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

Primary Adenocarcinoma of the Urinary Bladder: A Case Report on a Rare Malignancy

Of all primary bladder cancers, primary adenocarcinoma is an uncommon tumor. When considering all tumor origin areas, secondary bladder involvement from carcinoma, whether by direct extension or metastasis, is actually more prevalent than primary adenocarcinoma, despite its rarity. The most common source of subsequent bladder tumors is endometrial, lung, colon, prostate, breast, or other organ adenocarcinomas. Primary bladder adenocarcinoma is thought to result from urothelial metaplasia, which is frequently linked to persistent irritation or inflammation. Bladder exstrophy, recurrent urinary tract infections, long-term irritation from calculi or foreign bodies, and history of schistosomiasis are risk factors. A portion of these malignancies are associated with urachal remnants, where the tumor originates at the dome of bladder. Here we present a case of primary adenocarcinoma in a 44-year-old female patient that originated from the dome of urinary bladder.

Treatment of Villous Adenoma With Underlying Adenocarcinoma of the Prostatic Urethra Using Combined Chemoradiation: A Case Report

The presence of villous adenoma in the urinary tract is an exceedingly rare finding. On a histological and cytological level, this tissue is essentially identical to that typically found in the colon. These lesions do have malignancy potential and, when present with coexistent adenocarcinoma, have a risk of recurrence and metastasis even after surgical resection. Although villous adenomas of the urinary tract have been almost exclusively treated with surgical intervention in the literature, we present a case of villous adenoma with underlying adenocarcinoma of the prostatic urethra that was successfully treated with combined chemoradiation therapy. While surgical excision has been shown to be curative in diseases with isolated villous adenoma, more aggressive treatment with radiation and/or chemotherapy can be considered in patients with concurrent adenocarcinoma. However, more research into this subject is required to properly determine the best choice of therapy for this niche patient population.

Diagnostic Approach to and Differential Diagnosis of Clear Cell and Glandular Lesions of the Lower Urinary Tract

CONTEXT.—

A variety of glandular and clear cell lesions may be seen in the urinary bladder and/or urethra, ranging from benign to malignant primary and secondary tumors. Lesions with no malignant potential include reactive processes, such as nephrogenic metaplasia, and may show similar morphologic features as an infiltrative neoplasm, particularly in small biopsies. Similarly, ectopic tissues of Müllerian origin may be seen in the lower urinary tract, and their distinction from a true glandular neoplasm is essential to avoid overtreatment. A wide variety of primary and secondary malignant tumors exist with varying degrees of glandular and clear cell features. Therefore, surgical pathologists must be aware of the full scope of possible lesions to avoid misdiagnosis.

OBJECTIVE.—

To provide a practical framework for approaching the diagnosis of clear cell and glandular lesions of the urinary bladder/urethra and prostate, highlighting the strengths and limitations of various diagnostic features and ancillary tests.

DATA SOURCES.—

A review of the current literature was performed to obtain data regarding up-to-date diagnostic features and ancillary studies.

CONCLUSIONS.—

In summary, distinct morphologic and immunohistochemical features and clinical and radiologic correlation are essential to establish an accurate diagnosis when such cases with glandular and clear features are encountered in the lower urinary tract.

Mucinous adenocarcinoma derived from villous adenoma of the kidney with muconephrosis

Upper respiratory tract villous adenoma (VA) with muconephrosis is rare and should be included in the differential diagnosis when pelvic dilatation with a solid component is detected. VA may transform into malignant mucinous adenocarcinoma, which should be suspected if contrast enhancement on computed tomography (CT)/magnetic resonance imaging (MRI) and restricted diffusion on MRI are observed.

Precursors of urinary bladder cancer: molecular alterations and biomarkers

Clinical surveillance and follow-up of patients diagnosed with or at risk for urinary bladder cancers represent long-term, invasive, and costly processes for which supplemental biomarker information could help provide objective, personalized risk assessment. In particular, there are several precursors and possible precursors to urinary bladder cancer for which clinical behavior is heterogenous and interobserver variability in histopathologic diagnosis make it difficult to standardize management. This review seeks to highlight these precursor lesions from a diagnostic perspective (including flat urothelial lesions, papillary urothelial lesions, squamous lesions, and glandular lesions) and qualify known multiomic biomarkers that may help explain their behavior, predict patient risk, and acknowledge the nuance inherent to the question of whether these lesions are "benign" or "preneoplastic."

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.

