Mucinous adenocarcinoma of urinary bladder type arising from the prostatic urethra. Distinction from mucinous adenocarcinoma of the prostate

Primary mucinous adenocarcinoma of the urethra: A contemporary clinicopathologic analysis of 17 patients

Mucinous adenocarcinoma of the urethra is rare. Here we performed a contemporary clinicopathologic analysis of this entity in both male and female patients. All cases with secondary tumors involving the urethra were excluded. Clinicopathologic parameters and follow up was obtained. Seventeen patients were included in the study, 9/17 (53 %) male and 8/17 (47 %) female. The mean patient age was 68 years (range: 53-88 years). The majority (11/17, 65 %) of patients were African American, with an even greater incidence (7/8, 87 %) in female patients. In male patients, prostatic urethra was the most common part of the urethra (6/9, 67 %) where the tumor arose from. Immunohistochemical stains were performed in 11/17 (65 %) tumors and were positive for CK20 (11/11, 100 %), CDX2 (11/12, 92 %), CK7 (8/9, 88 %), GATA3 (3/8, 37 %) and negative for NKX3.1, PSA, p63, PAX8, and Beta-Catenin. In resection specimens, tumors were categorized as pT2 (3/11, 27 %), pT3 (1/11, 9 %), and pT4 (7/11, 64 %). Lymph node status was categorized as pN0 (6/9, 67 %), pN1 (1/9, 11 %), and pN2 (2/9, 22 %). Available follow up data showed 7/13 (54 %) patients developed recurrence after surgical resection and chemotherapy, of which 3/7 (43 %) died of widespread metastatic disease. It is critical for pathologists and urologic oncologists to be aware of this entity in both male and female patients in view of potential diagnostic pitfalls, prognosis, and therapeutic implications.

Primary mucinous adenocarcinoma of the urethra: A clinicopathological analysis of 35 cases

AIM

Primary mucinous adenocarcinoma of the urethra represents an extremely rare entity. We sought to characterise further these tumours' clinicopathological, immunohistochemical and molecular features.

METHODS AND RESULTS

Thirty-five cases were identified, occurring in 18 males and 17 females. The mean age at diagnosis was 65 years (28-89 years). The main presentation symptoms were haematuria and urinary outlet obstruction. Microscopic analysis revealed that all 35 tumours have stromal dissection by mucin. Ten tumours showed villoglandular dysplasia, nine showed mucinous metaplasia, two showed adenocarcinoma in situ and four showed signet ring cell features. All tumours were immunopositive for CEA, while immunonegative for nuclear β-catenin; 19 of 23 (83%) expressed high molecular weight cytokeratin; 19 of 33 (58%) CK7; 28 of 34 (82%) CK20; 32 of 35 (91%) CDX2; 22 of 27 (81%) cadherin-17 (CDH-17); 26 of 29 (90%) SATB2; and one of 31 (3%) GATA3. Mismatch repair gene products, including MLH1, PMS2, MSH2 and MSH6, were immunopositive, suggesting the MSI-low genotype of mucinous adenocarcinoma of the urethra. BRAF V600E and ALK rearrangements were not detected. During the mean follow-up of 20 months, nine patients either developed distant metastasis or succumbed to the illness.

CONCLUSION

Our study, encompassing the most extensive series of 35 cases of primary mucinous adenocarcinoma of the urethra, provides crucial insights into its precise diagnosis, management and potential targeted treatments. We found a greater CDX2, SATB2 and CDH17 sensitivity in these urethral tumours for the first time, to our knowledge. We identified characteristics such as an MSI-low profile, non-V600E BRAF mutations and an absence of ALK rearrangements.

Mucin-producing urothelial-type adenocarcinoma of the prostate with sarcomatoid features and novel molecular phenotype

Introduction

Mucin-producing urothelial-type adenocarcinoma of the prostate is a rare tumor that may not elevate serum prostate-specific antigen, creating significant diagnostic and monitoring challenges. We evaluate our case in detail and review prior studies to demonstrate that the pathologic and molecular features of this tumor are distinct from conventional prostate adenocarcinoma.

Case presentation

Our patient had a remote history of radiation-treated conventional prostate adenocarcinoma and presented many years later with an abscess-like prostate mass leading to urinary obstruction and hematuria. Biopsy revealed mucin-producing urothelial-type adenocarcinoma of the prostate with concurrent sarcomatoid features. Molecular studies showed a unique phenotype involving alterations in the KRAS, PTEN, RAD21, and TP53 genes.

Conclusions

To our knowledge, this is the first report that describes sarcomatoid features and molecular mutations in mucin-producing urothelial-type adenocarcinoma of the prostate.

