Adenoid Cystic/Basal Cell Carcinoma of the Prostate

Genomic Characterization of Prostatic Basal Cell Carcinoma

Basal cell carcinoma (BCC) of the prostate is a rare tumor. Compared with the more common acinar adenocarcinoma (AAC) of the prostate, BCCs show features of basal cell differentiation and are thought to be biologically distinct from AAC. The spectrum of molecular alterations of BCC has not been comprehensively described, and genomic studies are lacking. Herein, whole genome sequencing was performed on archival formalin-fixed, paraffin-embedded specimens of two cases with BCC. Prostatic BCCs were characterized by an overall low copy number and mutational burden. Recurrent copy number loss of chromosome 16 was observed. In addition, putative driver gene alterations in KIT, DENND3, PTPRU, MGA, and CYLD were identified. Mechanistically, depletion of the CYLD protein resulted in increased proliferation of prostatic basal cells in vitro. Collectively, these studies show that prostatic BCC displays distinct genomic alterations from AAC and highlight a potential role for loss of chromosome 16 in the pathogenesis of this rare tumor type.

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.

Histological patterns, subtypes and aspects of prostate cancer: different aspects, different outcomes

PURPOSE OF REVIEW

The most common prostatic cancers (PCa) are acinary adenocarcinomas. Histological subtypes have been variably defined. The purpose of this review is to discuss unusual histological patterns and subtypes of acinar adenocarcinoma, as well as other types of PCa and their prognostic and therapeutic relevance.

RECENT FINDINGS

The new term 'subtype' for morphologically defined tumor entities replaced the term 'variant' in the new 2022 classification of the WHO to allow for clear terminological distinction from genetic variants. The 2022 WHO classification mentions prostatic intraepithelial neoplasia (PIN)-like carcinoma, signet-cell-like adenocarcinoma, sarcomatoid carcinoma and pleomorphic-giant-cell adenocarcinoma of the prostate as true subtypes of acinary PCa. Other forms of acinary PCa are termed unusual histological patterns and include atrophic, foamy-cell, microcystic, pseudohyperplastic and mucinous patterns. Nonacinar forms of prostate cancer include other glandular PCa, the ductal adenocarcinoma and the treatment-associated neuroendocrine carcinoma, and nonglandular PCa, the adenosquamous carcinoma, the squamous cell carcinoma and the adenoid cystic (basal cell) carcinoma of the prostate.

SUMMARY

True subtypes of acinary PCa and other forms of glandular and nonglandular PCa show relevant differences in prognosis and treatment approach compared with classic acinary PCa. The relevance of unusual histological patterns mainly lies in their deceptive benign appearance and the need for pathologists to know about these entities for accurate and timely diagnosis.

Basal cell carcinoma of the prostate: a case report responding to the FGFR inhibitor pemigatinib and literature review

PURPOSE OF REVIEW

Due to the limited number of cases, there are no guidelines for basal cell carcinoma (BCC) of the prostate. This review combines an unpublished case report of a 55-year-old patient with BCC with an assessment of the latest literature.

RECENT FINDINGS

BCC of the prostate has previously been described in only approximately 140 cases. We describe the diagnostic process, including the uropathological and DNA-sequencing results, which allowed us to start an experimental treatment with pemigatinib. BCC of the prostate is associated with an aggressive biological and clinical behavior, such as recurrence and metastasis. Several immunohistochemical stainings are available to differentiate BCC from adenocarcinoma of the prostate. Based on pathology and results from next-generation sequencing (NGS), patients can be offered targeted therapies.

SUMMARY

With the aid of histological work-up and immunostaining, prostatic BCC can be accurately diagnosed. Our patient underwent radical prostatectomy and staged extended lymphadenectomy due to lymph node recurrence. The patient subsequently developed progressive disease and was treated with the FGFR-inhibitor pemigatinib. The patient's liver metastasis significantly responded. The present case confirms the possibility of aggressive behavior of prostatic BCC and highlights the importance of a thorough uropathological and molecular biological analysis with a precision medicine strategy.

