Urothelial carcinoma with abundant myxoid stroma

Identification of uromodulin deposition in the stroma of perinephric fibromyxoid nephrogenic adenoma by mass spectrometry

Nephrogenic adenoma (NA) is an epithelial lesion that usually occurs in the mucosa of the urinary tract. Rare cases of deep infiltrative or perinephric lesions have also been reported. Recently, NA with characteristic fibromyxoid stroma (fibromyxoid NA) has been proposed as a distinct variant. Although shedding of distal renal tubular cells due to urinary tract rupture has been postulated as the cause of NA in general, the mechanism underlying extraurinary presentation of NA and fibromyxoid stromal change in fibromyxoid NA remains unknown. In this study, we performed mass spectrometry (MS) analysis in a case of perinephric fibromyxoid NA of an 82-year-old man who underwent right nephroureterectomy for distal ureteral cancer. The patient had no prior history of urinary tract injury or radiation. Periodic acid-Schiff staining-positive eosinophilic structureless deposits in the stroma of fibromyxoid NA were microdissected and subjected to liquid chromatography/MS. The analysis revealed the presence of a substantial amount of uromodulin (Tamm-Horsfall protein). The presence of urinary content in the stroma of perinephric fibromyxoid NA suggests that urinary tract rupture and engraftment of renal tubular epithelial cells directly cause the lesion.

Invasive urothelial carcinoma with chordoid features or abundant myxoid stroma: A reappraisal of morphologic spectrum and risk stratification based on molecular classification

Urothelial carcinoma (UC) with myxoid stroma or chordoid features is a rare diagnosis. We retrospectively collected data from 17 cases of diagnosed UC with myxoid stroma, mucin production, or chordoid features. We aimed to investigate the molecular subtypes of this neoplasm and to assess subtype correlations with clinical outcomes. Immunohistochemical (IHC) staining with a panel composed of markers for basal subtypes (CK5/6, CK14, and CD44) and luminal subtypes (GATA3, FOXA1, and CK20) was performed. Morphologically, all cases included an at least partial conventional UC component, with the first histologic pattern, named as "typical", characterized by a small- or medium-sized tumor cell nest. The second histologic pattern, named as "chordoid", was characterized by tumor cells with cording that mimic extra-skeletal myxoid chondrosarcoma or chordoma, and the third histologic pattern, named as "sarcomatoid", was characterized by non-cohesive spindle tumor cells with a mucin-producing or myxoid stroma background. The "typical" cases showed [CK5/6- CK14- CD44-] [GATA3 + FOXA1 + CK20-] IHC results and was classified as lumina subtype. The "chordoid" cases showed [CK5/6 + CK14 + CD44-] [GATA3- FOXA1- CK20-] IHC results and was classified as basal subtype, and the "sarcomatoid" cases showed [CK5/6- CK14- CD44+] [GATA3- FOXA1- CK20-] IHC results and was "not classified". All pT3 cases and all cases with lymph node (LN) metastasis belonged to the "sarcomatoid" pattern. All patients who had metastasis or died showed the "chordoid" or "sarcomatoid" morphology. Our findings suggest that UC with myxoid stroma/chordoid features shows characteristic expression of luminal and basal markers and different prognosis according to the morphologic pattern spectrum.

Prostate Cancer: Update on Grading and Reporting

The Gleason scoring system and Grade Group systems facilitate accurate grading and reporting of prostate cancer, which are essential tasks for surgical pathologists. Gleason Pattern 4 is critical to recognize because it signifies a risk for more aggressive behavior than Gleason Pattern 3 carcinoma. Prostatic adenocarcinoma with radiation or androgen therapy effect, with aberrant P63 expression, or with Paneth cell-like differentiation represent pitfalls in prostate cancer grading because although they display architecture associated with aggressive behavior in usual prostatic adenocarcinoma, they do not behave aggressively and using conventional Gleason scoring in these tumors would significantly overstate their biologic potential.