Mucinous adenocarcinoma of the prostatic urethra after brachytherapy for prostatic adenocarcinoma: a case series

Mucinous adenocarcinoma of the urethra is extremely rare, even more so in a setting of postradiation therapy, with only 3 cases reported up to date including the first case published by our group in 2011. In the present study, we included the long-term follow-up on our previously reported case and report 3 additional cases. This is the first case series to date of this rare disease entity. The aim of this study is to review the clinicopathologic features of mucinous adenocarcinoma of the prostatic urethra in patients after receiving brachytherapy for prostatic adenocarcinoma. We identified 4 patients with a mean age of 72 years, and a mean interval of 14.8 years from brachytherapy for prostate carcinoma (grade group 1). Patients presented with hematuria or urinary retention. A colonoscopy was performed in three-fourth of patients and was within normal limits. Three patients underwent cystoprostatectomy and 1 had a transurethral resection of the prostate. On gross examination, only tumor formed a 3.5 cm tan-gray, ulcerated, friable, and necrotic mass and 2 displayed either irregular red granular or thickened areas within the prostatic urethra. Abundant extracellular mucin pools dissecting the prostatic stroma were present in all tumors, with clusters of tumor cells floating in the mucin. The mucin pools were lined by pleomorphic pseudostratified columnar mucinous epithelium. Tumors were diffusely positive for CK20, CDX2 (4/4), and AMACR (2/2); they focally expressed CK7 (2/4), and lacked nuclear β-catenin expression (3/3). PSA, PSAP, NKX3.1, p63, and GATA3 were negative in the tumors tested. Among the 3 patients who underwent radical surgery, 2 had stage 2 tumors (confined to the prostatic urethra and prostate), and 1 had a stage 3 tumor, with seminal vesicle involvement. All 4 patients were alive without disease with a mean follow-up of 4.9 years. In conclusion, brachytherapy-associated mucinous adenocarcinoma of the prostatic urethra displays intestinal-type features as its non-radiation-related counterpart. It appears to lack a villous adenoma component, displays a different immunohistochemical profile with diffuse CK20 and CDX2 positivity, and is associated with lower stage and less aggressive behavior.

A Rare Case of Co-Existing Mucin-Producing Urothelial-Type Adenocarcinoma of the Prostate and Acinar Adenocarcinoma

Mucin-producing urothelial-type adenocarcinoma of the prostate is an extremely rare neoplasm, and its coexistence with acinar adenocarcinoma is exceptional. A 70-year-old man presented with treatment resistant symptoms of urinary obstruction. The serum prostate specific antigen (PSA) level was normal. Cystoscopy revealed a kind of "cottony fluff" in the prostatic urethra. A computed tomography (CT) scan and magnetic resonance imaging (MRI) showed a polylobulated, hyperintense lesion with mucinous content. It was located in the right lobe of the prostate and measured 35 × 27 × 35 mm. The bladder cavity did not show lesions and the gastrointestinal endoscopy was normal. Thus, the patient underwent a radical cystoprostatectomy. The histological sections showed the characteristics of a mucin-producing adenocarcinoma with extensive areas of mucin pools formation. No areas of necrosis, glandular urethritis, or carcinoma in situ were identified. Neither lymphovascular and perineural invasion nor lymph node metastases were identified. The immunohistochemical study showed diffuse positivity for keratin (KRT) 7, KRT20, and membranous beta-catenin and focal positivity for KRT34betaE12 and caudal-related homeobox gene 2 (CDX2). In addition, we identified a 10-mm focus of prostatic acinar adenocarcinoma that was positive for racemase and NKX3.1. There is no treatment algorithm for this condition; however, surgery (radical prostatectomy) with or without adjuvant chemotherapeutic treatment represents a therapeutic alternative.

Traditional Serrated Adenoma of the Urinary Bladder: The First Report

A 71-year-old woman was hospitalized with hematuria and underwent cystourethroscopy. Cystourethroscopy revealed a polypoid bladder tumor. Histopathologic examination showed complex villiform growth pattern, slit-like serrations, and ectopic crypts lined by epithelium with eosinophilic cytoplasm, pseudostratified elongated nuclei, consistent with traditional serrated adenoma. Nephrogenic and intestinal metaplasia with severe inflammation were present in adjacent bladder mucosa. Molecular study of the polyp revealed mutation (p.G12V) in codon 12 of exon 2 of the KRAS gene. Traditional serrated adenoma is a rare type of colonic serrated polyp, making up less than 1% of the colonic polyps with a predilection to distal colon. In the literature, there is no traditional serrated adenoma reported outside the gastrointestinal tract. Here in we report the first extra-gastrointestinal traditional serrated adenoma within the bladder and bladder diverticulum, arising from intestinal metaplasia. The present study reports an additional information on molecular background of this unusual bladder polyp.

Case Report: Prostate Adenocarcinoma With Mucinous Features of Normal-Level Serum PSA, Atypical Imaging, Biopsy-Negative, and Peculiar Urethrocystoscopic Manifestation

Background

Mucinous tumors of the prostate are seen as rare morphological variants of prostate carcinoma. Misdiagnosis and missed diagnosis are frequent clinically, especially when the clinical performance appears atypical. Furthermore, there has not been reported about the urethrocystoscopic performance of mucinous adenocarcinoma growing into the prostatic urethra so far.

Case Presentation

The current case report describes a 48-year old Asian male who was hospitalized because of intermittent gross hematuria for more than two months. The patient was diagnosed as prostatic space occupying lesions and an examination of needle biopsy was conducted on him, which did not indicate a definite malignancy. Transurethral plasma kinetic resection of the prostate (TUPKP) was performed for the patient, but the postoperative pathology revealed prostatic adenocarcinoma with mucinous features. Specifically, two cord-like neoplasms, extending to the bladder neck, were found through urethrocystoscopy in the prostatic urethra, both of which grew pedicles. The pedicles were situated on the right side of the parenchyma of the prostate. Finally, the patient underwent radical prostatectomy three weeks later.