Adenoid Cystic Carcinoma/Basal Cell Carcinoma of the Prostate: Overview and Update on Rare Prostate Cancer Subtypes

Adenoid cystic carcinoma/basaloid cell carcinoma of the prostate (ACC/BCC) is a very rare variant of prostate cancer with uncertain behavior. Few cases are reported in the literature. Data on treatment options are scarce. The aim of our work was to retrospectively review the published reports. Thirty-three case reports or case series were analyzed (106 patients in total). Pathological features, management, and follow-up information were evaluated. Despite the relatively low level of evidence given the unavoidable lack of prospective trials for such a rare prostate tumor, the following considerations were made: prostate ACC/BCC is an aggressive tumor often presenting with locally advanced disease and incidental diagnosis occurs during transurethral resection of the prostate for urinary obstructive symptoms. Prostate-specific antigen was not a reliable marker for diagnosis nor follow-up. Adequate staging with Computed Tomography (CT) scan and Magnetic Resonance Imaging (MRI) should be performed before treatment and during follow-up, while there is no evidence for the use of Positron Emission Tomography (PET). Radical surgery with negative margins and possibly adjuvant radiotherapy appear to be the treatments of choice. The response to androgen deprivation therapy was poor. Currently, there is no evidence of the use of truly effective systemic therapies.

Basal Cell Carcinoma of Prostate With MSMB-NCOA4 Fusion and a Probable Basal Cell Carcinoma In Situ: Case Report

Basal cell carcinomas of prostate (BCCP) are very rare. Most arise in the transition zone and thus are associated with lower urinary tract symptoms and rarely associated with elevated prostate-specific antigen (PSA). These features make diagnosis/early diagnosis difficult because of the routine protocols followed. Basal cell carcinomas have distinctive histopathological, immunohistochemical, and to some extent also different molecular characteristics. Basal cell carcinoma in situ (BCCIS) is a nonexistent histological lesion as per the current literature, but here is an attempt to describe it through this case.A 74-year-old man presented with hematuria and previous diagnosis of prostatic hyperplasia. Based on this history, he underwent a prostatectomy ad modum Freyer. Pathological examination surprisingly revealed a diffusely infiltrative tumor with nonacinar adenocarcinoma morphology and many glandular structures probably representing BCCIS. Tumor was diagnosed as BCCP. Patient presented with metastasis to the abdominal wall 8 months postprostatectomy.BCCP is an aggressive type of prostate cancer, which might be challenging to diagnose based on routine protocols. This results in delayed diagnosis and treatment and thus poor prognosis. Furthermore, patients with this subtype of prostate cancer need appropriately designed, and maybe a totally different follow-up regimen as PSA is of no use for BCCP patients. Finally, diagnosis of BCCIS, if agreed upon its existence needs to be studied in larger cohorts as a precursor lesion.

A Review Leveraging a Rare and Unusual Case of Basal Cell Carcinoma of the Prostate

Basal cell carcinoma (BCC) is a rare nonacinar variant of prostatic carcinoma. In spite of prostatic acinar adenocarcinoma being one of the most common carcinomas in prostate, <100 prostatic BCC cases have been reported to date. Adenoid cystic/cribriform histology has been described in varying proportions to occur in prostatic BCC and is reported to be associated with aggressive behavior and high risk of metastasis. Herein, we present a case of prostatic BCC with adenoid cystic morphology, comprehensively describe its immunohistochemical and MYB/MYBL1 gene rearrangement findings, discuss its differential diagnosis, and review the literature of this rare entity.

Benign mimics of prostate cancer

The histopathological diagnosis of prostatic adenocarcinoma is challenged by the existence of numerous benign mimics. Most of these lesions have no clinical significance and many do not need to be reported. Their clinical relevance lies in the risk that they are misinterpreted as cancer. This review presents the histopathological features of benign mimics and discusses their distinction from cancer. The lesions that are most often misdiagnosed as cancer are atrophy and its variants, including simple atrophy, partial atrophy and post-atrophic hyperplasia. Benign proliferations are a group of lesions with crowded small glands with no or little nuclear atypia. The most problematic entity of this group is adenosis, which may have a more alarming architecture than some cancers. A diagnostic problem with atrophy and several of the benign proliferations is that the glands often have a discontinuous or absent basal cell layer. Hyperplastic and metaplastic lesions include basal cell hyperplasia. Basal cell hyperplasia may especially mimic prostate cancer with its small dark glands, variable nuclear atypia and a pseudoinfiltrative pattern, which may be present. The anatomical structure that most often causes diagnostic problems is the seminal vesicle. The mucosa of the seminal vesicle contains small acini, often with very pronounced nuclear atypia that may be misinterpreted as cancer. Pathologists need to be familiar with these mimics, as a false positive diagnosis of prostate cancer may lead to unnecessary radical treatment.

Mutational and transcriptomic landscapes of a rare human prostate basal cell carcinoma

BACKGROUND

As a rare subtype of prostate carcinoma, basal cell carcinoma (BCC) has not been studied extensively and thus lacks systematic molecular characterization.

METHODS

Here, we applied single-cell genomic amplification and RNA-Seq to a specimen of human prostate BCC (CK34βE12⁺ /P63⁺ /PAP^- /PSA^- ). The mutational landscape was obtained via whole exome sequencing of the amplification mixture of 49 single cells, and the transcriptomes of 69 single cells were also obtained.