Villous adenoma of the prostatic urethra

Primary villous adenoma originating from the urinary tract is an infrequent entity. We present a rare case of villous adenoma arising from a prostatic urethra with no sign of malignant transformation. Villous adenoma should be considered as one of the differential diagnoses of urethral lesions, especially if it has similar magnetic resonance imaging features as its colonic counterpart. Due to its potential for malignant transformation, its complete resection is mandatory.

Multifocal Urinary Tract Metastasis of Colorectal Carcinoma

INTRODUCTION

Secondary urinary tract tumors are uncommon findings and mainly evolve by direct invasion from adjacent organs. Actual metastatic involvement often develops in the urinary bladder, while the upper urinary tract is infrequently affected. In addition, the lungs, breast, and prostate gland are the usual primary sites. Colorectal carcinoma (CRC) may spread to the ureter directly or seeds via vascular or lymphatic channels. It may pose struggles in the differential diagnosis because CRC shares standard pathologic features with the primary adenocarcinoma of the urinary tract.

CASE PRESENTATION

We describe the case of an 81-year-old man who was referred to our hospital with a distal ureteral tumor that was treated by a ureteronephrectomy. The histopathological and genetic analysis established the diagnosis of metastatic CRC along with 3 metastases in the renal pelvis.

CONCLUSION

This rare case highlights the limitations of conventional histological processing, including immunohistochemistry, and it underlines the role of molecular investigations in certain circumstances.

Villous adenoma of bladder with uncommon location in a super-aged patient without gross hematuria

INTRODUCTION

There have been few reported cases of villous adenoma of the bladder. It commonly occurs in the superior area of the bladder with hematuria as the most common symptom. Here, we have presented a case of villous adenoma of the bladder neck and reviewed the existing literature.

CASE PRESENTATION

A 90-year-old man presented with voiding difficulty. Although urine analysis revealed microscopic hematuria and pyuria, the patient never complained about gross hematuria. Ultrasonography and cystoscopic examination revealed a bladder tumor located at the bladder neck. Transurethral resection was performed and villous adenoma was diagnosed by histopathologic examination.

CONCLUSION

Villous adenoma of the bladder is a rare disease, which is difficult to diagnose when the patient presents with uncommon clinical features. Although villous adenoma is known as a benign tumor, some reports suggest its association with malignancy. Therefore, careful management and follow-up are necessary.

Villous adenoma of the renal pelvis: a common entity at an uncommon location

Villous adenoma is uncommonly seen in the urogenital tract and is even more rarely seen in the upper urinary tract and renal pelvis. Like colorectal adenomas, these neoplasms can transform into adenocarcinoma. The preoperative diagnosis is challenging due to their frequent association with hydronephrosis. Herein, we present the case of a villous adenoma of the renal pelvis in a 62-year-old man presenting with recurrent urinary tract infection. The computed tomography scan showed marked hydronephrosis but no suspicious mass in the right kidney. A laparoscopic right nephrectomy was performed. Gross examination revealed a dilated renal pelvis with an irregular exophytic lesion in the renal pelvis’s upper surface. The histopathological examination showed slender, elongated villi with thin fibrovascular cores, consistent with villous adenoma morphology. Isolated villous adenomas have a favorable prognosis. However, the pathologist should undertake a search for an invasive component.

Villous adenoma of the urethra

Villous adenoma of the genitourinary system is rarely encountered by the general urologist. Although commonly seen in a colorectal practice, this tumor has been infrequently described in the urethra or bladder. In the genitourinary tract, this tumor appears to have excellent survival when isolated; however, it does have an association with adenocarcinoma of the genitourinary or gastrointestinal tract. Here we present a case of villous adenoma of the urethra managed with a multidisciplinary approach, which led to discovery of invasive adenocarcinoma of the rectum.

Villous Adenoma Arising in the Urethra of a Female with Bladder Augmentation History: A Case Report and Review of the Literature

Villous adenomas (VAs) in the female urethra are rare with only seven cases in the English literature to our knowledge. In patients with bladder augmentation cystoplasty, the neoplasia development risk increases and most of these develop in the neobladder or anastomosis line. Only two cases of VA developing from the native bladder mucosa have been reported. Physical examination of a 76-year-old female who had a history of augmentation cystoplasty revealed a caruncula-like structure protruding from the urethral meatus. The urinary USG showed that the lesion had no relation with the bladder. The lesion was excised. Microscopically, it consisted of villous structures covered with pseudostratified intestinal type epithelium. Low-grade dysplasia was present in the epithelium but high-grade dysplasia or in-situ/invasive carcinoma was not observed. Immunohistochemical study showed positivity for CK7, CK20, EMA, CEA and CDX2. The case was reported as VA of the urethra. We presented the first VA case arising in the urethra of a female patient with intestinal bladder augmentation. Excision is curative for pure VAs. Transformation to carcinoma or recurrence has not been reported. However, in one third of the cases, a malignant tumor may accompany the lesion. Therefore, all excision material should be examined carefully. Routine endoscopic follow-up should be performed in cases with bladder augmentation.