Conclusion

Here, we reported a case that prostatic adenocarcinoma with mucinous features was diagnosed after TUPKP. The patient had normal serum prostate-specific antigen levels with atypical images and negative biopsy result. This report lays stress on the vigilance of clinicians in prostate mucinous adenocarcinoma and makes a description of its peculiar urethrocystoscopic manifestation, typical imaging, and unique growth pattern for the first time.

Urethral Mucinous Adenocarcinoma of the Prostate: An Uncommon and Diagnostically Complex Disease

A 66-year-old male presented with hematuria and mucosuria. A transurethral resection of the prostate revealed adenocarcinoma in situ with mucinous features. He underwent a robotic-assisted radical prostatectomy with lymph node dissection. Pathology confirmed T2 primary mucin-producing urothelial type adenocarcinoma in the prostatic urethra. Urothelial adenocarcinoma arising in the prostatic urethra is an uncommon disease that warrants clear differentiation from other malignancies due to its aggressive nature. The differential includes urologic and gastrointestinal malignancies making diagnosis complex. Accurate diagnosis is critical to providing appropriate treatment as these patients are at high risk of developing recurrence and metastatic disease.

Mucinous adenocarcinoma of the prostatic urethra following a remote history of primary brachytherapy for prostate cancer

Secondary malignancies are a known, albeit uncommon, complication of radiation for prostate cancer, either in the form of external beam radiotherapy or seed-implant brachytherapy. Of these secondary malignancies, mucinous adenocarcinoma of the prostatic urothelium is an extremely rare clinical entity that has only once been reported in the literature. We report the case of an 80-year-old gentleman who initially underwent low-dose brachytherapy for low-risk prostate cancer 18 years ago. He subsequently developed recurrent gross hematuria and obstructive voiding symptoms. He underwent cystoscopy and transurethral resection of a large tumor from within the prostate. Final pathology of the tumor revealed a mucinous adenocarcinoma. Further immunostaining revealed this is likely to have originated from the prostatic urothelium. Given his age, comorbidities, and no clear data demonstrating that aggressive extirpative surgery provides a clinical benefit, we elected to undergo surveillance. Clinicians should be aware of mucinous adenocarcinoma of the prostatic urethra as an extremely rare, radiation-induced malignancy. Once a diagnosis is made, extirpative surgery is an option for localized disease, although prognosis remains poor.

Villous adenoma coexistent with focal well-differentiated adenocarcinoma of female urethral orifice: A case report and review of literature

BACKGROUND

Villous adenomas of the urinary tract are uncommon. They are morphologically similar to and difficult to differentiate from their counterpart in the colon. The histogenesis and malignant potential are uncertain.

CASE SUMMARY

A 63-year-old woman was admitted to our hospital with a mass in the urethral orifice. Gross and microscopic pathological examination was suggestive of urethral villous adenoma with focal well-differentiated adenocarcinoma. The whole urethra and part of the bladder were excised. No further treatment was offered. Carcinoembryonic antigen, cytokeratin 7, cytokeratin 20, epithelial membrane antigen, and p53 protein were positive, and the ratio of Ki-67 was 60%. After follow-up at 11 mo, the patient was cured and had no recurrence.

CONCLUSION

Immunohistochemistry is important for differential diagnosis of villous adenoma of the urinary system. Complete surgical resection of the urinary tract is curative.

Aggressive course in a patient with mucin-producing urothelial-type adenocarcinoma of the prostate: A case report and review of the literature

Prostate cancer is one of the frequently seen types of cancers in men. The most frequent histological type of prostate cancer is the acinar adenocarcinoma. Mucin-producing urothelial-type adenocarcinoma of the prostate is a very rare subtype. The mucin-producing urothelial-type adenocarcinoma of the prostate has microscopic similarities with colon and bladder adenocarcinoma. It has a more aggressive clinical course and does not respond to androgen deprivation therapy. A 77-year-old male patient diagnosed with mucinous prostate cancer was presented in the current case report.

Co-existence of mucin-producing urothelial-type adenocarcinoma of the prostate and inverted papilloma of the bladder

Adenocarcinoma of prostate with mucinous differentiation arising in the male urethra is extremely rare, with only 21 cases reported in the previous literature. A diagnosis of mucin-producing urothelial carcinoma of the prostate is based on the pathology, immunohistochemistry, and clinical examination by excluding the secondary adenocarcinoma of the prostate. We present a case of unexpected mucinous urothelial carcinoma of prostate with co-existing inverted papilloma of bladder in a 57-year-old man. The patient underwent transurethral resection of the prostate (TURP) and transurethral resection of a bladder tumour (TUR-Bt), and the pathologic result showed mucinous prostate carcinoma and bladder inverted papilloma. Immunohistological stain was negative for prostate-specific antigen (PSA), prostate-specific acid phosphatase (PSAP), and P63, but positive for cytokeratin 7 (CK 7), CK 20, clone 34βE12 and P504S. A complete endoscopic examination was performed to exclude the secondary adenocarcinoma of prostate. This case illustrates the clinical and pathological features of a rare and unexpected mucin-producing urothelial carcinoma of prostate in a bladder neoplasm patient.

Primary mucin-producing urothelial-type adenocarcinoma of the prostatic urethra diagnosed on TURP: a case report and review of literature

BACKGROUND

Mucin-producing urothelial-type adenocarcinoma of the prostatic urethra is extremely rare. These lesions must be differentiated from other mucinous tumors including mucin-producing prostatic adenocarcinoma and metastases from either colonic or bladder primaries.