RESULTS

The five putative driver genes mutated in BCC are CASC5, NUTM1, PTPRC, KMT2C, and TBX3, and the top three nucleotide substitutions are C>T, T>C, and C>A, similar to common prostate cancer. The distribution of the variant allele frequency values indicated that these single cells are from the same tumor clone. The 69 single cells were clustered into tumor, stromal, and immune cells based on their global transcriptomic profiles. The tumor cells specifically express basal cell markers like KRT5, KRT14, and KRT23 and epithelial markers EPCAM, CDH1, and CD24. The transcription factor covariance network analysis showed that the BCC tumor cells have distinct regulatory networks. By comparison with current prostate cancer datasets, we found that some of the bulk samples exhibit basal cell signatures. Interestingly, at single-cell resolution the gene expression patterns of prostate BCC tumor cells show uniqueness compared with that of common prostate cancer-derived circulating tumor cells.

CONCLUSIONS

This study, for the first time, discloses the comprehensive mutational and transcriptomic landscapes of prostate BCC, which lays a foundation for the understanding of its tumorigenesis mechanism and provides new insights into prostate cancers in general.

Primary basal cell carcinoma of the prostate with concurrent adenocarcinoma

INTRODUCTION

Prostatic basal cell carcinoma is an extremely rare tumor, exhibiting various histopathological features and clinical spectrums of disease.

CASE PRESENTATION

A 69-year-old male presented to our department with 2 years of voiding difficulty and intermittent macroscopic hematuria. With a presumed diagnosis of benign prostatic hyperplasia, he underwent a transurethral resection of the prostate. Pathological examination revealed atypical basaloid cells forming solid nests. Robot-assisted radical prostatectomy was subsequently performed, confirming a diagnosis of basal cell carcinoma with coexisting acinar adenocarcinoma.

CONCLUSION

Although more cases of basal cell carcinoma are indolent than aggressive, there is no reliable method of differentiation between these presentations. Thus, we recommend radical surgery and 6-monthly disease surveillance until more is discovered about this very rare malignancy.

MYB-NFIB gene fusion in prostatic basal cell carcinoma: clinicopathologic correlates and comparison with basal cell adenoma and florid basal cell hyperplasia

Prostatic basal cell carcinoma is a malignant neoplasm composed of basaloid cells forming infiltrative nests and tubules, which may potentially be misdiagnosed as benign basal cell proliferations (i.e., florid basal cell hyperplasia or basal cell adenoma) and also closely resembles adenoid cystic carcinoma of the salivary gland. MYB-NFIB gene rearrangement occurs in 30-86% of salivary gland adenoid cystic carcinomas. We sought to further characterize MYB gene rearrangement in prostatic basal cell carcinoma and correlate MYB-NFIB fusion status with other clinicopathologic characteristics. To this end, FISH analysis for MYB-NFIB gene fusion using fusion probes was performed on formalin-fixed, paraffin-embedded tissue sections from prostatic basal cell carcinoma (n = 30), florid basal cell hyperplasia (n = 18), and basal cell adenoma (n = 4). Fourteen of 30 (47%) cases of basal cell carcinoma were positive for MYB-NFIB gene fusion FISH, and no cases of benign basal cell proliferations were positive (p < 0.05). FISH-positive patients (mean age = 63 years, range: 35-81) tended to be younger than FISH-negative patients (mean age = 70 years, range: 55-93). Most FISH-positive cases demonstrated adenoid cystic carcinoma-like morphology (57%), and most FISH-negative cases demonstrated nonadenoid cystic carcinoma-like morphology (93%); one case (FISH-positive) demonstrated areas with both adenoid cystic carcinoma-like and nonadenoid cystic carcinoma-like morphology. FISH-positive cases more frequently demonstrated perineural invasion (50% vs. 14%, p < 0.05) compared to FISH-negative cases. Conversely, tall basal cells (i.e., neoplastic cells at least two times taller than wide) were more frequent in FISH-negative cases than FISH-positive cases (93% vs. 36%, p < 0.05). Approximately, 50% of prostatic basal cell carcinoma harbor MYB-NFIB gene fusion. The majority of these cases were characterized by adenoid cystic carcinoma-like morphology, perineural invasion, and lack tall basal cells. Florid basal cell hyperplasia and basal cell adenoma are negative for MYB-NFIB gene fusion.

