Adenoid Cystic/Basal Cell Carcinoma of the Prostate: Review and Update

Basal Cell Carcinoma of the Prostate Misdiagnosed as High-Grade Urothelial Cancer - A Case Report of a Diagnostic Pitfall

Purpose

Basal cell carcinoma of the prostate is rare. Usually, it is diagnosed in elderly men with nocturia, urgency, lower urinary tract obstruction and normal PSA.

Case Presentation

We report on a case of a 56-years-old patient who presented at the emergency ward with weight loss, nausea and vomiting. The diagnostic evaluation showed acute renal failure due to a bladder tumor. After admission to the urology ward and subsequent contrast-enhanced CT urography and contrast-enhanced chest CT, a non-metastatic bladder tumor that infiltrated the right side of the bladder and seminal vesicles was found. High-grade muscle-invasive urothelial carcinoma was diagnosed from TURBT specimens, followed by radical cystoprostatectomy with pelvic lymphadenectomy and formation of ureterocutaneostomy sec. Bricker. The histopathological examination of the resection specimen surprisingly revealed the presence of prostatic basal cell carcinoma pT4N0M0 and not urothelial cancer. Due to renal failure, the patient required hemodialysis. The recommendation of the multidisciplinary oncological meeting was to follow up with the patient by the surgeon-urologist. On imaging six months after surgery, it was suspicious for recurrence. Patient was considered for adjuvant oncological treatment.

Conclusion

Although rare, basal cell carcinoma of the prostate should be considered in patients with lower urinary tract symptoms, hematuria and normal PSA. Transurethral resection of bladder tumor is indicated in patients presenting with hematuria and bladder tumor. In evaluation of such cases rare histological types should be included in the differential 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 This review combines an unpublished case report of a 55-year-old patient with BCC with an assessment of the latest literature.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.

Metastatic Prostatic Adenocarcinoma in Patient With Muir-Torre Syndrome Misdiagnosed as Metastatic Sebaceous Carcinoma: Case Report and Systematic Literature Review

Muir-Torre syndrome (MTS) is a rare autosomal dominant condition characterized by the presence of at least one cutaneous sebaceous tumor and one visceral malignancy, arising mostly from the gastrointestinal tract. We present the case of a 63-year-old man with several cutaneous and visceral neoplasias in the context of MTS, and a pelvic lymph node lesion diagnosed initially as metastatic sebaceous carcinoma, but later identified as metastasis from a newly diagnosed prostatic adenocarcinoma. Histological similarities between these 2 lesions are discussed. A systematic literature review was conducted evaluating all published cases of patients with MTS in which metastases were reported. Eighteen articles were included in the final synthesis, representing 20 patients with a total of 26 metastases. Seventeen patients (85%) exhibited metastases originating from MTS-related neoplasms, whereas only 2 patients (11%) exhibited metastases from concomitant malignancies. Of the 85% of patients with metastases from MTS-related malignancies, most originated from noncutaneous sources (78% from visceral neoplasms and 22% from sebaceous carcinomas). When stratifying according to metastases, 23 cases (88%) originated from MTS-related lesions, whereas only 3 (12%) originated from unrelated malignancies. Our findings thus demonstrate that most metastases found in MTS patients (88%) do indeed originate from MTS-related neoplasms. Nevertheless, it remains imperative that a broad differential diagnosis is maintained when assessing a novel lesion, to avoid misdiagnoses, as in the present case, with significant therapeutic and prognostic implications.

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.

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.

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.

MRI, enhanced CT, and FDG PET/CT in basal cell carcinoma of the prostate

Primary basal cell carcinoma of the prostate is a very rare neoplasm with a good prognosis. A 55-year-old man presented with urinary frequency for 2 months. Serum prostate-specific antigen level was normal. T2-weighted MR images showed an inhomogeneously hyperintense tumor in the prostate. Enhanced CT showed heterogeneous enhancement of the tumor. FDG PET/CT showed strong FDG uptake of the tumor with SUVmax of 14.1. Prostate biopsy findings revealed basal cell carcinoma with high proliferation index.