Villous adenoma of the urachus obscuring urachal adenocarcinoma: A case report

We report a case of a 78-year-old woman with a urachal tumor of the bladder wall. We performed a biopsy and revealed the tumor as a villous adenoma. We excised the tumor by partial cystectomy together with the umbilical ligament, because it was possible there was a co-existing malignancy. The tumor turned out to be villous adenoma and a urachal adenocarcinoma. Because the superficial section of the tumor consisted only of adenoma, a biopsy could not identify the malignant component. Villous adenoma of the urinary tract or the urachus is very rare, and it is considered as an intestinal premalignancy.

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We report a very rare case of villous adenoma mixed with urachal adenocarcinoma.

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The larger adenoma surrounded and obscured the adenocarcinoma.

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Superficial biopsy could not detect the more dangerous urachal adenocarcinoma.

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Detailed analysis of villous adenomas should be used to detect mixed malignancies.

Villous Morphology in Urinary Bladder Biopsy: An Approach to Diagnosis

Villous morphology in urinary bladder biopsy is a relatively uncommon finding. Villi are slender, finger-like structures that are commonly seen in the small intestine or in neoplastic lesions of gastrointestinal lineage/differentiation. Importantly, placenta also exhibits villi that are morphologically and functionally different from the intestinal one. Majority of the neoplastic lesions of urinary bladder are urothelial in origin with a minor subset showing glandular differentiation. While the presence of benign villi in urinary bladder biopsy necessitates a search for an occult perforation, provided a sample mismatch is ruled out, cytoarchitecturally abnormal/dysplastic villi indicate a neoplastic lesion of the urinary bladder encompassing villous adenoma and adenocarcinoma and urothelial carcinoma with villoglandular differentiation. The dysplastic villi in urinary bladder also imply a lower gastrointestinal endoscopy to rule out a colorectal primary. The development of the villous lesions in the urinary bladder and the colorectum are embryologically related and pose a major diagnostic challenge to the clinicians and surgical pathologists due to identical histomorphology and immunohistochemistry. We tend to discuss the morphological differentials and diagnostic approach to the villous lesions in the urinary bladder biopsy.

Glandular Tumors of the Urachus and Urinary Bladder: A Practical Overview of a Broad Differential Diagnosis

Primary glandular tumors of the urachus and urinary bladder are an intriguing group of clinically and morphologically diverse neoplasms for which there have been recent refinements in diagnostic subclassification and advances in molecular pathology. In addition, the urachus and urinary bladder may be secondarily involved by tumors with glandular differentiation that demonstrate remarkable morphologic, immunophenotypic, and molecular overlap. Thus, surgical pathologists need to be aware of the broad differential diagnosis of glandular tumors that involve the urachus and urinary bladder and have a practical diagnostic framework to evaluate these lesions in routine clinical practice. In this review, we summarize the salient clinical, morphologic, immunohistochemical, and molecular features of glandular tumors of the urachus and urinary bladder, including mucinous cystic tumors of the urachus, noncystic urachal adenocarcinomas, urothelial carcinomas with glandular or pseudoglandular features, primary urinary bladder adenocarcinomas, and Müllerian-type carcinomas, highlighting the strengths and limitations of various diagnostic features and ancillary tests, as well as the need for close clinical and radiographic correlation.

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.

Non-urothelial carcinomas of the bladder

Non-urothelial carcinomas involving the bladder are uncommon and often diagnostically challenging. These carcinomas may show squamous, adenocarcinomatous or neuroendocrine features, with immunohistochemical stains aiding the diagnosis in only a subset of cases. The clinical history in non-urothelial bladder carcinomas is important, given that the differential diagnosis often includes secondary involvement of the bladder by direct extension or metastasis from carcinomas at other sites. This paper will review non-urothelial carcinomas in each of these three morphological categories, emphasising recent changes in diagnostic grouping and challenges in the histopathological diagnosis. Review of bladder cancers with squamous morphology will include discussion of conventional squamous cell carcinoma and verrucous carcinoma and their distinction from urothelial carcinoma with extensive squamous differentiation. Bladder carcinomas with adenocarcinomatous change will include primary bladder adenocarcinoma, urachal adenocarcinoma and tumours of Müllerian type. Finally, neuroendocrine neoplasms of the bladder, including well-differentiated neuroendocrine tumour and neuroendocrine carcinomas, will be discussed. Associated surface findings, risk factors and prognostic features will be described.