CASE PRESENTATION

We report here a case of urothelial-type adenocarcinoma arising from the prostatic urethra. The patient is an 81 year-old man with a history of pT1 urothelial cell carcinoma of the bladder status post trans-urethral resection of bladder tumor (TURBT) who initially presented with irritative lower urinary tract symptoms and mucosuria refractory to Flomax and finasteride. A shared decision was made for the patient to undergo trans-urethral resection of prostate (TURP). At the time of surgery, a papillary tumor emanating from the prostatic urethra was found and no urothelial lesions were noted in the bladder. Pathology of the resected prostatic chips revealed an invasive adenocarcinoma with intestinal-type differentiation that stained positive for CK7, CK20, and villin, but negative for PSA, PSAP, uroplakin, and CDX-2. Colonoscopy was normal and CT scan did not show any evidence of colonic lesions nor visceral or lymph node metastases. Thus, the patient was diagnosed with a primary urothelial-type adenocarcinoma of the prostatic urethra.

CONCLUSION

Herein we review the literature regarding this unusual entity, and discuss the differential diagnosis, immunohistochemistry, and the importance of correctly identifying this rare tumor.

Concurrence of villous adenoma and non-muscle invasive bladder cancer arising in the bladder: a case report and review of the literature

BACKGROUND

Villous adenoma arising in the urinary tract is rare tumor. Most cases have been identified as benign neoplasm in the colon. Villous adenoma of the gastrointestinal tract is thought arise from premalignant polyps. Here, we report a case of concurrence of villous adenoma and non-muscle invasive bladder cancer.

CASE PRESENTATION

An 85-year-old woman presented at our office because of gross hematuria. Cystoscopic examination detected two papillary tumors in the bladder. Each tumor was resected and diagnosed, respectively. Histopathology confirmed that the resected one tumor was a villous adenoma, and the other was urothelial carcinoma (T1, high grade). Immunostaining for cytokeratin (CK) 7, CK20 and Ki-67 confirmed that CK7: (-), CK20: (+) and Ki-67: (<=30%) in villous adenoma while CK7: (+), CK20: (+), and Ki-67: (70%) in urothelial carcinoma. Three months later from TUR, urothelial carcinoma recurred in the trigone. She received adjuvant intravesical immunotherapy with BCG post TUR for the recurrence site.

CONCLUSION

There were no specific findings on ultrasonography, CT, MRI or cystoscopic examination morphologically. Therefore, pre-pathological villous adenoma of the bladder is extremely difficult to diagnose. There are some case reports of solitary villous adenoma in the bladder or with coexisting adeno carcinoma. However, to the best of our knowledge, this is only the second report of villous adenoma in the bladder of coexisting urothelial carcinoma that has been published in the literature. Premalignant villous adenoma of the bladder is extremely rare and difficult to diagnose without histologic examination. Any suspicious lesion of the bladder should be biopsied and/or resected to confirm histology.

Mucin-producing tumors and tumor-like lesions involving the prostate: a comprehensive review

Mucin-producing tumors of the prostate include both primary and secondary tumors with mucinous differentiation or features involving the prostate gland. These tumors are relatively rare and have variable prognostic and therapeutic implications. Primary mucinous (colloid) adenocarcinoma of the prostate is defined as prostatic adenocarcinoma with mucinous differentiation involving 25% or more of the entire tumor. Another primary tumor of the prostate that may have mucinous features is primary mucin-producing urothelial-type adenocarcinoma of the prostate (mucinous prostatic urethral adenocarcinoma). Primary mucin-producing urothelial-type adenocarcinoma of the prostate is a distinct entity that typically arises from the prostatic urethra possibly from urethritis glandularis or glandular metaplasia with malignant transformation, and it is analogous to adenocarcinoma with mucinous differentiation arising from the urinary bladder. Signet ring cell tumors of the prostate, though rare, may also have mucinous features. Secondary tumors with mucinous differentiation that may involve the prostate include adenocarcinomas of the urinary bladder and colorectum. Pathologists should also be aware of mucin-producing tumor-like lesions involving the prostate, including mucinous metaplasia, and benign Cowper glands that may mimic malignancy. Herein we present an updated and comprehensive review of the clinicopathologic, immunohistochemical, molecular, and prognostic features of mucinous tumors and tumor-like lesions involving the prostate gland, with emphasis on mucinous prostatic adenocarcinoma and its mimickers, including potential diagnostic pitfalls.

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.

Mucin-producing urothelial-type adenocarcinoma of the prostate as a mimicker of colonic adenocarcinoma: a case report and review of the literature

A 59-year-old man presented with persistent urinary obstructive symptoms, gross hematuria, and mucusuria. Subsequently, a prostate-specific antigen (PSA)-negative mucin-producing urothelial type adenocarcinoma of prostate was found. The serum PSA level was within the normal limit. Colonoscopy, positron emission tomography, and other tumor surveys showed this to be the only prostate lesion. Microscopically, there was an adenocarcinoma with copious mucin production, with the formation of mucin pools. The neoplastic glands were variously arranged in cribriform, glandular, and villous adenoma-like patterns. This is a very rare tumor, of which there are only 20 cases reported in the literature in the English language. It is critical to distinguish it from mucinous acinar adenocarcinoma of the prostate and from metastatic adenocarcinoma of either the bladder or colon. This is mainly because mucin-producing urothelial type adenocarcinoma of the prostate has a different clinical behavior, and hence, the treatment plan is different from that for conventional prostatic adenocarcinoma. Specifically, it has a more aggressive clinical course and is unresponsive to hormone therapy.