Primary Adenoid Cystic Carcinoma of the Liver: Case Report and Review of the Literature

Adenoid cystic carcinoma (ACC) is an uncommon tumor primarily occurring in the salivary glands and is relatively rare in other sites. In the liver, only one primary adenoid cystic carcinoma has been reported in the English literature. Here we presented a primary hepatic adenoid cystic carcinoma in a 44 years old male. We described its histopathologic features and its immunohistochemical profile, and reviewed the literature. The surgical treatment and patient follow up information was also presented.

Large-Gland Proliferations of the Prostate

Large-gland proliferations of the prostate have gained considerable attention in the past decade. The differential diagnosis is quite broad but can be refined using histologic criteria and, sometimes, immunostains. Pathologists have come to realize that cribriform and intraductal as well as ductal carcinomas are particularly aggressive patterns, and should name them in diagnostic reporting when present.

Basal cell carcinoma of the prostate: A case report and review of the literature

Basal cell carcinoma (BCC) of the prostate is a rare tumor exhibiting various morphological characteristics, and its progression varies from an indolent to an aggressive type, with local recurrence or distant metastasis. We herein report the case of a patient who was diagnosed with early-stage BCC of the prostate and treated by surgery. A 68 year-old-man visited our hospital for a follow-up for bladder cancer. In August 2017, his serum prostate-specific-antigen (PSA) level was measured to be 5.61 ng/ml and prostate biopsy was performed. Histological examination revealed BCC of the prostate, with immunostaining examination of tumor cells showing positive results for p63 but negative results for PSA. Imaging examination showed no metastasis. Retropubic radical prostatectomy with extended lymph node dissection was performed. Pathological examination of the surgical specimen revealed coexistence of a predominant basaloid component and an adenoid cystic-like tumor with cribriform appearance. There was no extracapsular infiltration or lymph node metastasis. The patient remained alive and recurrence-free after 1 year of follow-up.

Bimodality treatment of patients with pelvic adenoid cystic carcinoma with photon intensity-modulated radiotherapy plus carbon ion boost: a case series

Background

Treatment of patients with pelvic adenoid cystic carcinoma (ACC) remains a challenge owing to the rarity of the disease, the lack of data, and the relative radioresistance of these tumors.

Case reports

This case series presents the results of three patients with recurrent or inoperable pelvic ACC treated with intensity-modulated radiotherapy (IMRT) plus carbon ion (C12) boost. Patients received C12 therapy at a dose of 3 Gray equivalents (GyE) (relative biological effectiveness [RBE]) per fraction up to 24 GyE RBE, followed by 50 GyE of photon IMRT in 25 fractions.

Conclusion

IMRT plus C12 ion boost as a definitive or adjuvant treatment for pelvic ACCs seems to be a promising therapeutic option. No unexpected toxicity was detected and the observed toxicity remained consistently low. The initial treatment response is promising and similar to that experienced for head and neck ACCs.

Prostate Basal Cell Carcinoma: A Case Report

Prostate basal cell carcinoma (PBCC) accounts for 0.01% of all prostate cancers. A 68-year-old man complained of dysuria for 5 years on his initial visit. His PSA level was 3.87 ng/mL. Due to a diagnosis of benign prostate hyperplasia, he underwent transurethral resection of the prostate. A pathological examination revealed that basal cell-like atypical cells made alveolar with palisadal layout. Immunohistochemical analysis showed positive 34β12, P63, and Ki-67. Based on these findings, PBCC was diagnosed. Then, we performed radical prostatectomy. He was free from recurrence 22 months after the operation. We herein report an extremely rare case of PBCC.

Histopathology of Prostate Cancer

This review focuses on histopathological aspects of carcinoma of the prostate. A tissue diagnosis of adenocarcinoma is often essential for establishing a diagnosis of prostate cancer, and the foundation for a tissue diagnosis is currently light microscopic examination of hematoxylin and eosin (H&E)-stained tissue sections. Markers detected by immunohistochemistry on tissue sections can support a diagnosis of adenocarcinoma that is primary in the prostate gland or metastatic. Histological variants of carcinoma of the prostate are important for diagnostic recognition of cancer or as clinicopathologic entities that have prognostic and/or therapeutic significance. Histological grading of adenocarcinoma of the prostate, including use of the 2014 International Society of Urological Pathology (ISUP) modified Gleason grades and the new grade groups, is one of the most powerful prognostic indicators for clinically localized prostate cancer, and is one of the most critical factors in determination of management of these patients.

Clinical and molecular insights into adenoid cystic carcinoma: Neural crest-like stemness as a target

OBJECTIVES

This review surveys trialed therapies and molecular defects in adenoid cystic carcinoma (ACC), with an emphasis on neural crest-like stemness characteristics of newly discovered cancer stem cells (CSCs) and therapies that may target these CSCs.