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.

Basal cell carcinoma of the prostate: a case report

A 69-year-old man presented with gross hematuria and irritative urinary symptoms. He underwent transurethral resection of his prostate. The prostate chips revealed 70% poorly differentiated carcinoma with neuroendocrine features, initially read as small cell carcinoma, later as basal cell carcinoma. PSA at this time was 0.3. He received 4 cycles of etoposide and cisplatin. After which, rebiopsy of the prostate showed tumor consistent with poorly differentiated basal cell carcinoma. Given progression on chemotherapy, decision was made to proceed with radical prostatectomy. Metastatic workup was negative. Gross extraprostatic invasion was noted but lymph nodes were free of metastatic disease.

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.

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.

Premalignant and malignant prostate lesions: pathologic review

BACKGROUND

High-grade prostatic intraepithelial neoplasia (HGPIN) is currently the only recognized premalignant lesion of prostatic carcinoma.

METHODS

This review article discusses HGPIN, its link to prostatic adenocarcinoma, and the significance of its presence on needle biopsy. The criteria and clinical impact of the diagnosis of atypical small acinar proliferation on needle biopsy are reviewed. Certain subtypes of prostate cancer that are not associated with HGPIN are of clinical relevance, and the unique clinicopathologic features of these subtypes are discussed. Histologic variants of prostatic adenocarcinoma with distinct cell types are also described.

RESULTS

HGPIN is the only known pathologic factor currently available to distinguish which patients may be at risk for detecting carcinoma on repeat biopsy. Histologic variants are recognized due to the inference of a particular Gleason grade pattern associated with the cell type, hence affecting prognosis. Typically, pure forms of these histologic variants are associated with worse prognosis due to the associated high Gleason grades.

CONCLUSIONS

HGPIN has a strong association with acinar-type prostatic adenocarcinoma. HGPIN and acinar-type prostatic adenocarcinoma both show similar molecular alterations, providing further evidence of their association.

A case of prostatic adenocarcinoma with aberrant p63 expression: presentation with detailed immunohistochemical study and FISH analysis

Prostate carcinomas showing aberrant diffuse-nuclear p63 expression are extremely rare, and there is only 1 article in the literature reporting a series of 21 such cases. We document an additional case of p63-positive prostatic adenocarcinoma in a 60-year-old man, whose diagnosis was difficult. The patient was found to have an elevated prostate-specific antigen (PSA) level at a general health check-up and was referred to the hospital. His serum PSA was 4.2 ng/mL. Digital rectal examination and transrectal ultrasonography did not reveal a lesion. Transrectal needle biopsy of the prostate detected atypical, small prostatic glands suspected for adenocarcinoma at 2 cores. However immunohistochemistry showed nuclear p63 expression in the suspicious glands. Repeat biopsy revealed only high-grade prostatic intraepithelial neoplasia. In the third transrectal biopsy, finding of the same atypical glands showing perineural invasion facilitated the diagnosis of malignancy. The patient underwent a radical prostatectomy. Five different small tumor foci were seen in the prostate after pathological evaluation, one of which was p63 positive and the others p63 negative. The largest of the classic p63-negative tumors showed a TMPRSS2-ERG translocation by fluorescent in situ hybridization while the p63-positive tumor did not. The authors submit that this subtype (p63-positive prostate adenocarcinoma) should be listed among the recognized rare variants of prostatic adenocarcinoma.

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.