Precursor lesions of the urinary bladder

The classification of neoplastic precursor lesions in the urinary tract has evolved slowly with the gradual accumulation of clinicopathological data. Current nomenclature was codified most recently by the 2016 WHO classification, which is based on primary data with clinical outcome, consensus group statements and considerations of practical utility in routine diagnosis. This review discusses precursor lesions of urothelial, squamous and glandular lineage. For urothelial neoplasia, both flat lesions with atypia and early 'difficult-to-classify' proliferations are considered. Subtypes of squamous metaplasia, florid non-invasive squamous proliferations and frank squamous dysplasia are also addressed. Finally, rare glandular precursors of adenocarcinoma are reviewed, to include intestinal metaplasia, glandular dysplasia and villous adenoma. For each category, morphology (including differential diagnostic considerations), immunohistochemistry and any known molecular correlates are detailed. The goal is to provide a concise, practical up-to-date overview of this complex topic.

Villous Adenoma Arising in the Native Bladder Mucosa and the Upper Urinary Tract With Coexisting Neuroendocrine Carcinoma Following Augmentation Cystoplasty

Villous adenomas arising in the bladder following augmentation cystoplasty procedures are exceedingly rare. Even rarer is their occurrence in the native bladder mucosa and the upper urinary tract. In this article, we present a unique case of multifocal recurrent villous adenoma involving native bladder mucosa of an augmented bladder, bilateral ureters, and renal pelvis, with coexistent foci of adenocarcinoma and neuroendocrine carcinoma, in a patient with history of augmentation colocystoplasty. We additionally discuss the pathogenesis of development of carcinoma in the setting of augmentation cystoplasty.

A Serrated Hyperplastic Colonic Polyp of the Urinary Bladder

Intestinal metaplasia of the urinary bladder can occur within the surface urothelium due to chronic irritation in repaired exstrophic urinary bladder. Colonic villous adenomas and tubulovillous adenomas with high-grade dysplasia and associated adenocarcinoma have been reported in adult patients with a history of augmented exstrophic bladder. To our knowledge, we report the first example of a nonadenomatous serrated hyperplastic colonic polyp in an elderly patient with a history of exstrophic bladder.

Biomarkers in Urachal Cancer and Adenocarcinomas in the Bladder: A Comprehensive Review Supplemented by Own Data

Urachal cancer (UrC) is a rare but aggressive cancer. Due to overlapping histomorphology, discrimination of urachal from primary bladder adenocarcinomas (PBAC) and adenocarcinomas secondarily involving the bladder (particularly colorectal adenocarcinomas, CRC) can be challenging. Therefore, we aimed to give an overview of helpful (immunohistochemical) biomarkers and clinicopathological factors in addition to survival analyses and included institutional data from 12 urachal adenocarcinomas. A PubMed search yielded 319 suitable studies since 1930 in the English literature with 1984 cases of UrC including 1834 adenocarcinomas (92%) and 150 nonadenocarcinomas (8%). UrC was more common in men (63%), showed a median age at diagnosis of 50.8 years and a median tumor size of 6.0 cm. No associations were noted for overall survival and progression-free survival (PFS) and clinicopathological factors beside a favorable PFS in male patients (p = 0.047). The immunohistochemical markers found to be potentially helpful in the differential diagnostic situation are AMACR and CK34βE12 (UrC versus CRC and PBAC), CK7, β-Catenin and CD15 (UrC and PBAC versus CRC), and CEA and GATA3 (UrC and CRC versus PBAC). Serum markers like CEA, CA19-9 and CA125 might additionally be useful in the follow-up and monitoring of UrC.