DATA SOURCES

Articles available on Pubmed or OVID MEDLINE databases and unpublished data.

REVIEW METHODS

Systematic review of articles pertaining to ACC and neural crest-like stem cells.

RESULTS

Adenoid cystic carcinoma of the salivary gland is a slowly growing but relentless cancer that is prone to nerve invasion and metastases. A lack of understanding of molecular etiology and absence of targetable drivers has limited therapy for patients with ACC to surgery and radiation. Currently, no curative treatments are available for patients with metastatic disease, which highlights the need for effective new therapies. Research in this area has been inhibited by the lack of validated cell lines and a paucity of clinically useful markers. The ACC research environment has recently improved, thanks to the introduction of novel tools, technologies, approaches, and models. Improved understanding of ACC suggests that neural crest-like stemness is a major target in this rare tumor. New cell culture techniques and patient-derived xenografts provide tools for preclinical testing.

CONCLUSION

Preclinical research has not identified effective targets in ACC, as confirmed by the large number of failed clinical trials. New molecular data suggest that drivers of neural crest-like stemness may be required for maintenance of ACC; as such, CSCs are a target for therapy of ACC.

The pathology of unusual subtypes of prostate cancer

There are some current literatures describing the morphologic change of prostate carcinoma variants. Some subtypes do not respond to hormone deprivation therapy, for example adenosquamous and squamous cell carcinoma (SQCC), basaloid and adenoid cystic carcinoma (ACC), small cell carcinoma (SmCC), sarcomatoid carcinoma, urothelial carcinoma; some are defined in special Gleason grade, some develop different prognosis. So, it is very important to identify these rare subtypes to avoid misdiagnosis. In this review, we aim to describe the typical clinicopathological features of the rare variants of prostate cancer, including prostate acinar adenocarcinoma morphologic variants.

A subset of prostatic basal cell carcinomas harbor the MYB rearrangement of adenoid cystic carcinoma

Adenoid cystic carcinoma (ACC) is a basaloid tumor consisting of myoepithelial and ductal cells typically arranged in a cribriform pattern. Adenoid cystic carcinoma is generally regarded as a form of salivary gland carcinoma, but it can arise from sites unassociated with salivary tissue. A rare form of prostate carcinoma exhibits ACC-like features; it is no longer regarded as a true ACC but rather as prostatic basal cell carcinoma (PBCC) and within the spectrum of basaloid prostatic proliferations. True ACCs often harbor MYB translocations resulting in the MYB-NFIB fusion protein. MYB analysis could clarify the true nature of prostatic carcinomas that exhibit ACC features and thus help refine the classification of prostatic basaloid proliferations. Twelve PBCCs were identified from the pathology consultation files of Johns Hopkins Hospital. The histopathologic features were reviewed, and break-apart fluorescence in situ hybridization for MYB was performed. All 12 cases exhibited prominent basaloid histology. Four were purely solid, 7 exhibited a cribriform pattern reminiscent of salivary ACC, and 1 had a mixed pattern. The MYB rearrangement was detected in 2 (29%) of 7 ACC-like carcinomas but in none (0%) of the 5 PBCCs with a prominent solid pattern. True ACCs can arise in the prostate as is evidenced by the presence of the characteristic MYB rearrangement. When dealing with malignant basaloid proliferations in the prostate, recommendations to consolidate ACCs with other tumor types may need to be reassessed, particularly in light of the rapidly advancing field of biologic therapy where the identification of tumor-specific genetic alterations presents novel therapeutic targets.

Basal cell carcinoma of the prostate is an aggressive tumor with frequent loss of PTEN expression and overexpression of EGFR

Basal cell carcinoma (also referred to as adenoid cystic carcinoma) is a rare tumor of the prostate. Although largely characterized as indolent, poor outcomes have been reported in a considerable fraction of cases. As yet, optimum treatment strategies for this cancer have not been developed. This study investigates protein expression of common or potential molecular therapeutic targets and reports on the clinicopathological features of 9 new cases. We evaluated the expression of ERBB2, KIT, androgen receptor, PTEN, EGFR, ERG, and p53 via immunohistochemistry. We also examined EGFR amplification and TMPRSS2-ERG gene rearrangement by fluorescence in situ hybridization. The mean clinical follow-up was 44 months. We found that basal cell carcinoma behaved aggressively with almost one-half of the cases displaying high-risk pathologic features or local recurrence (44%). One patient died as a result of metastatic disease. The most consistent abnormalities included a loss of PTEN expression (56% of cases) and EGFR overexpression (67% of cases). EGFR overexpression occurred in the absence of gene amplification. The TMPRSS2-ERG rearrangement was not detected in any of the tumors studied, nor was ERG protein positivity identified by immunostaining. In addition, ERBB2, KIT, p53, and androgen receptor expressions were either absent or showed only weak, limited reactivity. Our results suggest that there is a high morbidity associated with this tumor, and more intense follow-up and additional treatment may be indicated. Furthermore, targeted therapies directed against the EGFR and PTEN proteins or their constitutive pathways may be promising for future clinical management.