Recurrent villous adenoma with high-grade dysplasia arising in a urethral diverticulum

Villous adenomas of the urinary tract are an uncommon, well-recognized entity, described in different locations. However, the occurrence of this lesion in the female urethral diverticulum is very unusual. We present the first case of a recurrent villous adenoma with high-grade dysplasia unassociated with adenocarcinoma, arising from a urethral diverticulum. A 75-year-old African-American female presented with urethral prolapse complaining of mild voiding difficulty, stress incontinence, and mild spotting of blood. Histological examination revealed a papillary lesion with finger-like processes lined by pseudostratified columnar epithelium with abundant goblet cells. There were focal areas with stratification to the luminal surface and loss of nuclear polarity and atypical mitoses, interpreted as villous adenoma with high-grade dysplasia. The lesion recurred at one year without evidence of malignant transformation. We also present a brief literature review of urothelial villous adenomas.

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.

Villous adenoma of the urinary bladder

Villous adenomas arising in the urinary tract are an uncommon occurrence. They have been identified in the urachus, urethra, prostate, and throughout the bladder. Villous adenomas arising in the bladder are rare tumors that have been described as isolated cases and a few case series. We report a new case of a large villous adenoma arising in the bladder that was treated by transurethral resection.

Primary mucin-producing urothelial-type adenocarcinoma of prostate: report of 15 cases

Prostatic urothelial-type adenocarcinoma arises through a process of glandular metaplasia of the prostatic urethral urothelium and subsequent in situ adenocarcinoma sometimes associated with villous adenoma. These prostatic adenocarcinomas are analogous to nonurachal adenocarcinomas arising in the bladder from cystitis glandularis. Only 2 cases of urothelial-type adenocarcinoma from an institution other than our own have been previously described. The distinction between adenocarcinoma from another organ secondarily involving the prostate, usual adenocarcinoma of the prostate, and prostatic urothelial-type adenocarcinoma can present a significant diagnostic challenge and has significant therapeutic implications. Fifteen cases of prostatic urothelial-type adenocarcinoma were retrieved from the consult files of one of the authors. Mean patient age at diagnosis was 72 years (range 58 to 93 y). All men had negative colonoscopies, clinically excluding a colonic primary. Bladder primaries were ruled out clinically or pathologically in radical resection specimens. Follow-up was available on all men with a mean of 50.3 months (range 2 to 161 mo). All men presented with urinary obstruction symptoms with 3 (20%) also having mucusuria and 2 (13.3%) also having hematuria. Four men (26.7%) developed metastatic disease and 8 (53.3%) died of disease. In 8/15 (53%) cases, glandular metaplasia of the prostatic urethra and contiguous transition to adenocarcinoma were identified. Multiple histologic patterns were observed including dissection of the stroma by mucin pools 15/15 (100%), villous features 7/15 (47%), necrosis 2/15 (13.3%), signet ring cells 3/15 (20%), perineural invasion 1/15 (6.7%), focal squamous differentiation 1/15 (6.7%), and a granulomatous inflammatory response 1/15 (6.7%). Immunohistochemical stains were negative for prostate specific antigen, prostate specific acid phosphatase, CDX2, and beta-catenin in all cases. Stains were positive for high molecular weight cytokeratin in 12/12 cases (100%), and CK7 and CK20 in 10/12 cases (83.3%). Prostatic urothelial-type adenocarcinoma is a rare aggressive cancer arising in the prostate. The differential diagnosis includes conventional prostatic mucinous adenocarcinoma and secondary infiltration from a colonic or bladder adenocarcinoma. Immunohistochemistry for prostate specific antigen, prostate specific acid phosphatase, and high molecular weight cytokeratin along with morphology can help rule out conventional prostate carcinoma. beta-catenin, CDX2, and clinical studies are needed to rule out colonic adenocarcinoma. As prostatic urothelial-type adenocarcinoma is entirely analogous to bladder adenocarcinoma in both, its morphology and immunophenotype, only clinical studies or in some cases pathologic examination of the cystoprostatectomy specimen can exclude infiltration from a primary bladder adenocarcinoma.

Urothelial-Type adenocarcinoma of the prostate mimicking metastatic colorectal adenocarcinoma

Adenocarcinoma arising in urinary bladder or prostatic urethra is uncommon. When they occur, the tumor can be mistaken for metastatic lesions, especially from the colon. Here we report the fifth case of a primary urothelial-type adenocarcinoma arising in the prostate which showed enteric differentiation. The patient was a 55 year-old male whose prostatic needle core biopsy showed a high grade adenocarcinoma which was initially thought to be metastatic colon cancer. A follow-up colonoscopy was unremarkable. Subsequent prostatectomy revealed a high grade adenocarcinoma which was positive for cytokeratins 7 and 20, carcinoembryonic antigen, CDX2, and high molecular weight cytokeratin, and negative for prostate specific antigen, prostate specific acid phosphatase and AMACR. A diagnosis of urothelial-type adenocarcinoma of the prostate was rendered. We review the literature regarding this entity, and discuss the differential diagnosis, emphasizing utility of immunohistochemistry in making the diagnosis. Finally, we speculate on the behavior of these rare tumors.