Urothelial tumors with villous morphology: Histomorphology and role of immunohistochemistry in diagnosis

Villous adenoma and urothelial carcinoma with villoglandular differentiation (UCVGD) are rare urothelial tumours showing villous morphology, the former being a preneoplastic entity and the latter being a malignant one. The detailed immunohistochemistry of these entities is previously not described in the literature. Moreover, a limited biopsy sample of UCVGD or a villous adenoma with or without adenocarcinoma may be difficult to distinguish on the basis of the histomorphology alone. An immunohistochemical panel comprising of GATA3, p63, β-catenin, CK7 and CK20 was performed on five cases of UCVGD and three cases of villous adenoma with the aim of studying the expression of the proteins thereby aiding in the diagnosis of these entities in a limited surgical pathology specimen. The mean age of UCVGD was 66.8 years and all the patients were male. All the cases of UCVGD were associated with high grade papillary urothelial carcinoma with lamina propria invasion. The immunohistochemical panel showed strong nuclear GATA3 expression in the urothelial component of UCVGD. Interestingly, the high grade and the low grade villoglandular components of UCVGD also expressed GATA3 (nuclear) with a progressive loss of expression from the high grade to the low grade component. The villous adenomas showed negativity or aberrant cytoplasmic positivity for GATA3. The β-catenin showed a gradual loss of membranous expression from villous adenoma to low grade and high grade villoglandular components of UCVGD with a patchy membranous expression in the urothelial component of the UCVGD. p63 showed strong nuclear positivity in the urothelial component and uniform negativity in the villous adenoma and villoglandular component of UCVGD irrespective of its grade, thereby distinguishing the villoglandular component from the urothelial component. The urothelial component of UCVGD showed strong membranous CK7 expression and was higher than the CK20 expression in the urothelial component. In contrast, CK20 expression was higher in villous adenoma as compared to CK7. There was no difference in the expression of CK7 and CK20 in the villoglandular components and low grade and high grade villoglandular areas. The above-mentioned immunohistochemical pattern may help to distinguish the UCVGD from the villous adenoma.

Pure Villous Adenoma of the Vesicoureteric Junction Presenting as Pyonephrosis

Villous adenomas of the urinary tract are uncommon neoplasms which share similar morphological features with gastrointestinal villous adenomas. Only two case series and around 20 scattered case reports of villous adenoma in the urinary tract have been published in English literature till date. They have been identified mainly in the urinary bladder, urethra, prostate and urachus, but the occurrence of villous adenomas at the vesicoureteric junction has not been described. We present a case of villous adenoma of the vesicoureteric junction which completely occluded the lumen and led to gross pyonephrosis.

Robotic approach to resection of villous adenoma of the urachus: a case report and literature review

Very few cases of villous adenomas of the bladder or urinary tract have been described. To our knowledge this is the first account of resection of an urachal villous adenoma via robotic laparoscopy, which is a safe and efficacious surgical approach. At this time, there is not enough evidence to suggest that progression of disease to carcinoma is the typical course. Nonetheless, follow-up cystoscopy is recommended after complete removal of the adenoma to monitor for recurrence. This case report reviews the current literature and describes a novel approach to treatment of this exceedingly rare entity.

Primary Villoglandular Mucinous Adenocarcinoma of the Vulva

Primary villoglandular mucinous adenocarcinoma of the vulva is rare tumor. We report a case of 68-year-old woman who developed this very uncommon malignant tumor. Immunohistochemical examination of this tumor revealed positive staining for Cytokeratin 20, Mucin 2, and CDX2, although Cytokeratin 7 and Mucin 6 were negative. This positive staining indicated the tumor enteric type characters. In order to exclude the possibility of the metastasis from another site, we thoroughly evaluated clinical data and extensively investigated the whole body. However, we could not detect any other tumors. The patient was treated by tumor resection. The patient remains free of disease 5 years after surgery.

Cytopathological features of villous adenoma of the urinary bladder in urine: A rare case report

Villous adenoma of the urinary bladder is a rare tumor that histologically mimics its enteric counterpart. Patients with an isolated villous adenoma have an excellent prognosis, but associated adenocarcinomas can frequently be identified in them as well. There is no literature that discusses the cytopathologic features of villous adenoma. Here we report a case which was diagnosed as villous adenoma histologically, which has been followed up with urine cytology. In urine cytology, many mucin producing cells are recognized. Few cell clusters show glandular formation or arrangement along the basement membrane. When glandular cells with columnar mucin-filled goblet cells are seen in urine cytology, the presence of a primary glandular lesion of the urinary bladder, such as villous adenoma, should be considered possible. Diagn. Cytopathol. 2016;44:632-635. © 2016 Wiley Periodicals, Inc.

