllerian clear cell carcinoma of the male urethra, which will help clinicians select optimal treatment options for this rare cancer in patients with specific driver mutations.

Unraveling the Mysteries of Perineural Invasion in Benign and Malignant Conditions

Perineural invasion (PNI) is defined as the dissemination of neoplastic cells within the perineural space. PNI can be a strong indicator of malignancy and is linked to poor prognosis and adverse outcomes in various malignant neoplasms; nevertheless, it can also be seen in benign pathologic conditions. In this review article, we discuss various signaling pathways and neurotrophic factors implicated in the development and progression of PNI. We also describe the methodology, benefits, and limitations of different in vitro, ex vivo, and in vivo models of PNI. The spectrum of presentation for PNI can range from diffuse spread within large nerves ("named" nerves) all the way through localized spread into unnamed microscopic nerves. Therefore, the clinical significance of PNI is related to its extent rather than its mere presence or absence. In this article, we discuss the guidelines for the identification and quantification of PNI in different malignant neoplasms based on the College of American Pathologists (CAP) and World Health Organization (WHO) recommendations. We also describe benign pathologic conditions and neoplasms demonstrating PNI and potential mimics of PNI. Finally, we explore avenues for the future development of targeted therapy options via modulation of signaling pathways involved in PNI.

Combinatorial approaches of nanotherapeutics for inflammatory pathway targeted therapy of prostate cancer

Prostate cancer (PC) is the most prevalent male urogenital cancer worldwide. PC patients presenting an advanced or metastatic cancer succumb to the disease, even after therapeutic interventions including radiotherapy, surgery, androgen deprivation therapy (ADT), and chemotherapy. One of the hallmarks of PC is evading immune surveillance and chronic inflammation, which is a major challenge towards designing effective therapeutic formulations against PC. Chronic inflammation in PC is often characterized by tumor microenvironment alterations, epithelial-mesenchymal transition and extracellular matrix modifications. The inflammatory events are modulated by reactive nitrogen and oxygen species, inflammatory cytokines and chemokines. Major signaling pathways in PC includes androgen receptor, PI3K and NF-κB pathways and targeting these inter-linked pathways poses a major therapeutic challenge. Notably, many conventional treatments are clinically unsuccessful, due to lack of targetability and poor bioavailability of the therapeutics, untoward toxicity and multidrug resistance. The past decade witnessed an advancement of nanotechnology as an excellent therapeutic paradigm for PC therapy. Modern nanovectorization strategies such as stimuli-responsive and active PC targeting carriers offer controlled release patterns and superior anti-cancer effects. The current review initially describes the classification, inflammatory triggers and major inflammatory pathways of PC, various PC treatment strategies and their limitations. Subsequently, recent advancement in combinatorial nanotherapeutic approaches, which target PC inflammatory pathways, and the mechanism of action are discussed. Besides, the current clinical status and prospects of PC homing nanovectorization, and major challenges to be addressed towards the advancement PC therapy are also addressed.

Cribriform pattern disease over-represented in pelvic lymph node metastases identified on 68GA PSMA-PET/CT

Objectives

To determine whether any specific histologic subtype of prostate cancer was preferentially represented in pelvic lymph node metastases identified on 68GA-PSMA-PET/CT.

Subjects and Methods

A consecutive series of 66 men with biochemical recurrent prostate cancer was evaluated with 68GA-PSMA-PET/CT. Where disease was confined to pelvic lymph nodes, patients were offered salvage extended pelvic lymph node dissection. Twenty patients ultimately proceeded to extended bilateral template pelvic lymph node dissection. Lymph node positivity and the histologic subtype of apparent cancer were assessed, as was PSA response to this intervention.

Results

Mean PSA at time of PSMA scanning for patients undergoing lymphadenectomy was 2.49 (n = 20, range 0.21-12.0). In 16 of 20 patients, there was evidence of metastatic cribriform pattern prostate cancer in excised nodes (100% cribriform pattern in 11/16). Only four of 20 patients had no evidence of this histologic subtype of disease. PSA response was not related to the presence or proportional amount of cribriform pattern disease identified.

Conclusions

Cribriform pattern adenocarcinoma appears to be the histologic subtype preferentially identified in pelvic lymph nodes on 68GA-PSMA-PET/CT. The use of PSMA-PET may be particularly valuable in staging of primary or biochemically recurrent prostate cancer in patients with cribriform pattern disease detected on initial biopsy or radical prostatectomy. Further research is required to further confirm the observed association.

Immunotherapy for Metastatic Prostate Cancer: Current and Emerging Treatment Options

The advent of immunotherapy has revolutionized cancer treatment. Prostate cancer has an immunosuppressive microenvironment and a low tumor mutation burden, resulting in low neoantigen expression. The consensus was that immunotherapy would be less effective in prostate cancer. However, recent studies have reported that prostate cancer does have a high number of DNA damage and repair gene defects. Immunotherapies that have been tested in prostate cancer so far have been mainly vaccines and checkpoint inhibitors. A combination of genomically targeted therapies, with approaches to alleviate immune response and thereby make the tumor microenvironment immunologically hot, is promising.

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

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

Ductal variant of prostate adenocarcinoma harbor Xenotropic murine leukemia virus related virus (XMRV) infection: a novel finding in subtype of prostate cancer

OBJECTIVE

Xenotropic murine leukemia virus related virus (XMRV), is the first gammaretrovirus identified a decade ago, in human tissue bearing adenocarcinoma of prostate, followed by several researches documenting little or no prevalence of XMRV in prostate cancer samples. However, the status of XMRV within subtype of prostate adenocarcinoma has not been investigated yet. In this study, we investigated the relationship between XMRV and broad spectrum morphological entities of prostate adenocarcinoma, including acinar, ductal and other rare subtypes.

MATERIAL AND METHODS

The prevalence of XMRV DNA in different histological subtypes of prostate adenocarcinoma was examined after characterizing the tumors into groups, using formalin-fixed, paraffin-embedded tissue samples from newly diagnosed prostate adenocarcinomas and archival prostate cancer tissue from our XMRV case control analysis. Broad-spectrum XMRV DNA amplification was performed by end-point polymerase chain reaction, using commercially available primer set.

RESULTS

The study included 100 patients with prostate cancer. XMRV DNA was detected in 4 of 8 (50%) ductal adenocarcinomas, exhibiting papillary and cribriform histological features. XMRV DNA was not detected in any other variant of adenocarcinoma including acinar (0/91) and mucinous carcinomas (0/1). Majority of XMRV positive cases were biologically aggressive and present cancer at an early age upon diagnosis.

CONCLUSION

Ductal adenocarcinomas demonstrate a significant association of XMRV DNA while other histological variants of prostate adenocarcinoma seem unrelated to XMRV infection.