Mucinous adenocarcinoma of posterior urethra. Report of a case

Primary carcinoma of the male urethra accounts for less than 1% of malignancies in males. Mucinous adenocarcinoma of the urethra is extremely rare, and its biologic behavior is not well known. We report a case of mucinous adenocarcinoma showing the histologic features of colloid adenocarcinoma that appears to have evolved either by neoplastic degeneration of goblet cells found in the urethral epithelium or by malignant degeneration of persistent glandular elements of uretheritis cystica and glandularis.

Intestinal-type mucinous adenocarcinoma arising from the prostatic duct

We present a case of mucinous adenocarcinoma of intestinal type arising from the prostatic duct in a 72-year-old Japanese man. The patient presented with macroscopic hematuria. Cystourethroscopy exhibited a mucus deposit at the 5 o'clock position of the verumontanum portion. A transurethral biopsy specimen revealed mucinous adenocarcinoma. A radical retropubic prostatectomy was performed. In the prostatectomy specimen, the cancer lesion mainly showed intraductal growth in the prostatic ducts with scattered mucin lakes in the prostatic stroma. There were no abnormalities in the urethral epithelium. The cancer cells resembled the intestinal epithelium rather than either the prostatic duct or the acinar epithelium, which showed diffusely positive immunohistochemical staining for carcinoembryonic antigen, but showed negative staining for prostate-specific antigen. Therefore, these findings suggest mucinous adenocarcinoma of intestinal type arising from the prostatic duct. A number of cases with mucinous adenocarcinoma arising from the prostatic urethra resembling the present case have been reported, but this is the first known case of carcinoma arising from the prostatic duct.

Mucin-producing urothelial-type adenocarcinoma of prostate: report of two cases of a rare and diagnostically challenging entity

The differential diagnosis of mucin-producing adenocarcinoma of the prostate includes conventional prostatic adenocarcinoma with mucin production, secondary adenocarcinoma usually of colorectal origin and, very rarely, urothelial-type adenocarcinoma arising from either the prostatic urethra or proximal ducts. Conventional prostatic adenocarcinoma with mucin production is readily identified by routine microscopy and immunohistochemistry. The distinction between secondary adenocarcinoma and urothelial-type adenocarcinoma, however, can present a significant diagnostic challenge. In addition, documented examples of the latter in the prostate are exceptionally rare. A transurethral resection of prostate specimen and prostatic needle biopsies from two patients showing urothelial-type adenocarcinoma of the prostate were identified in our consultation files. One of the patients subsequently underwent a radical prostatectomy. Both patients had negative gastrointestinal endoscopic workups. Transurethral resection of prostate material from two patients with clinically confirmed secondary adenocarcinoma of colonic origin involving the prostate and a prostatectomy specimen with mucinous conventional prostatic adenocarcinoma were also identified for comparison purposes. Formalin-fixed, paraffin-embedded sections were stained for prostate-specific antigen (PSA), prostatic acid phosphatase, carcinoembryonic antigen, cytokeratin 7, cytokeratin 20 and high molecular weight cytokeratin 34betaE12. The urothelial-type adenocarcinoma cases were diffusely positive for cytokeratin 7 and focally positive for 34betaE12 and cytokeratin 20, consistent with an origin from the urothelium of the prostatic urethra or proximal prostatic ducts. In contrast, the secondary adenocarcinoma of colonic origin cases were diffusely cytokeratin 20 positive and either negative or focally positive for cytokeratin 7 and negative for 34betaE12. The mucinous conventional prostatic adenocarcinoma was positive for PSA and prostatic acid phosphatase and negative for cytokeratin 7, cytokeratin 20 and 34betaE12. All tumors were positive for carcinoembryonic antigen.

Immunohistochemistry in diagnostic surgical pathology of the prostate

Immunohistochemistry (IHC) can play an important role in diagnostic surgical pathology of the prostate. Basal cell markers, such as the 34betaE12 antibody and antibodies directed against cytokeratin 5 and 6 or p63, are very useful for demonstration of basal cells as their presence argues against a diagnosis of invasive prostatic carcinoma (PC). However, several benign mimickers of PC, including atrophy, atypical adenomatous hyperplasia (AAH), nephrogenic adenoma, and mesonephric hyperplasia, can stain negatively with these markers, and thus, a negative basal cell marker immunostain alone does not exclude a diagnosis of benignancy. Although there are examples in the literature of high grade PC that stain focally with some of the basal cell markers, these cases are usually readily diagnosed based on H&E appearances and are unlikely to be confused with these benign mimickers. Alpha-methylacyl-coenzyme-A racemase (AMACR) is a sensitive marker of PC (except for a few uncommon variants: atrophic, foamy gland, and pseudohyperplastic variants), and its detection by immunohistochemical staining in atypical prostatic lesions can be very useful in confirming an impression of adenocarcinoma. AMACR expression can also be identified in high grade prostatic intraepithelial neoplasia (PIN), prostatic atrophy, AAH, and benign prostatic glands, and accordingly, a diagnosis of PC should not be based solely on a positive AMACR immunostain, especially when the luminal staining is weak and/or noncircumferential. The use of AMACR/basal cell antibody cocktails has been found to greatly facilitate the distinction between PC and its benign mimickers, especially when only limited tissue is available for staining. Prostate specific antigen (PSA) and prostate specific acid phosphatase (PSAP) are both quite sensitive and fairly specific markers of PC (there are a few nonprostatic tumors that can express one or both), and are both very helpful in establishing or confirming the diagnosis of PC when the differential diagnosis includes other tumors that can involve the prostate such as urinary bladder urothelial carcinoma. 34betaE12, p63, thrombomodulin, and uroplakin III are additional urothelial associated markers useful in this differential diagnosis. CDX2 and villin are useful markers to diagnostically separate colonic adenocarcinoma from PC. AMACR positivity and negative basal cell marker reactions are useful to confirm the presence of residual PC after hormonal or radiation therapy. Pan-cytokeratin, PSA, and PSAP can also highlight subtle infiltrates of PC with hormonal or radiation therapy effect. PSA and PSAP immunohistochemical stains are valuable in confirming metastatic carcinoma as being of prostatic origin and should always be utilized in the diagnostic evaluation of metastatic adenocarcinoma of unknown primary origin in males.