Updates in the Pathologic Diagnosis and Classification of Epithelial Neoplasms of Urachal Origin

Since the publication of the World Health Organization "blue book" in 2004, several recent studies have provided new insights on the pathologic aspects of urachal neoplasms. The proposed updates include modified criteria for the diagnosis of urachal carcinoma. A uniform nomenclature for cystic tumors was lacking, and it is recommended that urachal mucinous cystic tumors should be separated and classified in a manner similar to ovarian mucinous neoplasms. The spectrum includes mucinous cystadenoma, mucinous cystic tumor of low malignant potential, mucinous cystic tumor of low malignant potential with intraepithelial carcinoma, and microscopically or frankly invasive mucinous cystadenocarcinoma, with 65% of cystic tumors classified as mucinous cystic tumor of low malignant potential. Most importantly, it has been shown that progression-free survival of noninvasive mucinous cystic tumors is significantly better than noncystic invasive adenocarcinoma. This development, along with prior descriptions of urachal villous adenoma, has also reaffirmed the occurrence of benign tumors of urachal epithelial origin. For noncystic (usual) invasive adenocarcinomas, the traditionally described histologic subtypes of enteric, mucinous, signet ring cell, not otherwise specified, and mixed remain appropriate, with 50% of tumors classified as mucinous subtype. Although this subtyping is helpful in diagnosis and differential diagnosis, the clinical significance of subtyping adenocarcinoma is still uncertain. Rare nonglandular morphologies such as urothelial, squamous, and neuroendocrine carcinoma in urachal carcinomas have been described in detail with proposals for their own set of diagnostic criteria. These criteria are based on unique features of urachal nonglandular carcinomas. Among the immunomarkers studied, only β-catenin and CK7 may be of help in the distinction of urachal from colorectal adenocarcinoma. Awareness of the expression profile of immunomarkers such as CDX2, P504S (racemase), PSMA, claudin-18, and REG IV in urachal tumors and in tumors in the differential diagnosis is important to avoid overreliance of these markers in the diagnosis. Limited studies have identified KRAS mutations interestingly only in mucinous adenocarcinoma and exclusive of MSI loss, and mutations in BRAF are not present. Several alternative tumor staging approaches (eg, Mayo, Ontario, TNM systems) different from the traditional staging proposed by Sheldon are used that provide better tumor distribution across stages; however, the prognostic utility of the stage substratification has yet to be validated in large prospective studies. Evidence though suggests that staging urachal cancer is most pertinent when dichotomized to tumors that have spread outside versus within the perivesical tissue. Only high tumor stage and residual tumor after surgery have been shown to be independent predictors of outcome. This review updates the contemporary classification of urachal epithelial tumors, which has informed the upcoming 2016 classification of World Health Organization tumors. We provide modified criteria for diagnosing urachal adenocarcinomas, which remains a clinico-pathologic exercise. The role of ancillary diagnostic methodology and issues pertaining to staging and prognostication are presented.

Villous Adenoma of the Urinary Bladder: A Brief Review of the Literature

Villous adenoma is a rare neoplasm in the urinary tract. It usually occurs in patients older than 50 years with a male predominance. The affected patients typically present with hematuria, irritative voiding symptoms, and mucosuria. The malignant potential of this entity has not been established, but some of the case series studies on bladder villous adenoma do suggest a possible association with malignant tumors. Findings on ultrasonography, computed tomographic scanning, magnetic resonance imaging, or on cystoscopic examination are nonspecific. Therefore, villous adenoma of the bladder is primarily a histologic diagnosis. This review will highlight the current theories on its pathogenesis and discuss its main histologic and immunohistochemical features to aid the diagnosis.

Preneoplasia in the prostate gland with emphasis on high grade prostatic intraepithelial neoplasia

There are a variety of morphological patterns and processes that have been implicated in the pathogenesis of prostate cancer. Prostatic intraepithelial neoplasia (PIN), inflammation with or without atrophy, and adenosis (atypical adenomatous hyperplasia) have all been given candidate status as precursor lesions of prostatic adenocarcinoma. Based on decades of research, high grade prostatic intraepithelial neoplasia (HPIN), a proliferative lesion of prostatic secretory cells, has emerged as the most likely morphological pre-invasive lesion involved in the evolution of many but not all prostatic adenocarcinomas. In this manuscript, we briefly discuss other proposed precursors of prostatic adenocarcinoma and then focus on the history, diagnostic criteria and morphology of HPIN. The incidence of HPIN and its relationship to prostate cancer is reviewed. The differential diagnosis of large glandular patterns in the prostate is discussed in depth. Finally, we summarise the recent clinicopathological studies evaluating the clinical significance of HPIN and discuss follow-up strategies in men diagnosed with HPIN.