Sarcomatoid Urothelial Carcinoma With Myxoid Stroma: A Case Report and Diagnostic Approach

Bladder cancer is the seventh most common cancer in the world. Urothelial carcinoma is the most common type of bladder cancer. Other subtypes like squamous cell carcinoma and adenocarcinoma are less common. Urothelial carcinoma has a propensity for divergent differentiation. Sarcomatoid carcinoma is one of the variants of urothelial carcinoma. It is an aggressive tumor that presents at an advanced stage and has a poorer prognosis than conventional urothelial carcinoma. Therefore, identifying this variant histology is important clinically. The sarcomatoid component in sarcomatoid carcinoma can be spindle cell (not otherwise specified), myxoid, pseudoangiosarcomatous, and undifferentiated sarcoma like. Myxoid stroma in sarcomatoid urothelial carcinoma has been described but reported very rarely. We present a case of sarcomatoid urothelial carcinoma with myxoid stroma along with a review of the diagnostic approach to myxoid spindle cell lesions of the urinary bladder.

Unusual Faces of Bladder Cancer

Simple Summary

The spectrum of architectural and cytological findings in UC is wide, although transitional cell carcinoma, either papillary or flat, low- or high-grade, constitutes the majority of cases in routine practice. Some of these changes are just mere morphological variations, but others must be recognized since they have importance for the patient. The goal of this review is to compile this histological variability giving to the general pathologist a general idea of this morphological spectrum in a few pages. The review also updates the literature focusing specifically on the morphological and immunohistochemical clues useful for the diagnosis and some selected molecular studies with prognostic and/or diagnostic implications.

Abstract

The overwhelming majority of bladder cancers are transitional cell carcinomas. Albeit mostly monotonous, carcinomas in the bladder may occasionally display a broad spectrum of histological features that should be recognized by pathologists because some of them represent a diagnostic problem and/or lead prognostic implications. Sometimes these features are focal in the context of conventional transitional cell carcinomas, but some others are generalized across the tumor making its recognition a challenge. For practical purposes, the review distributes the morphologic spectrum of changes in architecture and cytology. Thus, nested and large nested, micropapillary, myxoid stroma, small tubules and adenoma nephrogenic-like, microcystic, verrucous, and diffuse lymphoepithelioma-like, on one hand, and plasmacytoid, signet ring, basaloid-squamous, yolk-sac, trophoblastic, rhabdoid, lipid/lipoblastic, giant, clear, eosinophilic (oncocytoid), and sarcomatoid, on the other, are revisited. Key histological and immunohistochemical features useful in the differential diagnosis are mentioned. In selected cases, molecular data associated with the diagnosis, prognosis, and/or treatment are also included.

Histological Characterization of Feline Bladder Urothelial Carcinoma

Urothelial (transitional cell) carcinoma (UC) is the most common type of bladder cancer in humans, dogs and cats, although the incidence in cats is comparatively low. This retrospective study details the histopathological features of UC of the urinary bladder in 38 samples from 35 cats. Of the 38 samples, eight had a papillary architecture and in nine the tumour cells formed tubular or acinar structures. Tumour cell invasion of the bladder wall varied from confinement within the lamina propria or submucosa to transmural or extending to the serosa. The tumour stroma varied from sparse to abundant, with a scirrhous, myxomatous or mucinous appearance in eleven cases, three cases and one case, respectively. The degrees of tumour cell necrosis and inflammation were highly variable. We confirm that the histopathological features of bladder UC in cats have many similarities to the corresponding tumours in dogs and humans.

Urothelial carcinoma of the bladder with abundant myxoid stroma: A case report and literature review

INTRODUCTION

Abundant myxoid stroma rarely occurs in urothelial carcinomas (UCs). We report an 83-year-old woman with UC of the urinary bladder with abundant myxoid stroma. We summarized the clinicopathological features, immunophenotype, diagnosis, and differential diagnosis of this type of bladder cancer, in order to improve the understanding of surgeons and pathologists.