Basal cell carcinoma of the prostate: clinicopathologic analysis of three cases and a review of the literature

Background

Although conventional adenocarcinoma accounts for the majority of prostatic carcinomas, it is important to recognize rare variants, like basal cell carcinoma (BCC), which has distinctive histopathological and biological features.

Case report

We analyzed three cases of prostatic BCC and all of them complained of acute urinary retention and digital rectal examination disclosed a stony hard prostate. However, all of them presented with low prostate-specific antigen. The diagnosis relied on transrectal ultrasound-guided needle biopsies or transurethral resection of the prostate (TURP). The microscopic findings suggested basaloid cells with large pleomorphic nuclei and scant cytoplasm, showing peripheral palisading and forming solid nests, and immunohistochemical markers like 34βE12, p63 and Ki67 staining, were positive. After active treatment, two of the patients are alive with tumor and one died five months after discharge from our hospital.

Basaloid carcinoma of the prostate: A literature review with case report

Basal cell carcinoma of the prostate (BCP) is a neoplasm composed of prostatic basal cells. There are only a few publications outlining the diagnosis, treatment, prognosis and outcome for BCP. Traditionally surgery has been used but these tumors also respond to concomitant chemo-radiotherapy. Using a BCP case report treated with radical chemo-radiotherapy from a chemotherapy regimen used in anal cancers, we propose an alternative management to the traditional options of radical surgery and radical radiotherapy.

[Importance of second opinions on histology of prostate biopsy specimens]

OBJECTIVE

The significance of a second opinion on the histological findings of prostate carcinomas as well as suspicious lesions on core needle biopsy specimens was studied in cases from the year 2008.

STUDY DESIGN

A total of 920 core needle biopsy specimens of the prostate were stained with H & E and when necessary immunohistochemical analyses were performed with basal cell markers p63, 34ßE12, PSA and AMACR (P504 S) and neuroendocrine markers such as synaptophysin and chromogranin. The modified Gleason grading system was used.

RESULTS

In 43.5% of suspicious lesions adenocarcinomas of the prostate were found. In 53.2% the findings of atypical small acinar proliferations or high-grade prostatic intraepithelial neoplasia (HGPIN) were confirmed with a recommendation of serum PSA and morphological controls. The suspicion of prostatic carcinoma could be confirmed in 87.2% by the diagnosis of adenocarcinoma. After Gleason grading 82.8% of all diagnosed carcinomas had scores 6 or 7(3 + 4) and belonged to the group of low grade carcinomas. High grade carcinomas were without diagnostic problems.

CONCLUSION

A second opinion on the histological analysis of suspicious lesions of the prostate as well as of confirmation of Gleason grading is a very important point of quality management of diagnostic steps of prostate carcinomas and may be helpful for different therapeutic strategies.

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.

Current perspectives on Gleason grading of prostate cancer

The 5-tier Gleason grading system for prostate cancer, introduced in 1966, has been proven to be one of the main independent predictors of prostate cancer outcome. This review addresses interobserver concordance in Gleason grading; the persistence of grading discrepancies with frequent upgrading from the biopsy to the prostatectomy specimen; the 2005 International Society of Urologic Pathologists' modifications to Gleason grading; the impact of this modified grading on grade migration and outcome prediction; and molecular correlates of cancer morphology. Data from the most recent years are emphasized.

Focal neuroendocrine differentiation in prostatic gland carcinoma with basaloid pattern

INTRODUCTION

Prostatic gland basal cell proliferations exhibit morphological continuum ranging from basal cell hyperplasia to basal cell carcinoma. In the following report, we described clinical features, morphological spectrum, neuroendocrine differentiation and histogenesis of prostatic gland basal cell carcinoma in our patient.