[Urachal cancers]

Urachal cancer is a rare pathology (less than 1% among all bladder tumors) with a poor prognosis for all stages, because of clinical delay leading to a late diagnosis, difficult differential diagnosis with bladder cancer, and no consensus for the treatment, mostly about the chemotherapy for advanced stages, because there are no data from prospective studies. A surgical treatment can be performed for the localized stages, but there are no real guidelines for local relapses and metastatic progression treatment. Those cancers are not radio- or chemosensitive; nevertheless data from fundamental research are missing. As this pathology is really uncommon, there are no clinical studies with targeted therapies. The purpose of this review is to introduce the most important clinical and paraclinical features of those cancers, and the usual treatment performed.

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.

Complex mucinous cystadenoma of undetermined malignant potential of the urachus

Urachal mucinous neoplasms are rare and include both villous adenomas and invasive adenocarcinomas. These mucinous tumours should be completely excised as they can demonstrate aggressive clinical behaviour, including the development of pseudomyxoma peritonei. We describe a 70-year-old woman who presented with a lower abdominal mass and received a diagnosis of a rare, complex urachal mucinous cystadenoma of undetermined malignant potential. This tumour demonstrated extensive mucin extravasation into perivesical soft tissue, but was not associated with pseudomyxoma peritonei or any malignancy. Rarely described in the English literature, mucinous cystadenomas of the urachus should be treated similarly to their villous adenoma counterparts: with complete surgical excision to prevent local tumour recurrences.

Primary adenocarcinoma of the urinary bladder: differential diagnosis and clinical relevance

CONTEXT

Glandular lesions of the urinary bladder include a broad spectrum of entities ranging from completely benign glandular lesions to primary and secondary malignancies. Common benign bladder lesions that exhibit glandular differentiation include cystitis cystica, cystitis glandularis, von Brunn nests, nephrogenic adenoma, intestinal metaplasia, urachal remnant, endometriosis, and prostatic-type polyp. The World Health Organization defines primary adenocarcinoma of the bladder as an epithelial malignancy with pure glandular differentiation without evidence of typical urothelial carcinoma. Malignant lesions that should be included in the differential diagnosis of a primary adenocarcinoma of the bladder include noninvasive and invasive urothelial carcinoma with glandular differentiation and secondary malignancies involving the bladder by direct extension or metastasis. The recognition and distinction of these different entities may be a challenge for pathologists, but they are of great clinical importance.

OBJECTIVE

To review features of primary bladder adenocarcinoma as well as those entities that need to be differentiated from primary bladder adenocarcinoma, with emphasis on clinical findings, pathologic characteristics, and immunoprofiles.

DATA SOURCES

Selected original articles published in the PubMed service of the US National Library of Medicine.

CONCLUSIONS

The accurate diagnosis of adenocarcinoma of the urinary bladder is important and challenging. It has to prompt an extensive clinical workup to rule out other glandular lesions in the urinary bladder, especially the possibility of secondary involvement of the bladder by an adenocarcinoma from a different site.

Diagnostically challenging cases: what are atypia and dysplasia?

This article addresses the spectrum of atypia and dysplasia within the bladder epithelium and the diagnostic categories developed to further classify challenging lesions. In addition, the effects of inflammation, specific therapies, and instrumentation on the bladder mucosa as well as the associated difficulty in achieving the appropriate diagnosis are also discussed.

Intestinal type villous adenoma of the renal pelvis

Intestinal type villous adenomas are uncommon in the genitourinary tract. Most reported cases have been located in the urinary bladder or urachus. Villous adenoma arising in the renal pelvis or ureter is very rare. We present a case of an 81-year-old female who presented with difficulty voiding and mucosuria. A computed tomography scan identified right-sided hydronephrosis, renal parenchymal atrophy, nonobstructing calculi and a lower pole renal mass. She underwent open right nephrectomy. Histopathologic examination of the kidney revealed an intestinal type villous adenoma of the renal pelvis with high-grade dysplasia and focal areas suspicious for invasive adenocarcinoma. We review the four previously reported cases of intestinal type villous adenoma in the renal pelvis and discuss diagnosis and management of this unusual neoplasm.

Urachal mucinous tumor of uncertain malignant potential: a case report

Urachal mucinous tumor of uncertain malignant potential is very rare and is characterized by a multilocular cyst showing the proliferation of atypical mucin-secreting cells without stromal invasion. As in ovarian and appendiceal borderline tumors, it represents a transitional stage of mucinous carcinogenesis in the urachus. In addition, this tumor may recur locally and develop into pseudomyxoma peritonei. Due to its scarcity and diagnostic challenges, we report a mucinous tumor of uncertain malignant potential arising in the urachus.