Mucinous urothelial-type adenocarcinoma of the prostate

A case of mucinous urothelial-type adenocarcinoma of the prostate in a 68-year-old man is reported. This is a rare neoplasm which probably originates from the proximal prostatic ducts or the prostatic urethra. This tumor does not express prostate-specific antigen, in contrast to the more common mucinous adenocarcinoma of the prostate, and may be misdiagnosed as a secondary, mainly colorectal, tumor. Clinical examinations and immunohistochemistry may help in the differential diagnosis. Owing to local recurrences two transurethral resections of the prostate were performed in our patient during 3 years of follow-up. He died from this tumor 40 months after the first biopsy.

Expresión de cdx2 en lesiones de vejiga urinaria y uretra

BACKGROUND

CDX1 and CDX2 are transcription factors involved in the development and maintenance of the intestinal epithelial cell. Expression of CDX2 has been reported in normal and metaplastic intestinal epithelium, and in those adenocarcinomas with that cellular origin. We have analyzed the expression of this marker in reactive and tumoral lesions arising in urinary bladder, urethra and urachus.

METHOD

CDX2 was investigated through immunohistochemistry on paraffin-embedded tissue, using the labelled streptavidin-biotin method (LSAB2, Dako) with a monoclonal antibody (CDX2-88, BioGenex).

RESULTS

Expression of CDX2 was observed in intestinal-type cistitis glandularis, intestinal metaplasia of urinary bladder, bladder adenocarcinoma, mucinous urothelial-type carcinoma of prostatic urethra and urachal mucinous carcinoma. CDX2 was not detected in normal urothelium and prostatic glandular epithelium, Von Brunn nests, typical-type cistitis glandularis, glandular adenosis and transitional carcinoma.

CONCLUSIONS

Lesions, both benign and malignant, with enteric-cell morphological features show positivity for CDX2. Expression of this marker is not organ-specific but is just related to a cellular phenotype. Reactivity for CDX2 in an adenocarcinoma can be consistent with an origin in urinary tract or urachus.

Villous adenoma of the urinary tract: a lesion frequently associated with malignancy

Villous adenomas arising in the urinary tract are rare. We identified 18 cases of villous adenomas of the bladder, urachus, and prostatic urethra. Patients ranged in age from 53 to 93 years with an average age of 69.6 years and a male preponderance of 67%. In six cases (33%), the lesion was pure villous adenoma. In three cases (17%), there was villous adenoma with in situ adenocarcinoma. In six cases (33%) there was villous adenoma with in situ and infiltrating adenocarcinoma. One case (6%) had villous adenomas with in situ (noninvasive) papillary urothelial carcinoma. One case (6%) had villous adenomas with in situ adenocarcinoma and in situ papillary (noninvasive) and infiltrating urothelial carcinoma. The remaining case (6%) had villous adenoma with in situ and infiltrating adenocarcinoma and in situ (noninvasive) papillary and infiltrating urothelial carcinoma. Clinical outcome was available in eight of the cases, with a mean follow-up of 4.6 years. No evidence of recurrence was found in two patients with pure villous adenoma or in two patients with villous adenoma and only in situ adenocarcinoma, all of whom were treated by nonradical excision. However, two of three cases with infiltrating cancer developed distant metastases despite radical surgery; the remaining patient was disease-free 11 years after transurethral resection. The case with villous adenoma and in situ urothelial carcinoma progressed to sarcomatoid urothelial carcinoma following partial cystectomy. Eight of 10 villous adenomas cases studied expressed the epitope for mAbDas1, found on colonic epithelium and primary adenocarcinomas of the bladder and urachus but not on normal or neoplastic urothelium. This study expands the spectrum of histologic features accompanying villous adenomas of the urinary tract. Coexisting infiltrating adenocarcinoma is often present, necessitating thorough sampling of any lesion diagnosed by biopsy as villous adenoma. Pure villous adenoma and those well-sampled lesions also containing in situ adenocarcinoma portend a favorable prognosis, even without radical treatment. Coexisting in situ or infiltrating carcinoma suggests a more aggressive course. Histologically, immunohistochemically, and prognostically, these lesions appear analogous to their counterparts in the intestine.

[Mucinous carcinoma of the prostate: critical review of Elbadawi's criteria]

OBJECTIVES

We present our experience on prostatic mucinous adenocarcinoma and at once we practice an actualization and a critical review of Elbadawi's criteria.