Thymic basaloid carcinoma: a clinicopathologic study of 12 cases, with a general discussion of basaloid carcinoma and its relationship with adenoid cystic carcinoma

Thymic carcinoma (primary carcinoma of the thymic epithelium; type C thymoma) is a rare malignancy. It usually presents in middle-aged to elderly patients and can exhibit a wide variety of morphologic appearances. Thymic basaloid carcinoma (thymic BC) is a particularly rare subtype, with less than 20 cases published in the English literature, mostly in the form of individual case reports. In this study, we present the clinicopathologic and immunohistochemical features of 12 new cases of thymic BC. There were 10 (83%) men and 2 (17%) women. Ages at the time of initial diagnosis ranged from 34 to 77 years (mean 55 y). The 2 most common manners of presentation were dyspnea on exertion (3 patients) and as an incidental finding on radiographic imaging (2 patients). Tumors ranged in size from 4.4 to 17 cm (mean 10.1 cm). One of 12 cases (8.3%) was associated with a multilocular thymic cyst. Immunohistochemistry was performed in 8 cases. Pan-cytokeratin was positive in all cases. CD117 (c-kit) was positive in 6 of 8 cases (75%), p63 was positive in 7 of 8 cases (88%), p53 was positive in 7 of 8 cases (88%), ranging from <10% to 90%, CD5 was focally positive in 3 of 8 cases (38%), collagen type IV was positive in 4 of 8 cases (50%), and proliferative index, as estimated by Ki67, ranged from <1% to approximately 15%. In 1 of 2 cases with sarcomatoid differentiation, Ki67 was greater than 80% in the sarcomatoid area. Cases were negative for thyroid transcription factor-1 (0 of 8), S-100 (0 of 7), and synaptophysin (0 of 7). Long-term data was available in 8 patients with an average follow-up of 30 months. Five patients died of their disease at an average of 34 months from the time of diagnosis. Of the remaining 3 patients, 1 had a stable recurrence and died at 4 years from unrelated causes, and 2 were alive without the evidence of disease at 12 and 7 months, respectively. Thymic BC, although previously regarded as a low-grade neoplasm, has shown that it is capable of aggressive behavior and significant mortality. In this paper, we review the pertinent literature and discuss the possible relationship of thymic BC with thymic adenoid cystic carcinoma, as well as BCs and adenoid cystic carcinomas at other sites.

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.

The utility of transrectal real-time elastography in the diagnosis of prostate cancer

The aim of this study is to evaluate the diagnostic performance of transrectal real-time elastography (TRTE) to differentiate benign from malignant prostatic lesions, with pathologic diagnosis obtained by prostatic needle biopsy. Conventional gray scale transrectal ultrasonography (TRUS) and power Doppler ultrasonography (PDUS) were performed in 107 men who had elevated serum prostate-specific antigen level >4 ng/mL or abnormal findings on digital rectal examination. For baseline TRUS and PDUS imaging, the suspicion of carcinoma was scored using previously proposed five-point subjective scale. For TRTE imaging, we used newly adopted five-point subjective scale based on the degree and distribution of strain in relation to hypoechoic area, which simultaneously displayed on B-mode image. All patients underwent transperineal systematic 8-cores biopsies, as well as up to four cores of targeted biopsy from suspicious area by TRUS, PDUS and/or TRTE. The samples were diagnosed pathologically and compared with the findings of TRUS, PDUS and TRTE. Prostate cancer was detected in 40 (37%) of 107 patients. When a cutoff point of 3 (displaying focal asymmetric lesion without strain not related to hypoechoic lesion) was used, TRTE had 68% sensitivity, 81% specificity and 76% accuracy. TRTE was comparable with PDUS (70% sensitivity, 75% specificity and 73% accuracy) and had significantly higher sensitivity than TRUS (68% vs. 50%, p = 0.027). Combination of TRTE with PDUS increased sensitivity to 78%. The detection rate of directed biopsy from suspicious area in either TRTE or PDUS (TRTE+PDUS-directed biopsy) was 29% (31/107) by patient and was comparable with systematic biopsy (31%, 33/107, p = 0.86), whereas the detection rate of TRTE+PDUS-directed biopsy by core (55/111, 50%) was significantly higher than systematic biopsy (132/856, 15%, p < 0.0001). For assessing prostatic lesions, TRTE with B-mode image-based scoring had almost the same diagnostic performance as PDUS. Although TRTE+PDUS-directed biopsy detected comparable number of cancers with systematic biopsy, both techniques should be used supplementarily for minimizing the number of missing cancers.