CASE REPORT

Hematoxylin-eosin (HE), Alcian blu-periodic acid schiff (AB-PAS) at pH 2.5 stained sections and the avidin-biotin-peroxidase complex (ABC), were performed on prostate gland paraffin-embedded tissue. Monoclonal antibodies directed against cytokeratin (34betaE12) which selectively stains basal cells, prostate specific antigen (PSA), chromogranine A, neuron-specific enolase (NSE), synaptophysin and CD56, were used. Basal cell proliferations exhibited a morphological continuum ranging from basal cell hyperplasia to prostatic gland carcinoma. In these prostatic lesions, positive reactivity was demonstrated for 34betaE12 and CD56. These findings indicate that the basaloid cells of basal cell hyperplasia, florid basal cell hyperplasia, atypical basal cell hyperplasia and basal cell carcinoma are derived from basal cells of the normal prostate gland suggesting a continuum in the progression of hyperplasia to benign and then malignant neoplasia. The presence of CD56 protein in the discovered lesions may be related to their neuroendocrine differentiation.

CONCLUSION

The fact, that our patient was well six years after the radical prostatectomy supports the belief of some authors that basal cell carcinoma represents a low grade carcinoma with an excellent prognosis.

Digital quantification of five high-grade prostate cancer patterns, including the cribriform pattern, and their association with adverse outcome

Proper grading of the cribriform prostate cancer pattern has not previously been supported by outcome-based evidence. Among 153 men who underwent radical prostatectomy, 76 with prostate-specific antigen (PSA) failure (≥0.2 ng/mL [0.2 μg/L]) were matched to 77 without failure. Frequencies of high-grade patterns included fused small acini, 83.7%; papillary, 52.3%; large cribriform, 37.9%; small (≤12 lumens) cribriform, 17.0%; and individual cells, 22.9%. A cribriform pattern was present in 61% (46/76) of failures but 16% (12/77) of nonfailures (P < .0001). Multivariate analysis showed the cribriform pattern had the highest odds ratio for PSA failure, 5.89 (95% confidence interval, 2.53-13.70; P < .0001). The presence of both large and small cribriform patterns was significantly linked to failure. The cumulative odds ratio of failure per added square millimeter of cribriform pattern was 1.173 (P = .008), higher than for any other pattern. All 8 men with a cribriform area sum of 25 mm(2) or more had failure (range, 33-930). Regrading cribriform cancer as Gleason 5 improved the grade association with failure, although half of all cases with individual cells also had a cribriform pattern, precluding a precise determination of the independent importance of the latter. The cribriform pattern has particularly adverse implications for outcome.

Role of p63 in cancer development

Since their initial identification p53 homologues p63 and p73 have been expected to play a role in cancer development due to their close homology to p53, notoriously one of the most mutated genes in cancer. However soon after their discovery the awareness that these genes were rarely mutated in cancer seemed to indicate that they did not play a role in its development. However a large number of data collected in the following years indicated that altered expression rather than mutation could be found in different neoplasia and play a role in its biology. In particular p63 due to its fundamental role in epithelial development seems to play a role in a number of tumors of epithelial origin. In this review we summarize some of the evidence linking p63 to carcinogenesis.

Adenoid cystic carcinoma of the prostate: case report on a rare entity and review of the literature

Adenoid cystic carcinoma is an unusual histological variant of prostatic carcinoma. Because of its rarity, the natural history of this tumor is not known. Here we report this rare entity in a 62-year-old man who presented with symptoms of urinary tract obstruction. Digital rectal examination and ultrasonography (USG) showed an enlarged hard nodular prostate. Serum prostate-specific antigen (PSA) and prostatic acid phosphate levels were found to be within the normal range. Transrectal ultrasound-guided 12 core biopsies of prostate showed morphological features of an adenoid cystic carcinoma in 8 cores (bilateral, mid and base) on histopathological examination. Immunohistochemistry performed for PSA on paraffin section was negative. After diagnosis, bilateral orchidectomy was performed, and hormonal therapy was started in the form of androgen receptor blocker. The patient was clinically stable during a limited follow up of six months.

A cribriform urothelial neoplasm of the renal pelvis: an adenoid cysticlike variant of inverted urothelial papilloma or florid ureteritis cystica?

Tumors with cribriform appearance, similar to that of salivary gland adenoid cystic carcinoma, have been described at various anatomic sites. We present an unusual polypoid tumor, discovered incidentally, in the renal pelvis of an elderly man. The mass displayed a prominent cribriform architecture, akin to adenoid cystic carcinoma with an immunophenotype that supported a urothelial origin. Because of its lack of significant invasive growth and other adverse morphologic features, this lesion will likely behave in a banal fashion. This cribriform urothelial neoplasm of the renal pelvis may, in fact, represent a variant of an inverted urothelial neoplasm with a prominent cystic component or florid ureteritis cystica. It is important for pathologists to recognize this growth pattern as a possible variant of urothelial tumors.