Renal pelvic villous adenoma presented with mucusuria: report of a case and literature review

Villous adenomas of the urinary tract are an uncommon condition, and appear mostly in patients where the disease occurred in the lower urinary tract. In contrast, upper urinary tract villous adenomas are a rare condition. Currently, just three cases of villous adenoma in the renal pelvis have been published. Herein, we present the fourth case of a renal pelvic villous adenoma, along with muconephrosis and mucusuria. A 73-year-old man presented with abdominal discomfort and a palpable abdominal mass. He had a history of bilateral anatrophic nephrolithotomy, 8 years and 6 years earlier. The preoperative radiographic investigation showed severe right hydronephrosis. A right nephrectomy was carried out and the intraoperative finding showed severe perinephric adhesion and a great deal of mucus in the renal pelvis. The pathological examination showed a villous adenoma and urothelial metaplasia in the kidney.

Villous adenoma of the urinary bladder: rare location

Villous adenomas are common lesions of the gastrointestinal tract but they are rarely located in the urinary tract including the urinary bladder. There are a few case reports and series in the literature. Here we report a 43-year-old male patient who had a polypoid lesion located on the left lateral wall of the urinary bladder. Transurethral resection was performed. The diagnosis was ‘villous adenoma of urinary bladder’ with clinical and histopathological findings.

Villous adenomas are mostly seen in elderly males. The coexistence of villous adenoma with adenocarcinoma, squamous cell carcinoma, and urothelial carcinoma was observed but there is not clear evidence about progression to carcinoma, in spite of its colonic counterpart. Generally complete surgical resection is accepted as curative but there are no exact data about follow-up and recurrence. By presenting this case, we aim to emphasize that it is a rare but important lesion because of coexistence with malignancies and uncertain malignant potential.

Villous adenoma of the renal pelvis and ureter

Villous adenoma originating in the urinary tract is a rare condition. Mucus-filled kidney (muconephrosis), one of the manifestations of this condition, occurs due to intestinal type of metaplastic changes occurring in the urothelium. This condition is commonly associated with urolithiasis and/or chronic infection. Concomitant adenocarcinomatous changes in the urothelium may be present along with this and unless a careful search is made to identify this, this serious condition may be overlooked leading to an inappropriate follow-up and dire consequences. We are reporting the third case of muconephrosis due to villous adenomatous changes of the renal pelvis and ureter.

Urothelial carcinoma with villoglandular differentiation: a study of 14 cases

Tumors of the urinary bladder may have a variety of histological patterns. Tumors with either glandular or villous features, such as villous adenomas, in situ adenocarcinomas, invasive adenocarcinomas, and variants of urothelial carcinoma such as micropapillary carcinomas have been described. However, urothelial carcinomas with both villous and glandular features have not been well characterized. We identified 14 cases of urothelial carcinoma with villoglandular differentiation. These cases were defined as having villoglandular features if they contained superficial finger-like processes lined by epithelium having true glandular lumina. Mean patient age at presentation was 70 years (range: 46-84 years) with a male predominance (5:1). A total of 3 cases (21%) were non-invasive, five cases (36%) had lamina propria invasion, five cases (36%) had muscularis propria invasion and one case (7%) had extravesicular extension. A concurrent high-grade papillary urothelial carcinoma component was identified in 11 cases (79%), micropapillary component in 5 (36%) cases, in-situ urothelial carcinoma component in 3 cases (21%), plasmacytoid component in 3 cases (21%), invasive adenocarcinoma in 2 cases, sarcomatoid carcinoma component in one case (14%), and small-cell carcinoma component in 1 case (7%). Cystitis cystica et glandularis was present in 3 cases (21%). Angiolymphatic invasion was identified in 3 cases (21%). Histologically, the villoglandular components were composed of finger-like processes lined by glands intimately admixed with high-grade urothelial carcinoma. Many of the glands had cribriform features lined by non-mucin producing cuboidal to columnar cells. Urothelial carcinoma with villoglandular differentiation are high-grade tumors typically seen in elderly males, characterized by superficial filliform processes lined by glands intimately admixed with high-grade urothelial carcinoma (in situ or invasive) and other aggressive variants of urothelial carcinoma. These relatively rare tumors should be recognized as a variant of urothelial carcinoma.

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.