Basal cell carcinoma arising in 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.

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 the prostate diagnosed incidentally with holmium laser enucleation of the prostate: How can we detect prior to benign prostatic hyperplasia surgery?

INTRODUCTION

Basal cell carcinoma of the prostate is a rare prostate malignancy. Its diagnosis and treatment have not been well established yet.

CASE PRESENTATION

An 80-year-old man was referred to our hospital for undergoing holmium laser enucleation of the prostate with persistent lower urinary tract symptoms. Ultrasonography showed enlarged prostate (41.3 cc) with mid-lobe hypertrophy. His prostate-specific antigen and testosterone levels were 0.437 ng/mL and 873 ng/dL, respectively. Histological examination of the enucleated tissue confirmed basal cell carcinoma. The cells were positive for bcl-2, 34βE12, p63, and cytokeratin 5/6. Ki-67 labeling index was 5%. Subsequent staging computed tomography scan and bone scintigram showed neither lymph node nor distant metastasis. Currently, the patient is under close follow-up with imaging, endoscopy, and urodynamic study.

CONCLUSION

It is difficult for physicians to detect prostate basal cell carcinoma before benign prostatic hyperplasia surgery. In case of organ-confined disease, age and Ki-67 labeling index could be suggestive of subsequent treatment decision-making.

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.

An Unusual Case of Metastatic Basal Cell Carcinoma of the Prostate: A Case Report and Literature Review

Background: Primary basal cell carcinoma (BCC) is a rare prostate cancer. Currently, a standard treatment regime for BCC of the prostate is lacking and most patients have a poor prognosis. We reported on a patient with BCC of the prostate whose cancer metastasized after undergoing a radical prostatectomy and whose prognosis improved after treatment with etoposide.

Case Presentation: A 62-year-old male with a history of seminoma was admitted complaining of intermittent gross hematuria for 1 month. Following a prostate biopsy, the patient was diagnosed with BCC of the prostate and received radical prostatectomy and radiotherapy. Initially, the patient's symptoms improved; however, 2 years later, a chest computed tomography (CT) scan revealed lung nodules. The patient did not exhibit any symptoms of BCC of the prostate; however, pathological examination and immunohistochemical staining of the nodules confirmed metastatic BCC of the prostate. Chemotherapy with docetaxel and cisplatin was well-tolerated but did not slow disease progression. Next-generation sequencing revealed mutations in the ataxia telangiectasia-mutated (ATM), SWI/SNF-related matrix-associated actin-dependent regulator of chromatin subfamily b-member 1 (SMARCB1), and phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1) genes. The patient did not receive targeted therapy owing to financial limitations and instead, etoposide was administered. A 9-month follow-up chest CT scan showed an 80% reduction in existing lung nodules and no new nodules had developed.

Conclusion: Our patient, diagnosed with recurrent prostate BCC after receiving a radical prostatectomy, responded to treatment with etoposide. Radical prostatectomy and radiotherapy should remain first-line therapy; however, etoposide may be an alternative second-line therapy when other options are not available. Consensus regarding treatment plans, and the molecular mechanisms behind prostate BBC, must be elucidated.

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.

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.

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.

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.