METHODS

After reviewing 206 prostatic carcinomas diagnosed in our hospital, we describe one case that fulfill criteria for being considered a prostatic mucinous adenocarcinoma. We also carry out a wide literature review trying to define anew the including criteria of this tumour by the light of modern knowledge and technology.

CONCLUSIONS

We think that for accepting a tumour as a prostatic mucinous adenocarcinoma, this have to fulfill the following criteria: 1. "More than 25% of a significative tumoral sample is mucinous pattern and present, single or clustered, tumour cells floating in immunohistochemically probed, acidic and neutral, mucin lakes". 2. "Tumour is Gleason 3-4 cribiform pattern with direct transition to colloid areas and usually coexist with classic adenocarcinoma but papillary growth patterns should be excluded. Tumour may contain a moderate proportion of signet-ring cells". 3. "Immunohistochemical staining for PSA have to be strongly positive in both, cribiform and mucinous, areas". 4. "Those PSA nonreactive, or only focally positive, mucinous adenocarcinomas, could be labeled as prostatic only when local or distant mucinous carcinomas are ruled out".

Villous adenoma of the urinary tract: a report of 23 cases, including 8 with coexistent adenocarcinoma

Villous adenoma originating in the urinary tract is uncommon. We present the first study of a large number of cases of villous adenoma of the urinary tract with clinical follow-up. Our series consisted of 15 patients with isolated villous adenoma and 8 patients with coexistent adenocarcinoma. The tumors occurred in elderly patients and had a predilection for the urachus, dome, and trigone of the urinary bladder. The typical clinical presentation was hematuria and irritative symptoms, and endoscopic examination usually identified a tumor growth. There was no gender predominance. Light microscopic examination showed morphologic similarity to colonic villous adenoma in all cases. Each tumor was composed of pointed or blunt finger-like processes lined by pseudostratified columnar epithelium. The epithelial cells displayed nuclear stratification, nuclear crowding, nuclear hyperchromasia, and occasional prominent nucleoli and mitotic figures. There was intense carcinoembryonic antigen immunoreactivity on the luminal surfaces (89%). Most cases (78%) contained cytoplasmic acid mucin, demonstrated by Alcian blue periodic acid-Schiff stain. Cytokeratin 20 was positive in all cases, cytokeratin 7 was positive in 56% of cases, and epithelial membrane antigen was positive in 22% of cases. Recurrence or invasive adenocarcinoma did not develop in any patient with isolated villous adenoma during a mean follow-up of 9.9 years. Lung metastasis developed in one patient with coexistent adenocarcinoma and multiple recurrences in another (mean follow-up, 3 years). We conclude that the prognosis is excellent in patients with isolated villous adenoma, and complete surgical resection is curative. Patients with coexistent adenocarcinoma may experience recurrence or distant metastasis, and more aggressive treatment may be indicated.

FEMALE URETHRAL ADENOCARCINOMA: IMMUNOHISTOCHEMICAL EVIDENCE OF MORE THAN 1 TISSUE OF ORIGIN

PURPOSE

Urethral adenocarcinoma is a rare malignancy whose origin remains controversial. The monoclonal antibody mAbDas1 (formerly 7E12H12) was developed against a unique colonic epithelial epitope and is reactive in areas of intestinal metaplasia. Recently the antibody was shown to react in cystitis glandularis as well as adenocarcinoma of the bladder, suggesting that cystitis glandularis may be the precursor of bladder adenocarcinoma. We examined urethral adenocarcinomas and benign urethral specimens using mAbDas1 to determine whether it could provide insight into their histogenesis.

MATERIALS AND METHODS

Archival tissue from 12 cases of primary female urethral adenocarcinoma and urethral specimens of inflamed urethral mucosa, urethritis glandularis and transitional cell carcinoma was studied. Immunohistochemical analysis of formalin fixed, paraffin embedded archival tissue was done using the monoclonal antibody mAbDas1. Tumors were also evaluated with a prostate specific antigen (PSA) polyclonal antibody as previous studies have noted PSA reactivity in these tumors.

RESULTS

Of the 12 cases 9 were columnar/mucinous adenocarcinoma, 2 clear cell adenocarcinoma and 1 a cribriform pattern resembling adenocarcinoma of the prostate. All columnar/mucinous adenocarcinomas reacted positively (6 strongly and 3 focally) with the mAbDas1 antibody but did not react with the PSA antibody. The tumor with a cribriform pattern reacted strongly with PSA but did not react with mAbDas1. The 2 clear cell adenocarcinomas did not react with either antibody. The benign urethral specimens demonstrated strong reactivity to the mAbDas1 antibody in areas of urethritis glandularis but normal and inflamed urethral mucosa and transitional cell carcinoma did not react.

CONCLUSIONS

Primary adenocarcinoma of the female urethra arises from more than 1 tissue of origin. Columnar/mucinous adenocarcinomas of the female urethra and urethritis glandularis demonstrate consistent reactivity with the mAbDas1 antibody, suggesting that these tumors arise from glandular metaplasia analogous to the potential histogenesis previously demonstrated in the bladder. PSA reactivity occurred in 1 tumor with a cribriform pattern and likely represents origin from Skene's glands. Clear cell adenocarcinomas did not react with either antibody, suggesting a third possible pathway in the development of this rare subset of adenocarcinomas.