Basal cell carcinoma of the prostate: unusual subtype of prostatic carcinoma

Basal cell carcinoma of the prostate, which has been generally considered to be indolent, is an unusual histological type of prostatic carcinoma and is extremely rare. This tumor has been classified according to the prevalent pattern of growth as adenoid cystic carcinoma or basaloid cell carcinoma (BCC), with the former growth pattern being considered to be the main feature of this entity. A 67-year-old Japanese man was admitted to a general hospital with obstructive urinary symptoms. His prostate was slightly enlarged, stony hard, and with a rough surface on digital rectal examination, while serum prostate-specific antigen and prostatic acid phosphatase concentrations were within the normal ranges (0.007 and 0.9 ng/mL, respectively). 2-Fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (FDG-PET/CT) exhibited multiple accumulations suspicious for cancer metastases. Specimens obtained by prostatic needle biopsy showed immunohistochemical reactivity for cytokeratin 34βE12 and P63, findings that were identical to those seen in basal cell carcinoma. Basal cell carcinoma of the prostate is a rare tumor, reported in 56 cases so far, and among all these, the pure form of BCC is extremely rare. Immunohistochemistry is indispensable to distinguish this neoplasm from other unusual histological types of prostatic carcinomas. Our findings reveal that tumors with a basaloid cell-predominant pattern have significant potential for a poor prognosis, in contrast with the conventional understanding regarding this neoplasm.

Basal cell carcinoma of the prostate gland: a case report and brief review of the basal cell proliferations of the prostate gland

Basal cell proliferations within the prostate gland encompass a group of benign and malignant entities. Although basal cell hyperplasia is a common finding, basal cell carcinoma of the prostate gland is a rare tumor that can be mistaken by a benign condition and represents a diagnostic problem in genitourinary pathology. We report a case of basal cell carcinoma in a previously healthy 65-year-old man with urinary symptoms and low prostate-specific antigen. The microscopic findings are presented and the use of immunohistochemical markers classifying basal cell lesions of the prostate discussed.

Clinical relevance of the putative stem cell marker p63 in breast cancer

P63 is a member of the p53 family. This protein is crucial for the maintenance of a stem cell population in the human epithelium and necessary for the normal development of all epithelial tissues including mammary glands. In normal breast tissue, the p63 seems to be a specific myoepithelial cell marker. P63 expression has been described in highly aggressive ER negative basal-like breast tumors. The value of p63 expression in ER positive disease is less clear. The expression levels of p63 mRNA by Affymetrix microarray analysis in a combined cohort of 2,158 ER positive breast cancers and its prognostic and predictive impact were analyzed. Tumor samples containing large amounts of benign breast tissue, which will interfere with p63 measurement, were excluded prior to the analysis. Survival analysis revealed a better prognosis of ER positive breast cancer expressing p63 (n = 410; P < 0.036). No correlation of p63 with standard parameters was observed. In a subgroup analysis, endocrine-treated patients with high p63 expression showed a better prognosis than low p63 expression (P = 0.06; n = 186). In untreated patients, this effect was less clear (n = 148; P = 0.5). P63 is a positive prognostic factor in endocrine-treated ER positive breast cancer and might influence responsiveness to endocrine treatment. Thus, p63 could be helpful as a predictive factor for endocrine therapy.

Variants and Unusual Patterns of Prostate Cancer

Beyond the typical acinar morphology observed in most prostatic adenocarcinoma, a spectrum of morphologic variants and prostate cancer subtypes exists. These unusual entities may be further classified into (1) cancer morphologies arising by divergent differentiation of prostatic ductal, acinar, or basal cells and associated with unique clinical features 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 several variants, with emphasis on diagnostic criteria, differential diagnoses, and clinical significance.

Adenoid cystic/basal cell carcinoma of the prostate: case report

Although most prostate carcinomas belong to the conventional acinar type, unusual variants have been reported. The adenoid cystic/basal cell carcinoma of the prostate is a rare tumor with distinctive histopathologic features. There are quite few publications in the literature concerning the diagnosis, treatment, and prognosis of this neoplasm.

Methods.

A 71-year-old man had an increased PSA value (5.11 ng/dL); the prostatic biopsy examination was positive for adenoid cystic/basal cell carcinoma. For this reason we proceeded with radical prostatectomy. The histology examination showed an acinar conventional carcinoma and adenoid cystic/basal cell carcinoma. At eight months the patient did not show any recurrence.

Conclusions.

Various histologic and immunohistochemical features are helpful in recognizing the adenoid cystic/basal cell carcinoma of the prostate. Clinically, the only difference from a conventional adenocarcinoma is that the PSA value is usually normal or only slightly increased. This tumor has a biological potential that can result in metastases in some cases; the current treatment consists primarily in the surgical resection. A close, long-term follow-up is strongly recommended.