PATIENT CONCERNS

An 83-year-old female presented with hematuria and frequent micturition, without odynuria, hypogastralgia, or fever.

DIAGNOSIS

The computed tomography scan demonstrated extensive tumors in the anterior wall of the bladder and a soft tissue shadow anterior to the sacrum. Cystoscopy showed massive wide-based tumors located on the anterior and lateral walls of the bladder, with no tumor involving the bladder neck. Multiple punch biopsies were performed, the histologic evaluation of which revealed a poorly differentiated invasive UCs with myxoid stroma.

INTERVENTIONS

The patient underwent a laparoscopic radical cystectomy and cutaneous ureterostomy.

OUTCOMES

The patient discharged without any complications. Histologic evaluation revealed an invasive UC; the most prominent feature was an abundant myxoid stroma that covered approximately 80% of the lesion and the tumor cells were arranged in cords, small nests, or a sheet-like structure. Immunohistochemically, the tumor cells were positive for CK19, CK20, VEGF, EGFR, p63, 34βE12, MUC1, GATA3, uroplakin3, and TopII (rate = 15%), while the Ki-67 proliferation index was 10%. The myxoid stroma in the mesenchyme stained positively with AB-PAS and colloidal iron, and some tumor cells stained positive for colloidal iron. Considering the histologic, histochemical, and immunohistochemical findings, a diagnosis of UC with abundant myxoid stroma was made. After surgery, the regular follow-up was continued in clinic, and there was no recurrence for 2 years.

CONCLUSION

Morbidity associated with UC with abundant myxoid stroma is very low. The diagnosis mainly depends on histopathological and immunohistochemical findings.

A Fibromyxoid Stromal Response is Associated with Muscle Invasion in Canine Urothelial Carcinoma

Canine urothelial carcinoma (UC) is the most common type of cancer of the lower urinary tract and tends to affect elderly neutered female dogs, with a high predisposition for Scottish terriers. Tumour stroma, inflammation and necrosis are poorly characterized in canine UC and their role as prognostic factors is unknown. The aims of this study were to (1) assess histologically 381 canine UCs, with emphasis on myxoid tumour stroma, inflammation and necrosis and (2) assess possible associations between these features and the available epidemiological data as well as bladder wall muscle invasion. In 103 of 381 (27%) cases, the stroma was mixed collagenous and myxoid (fibromyxoid), which was strongly associated with invasive growth of muscle (P <0.0001). Peritumoural and intratumoural inflammation was present in 308 of 345 (89%) and 287 of 381 (75%) cases, respectively, and was mostly mild and lymphoplasmacytic. One hundred and fifteen of the 381 (30%) cases showed a variable eosinophilic inflammation and 58 of 381 (15%) presented with formations of one or several lymphoid follicles. Twenty-four percent (91 of 381) of cases had tumour necrosis, which was typically mild. In 83 of 91 (91%) cases, the necrosis was comedo-like. Moderate to severe tumour necrosis was associated with the presence of moderate to predominant fibromyxoid tumour stroma (P <0.02). The results of this study indicate that fibromyxoid stroma is common in canine UC and is a strong indicator for invasive growth of muscle, which is consistent with a poor prognosis. Based on histomorphology, tumour necrosis in canine UC is best described as comedonecrosis.

High Grade Mucinous Urothelial Carcinoma of the Renal Collecting System: A Case Report

High grade mucinous urothelial carcinoma is a rare pathological variant. There is still controversy as to its nomenclature and classification. We report the case of a 64 year old female with history of pelvic pain who was incidentally discovered to have a left upper pole renal mass. Left nephroureterectomy was performed and histopathological examination revealed high grade mucinous urothelial carcinoma. Accurate diagnosis of this distinct pathological entity will allow for better understanding of phenotypic behavior and inform best treatment strategies.

Update for the practicing pathologist: The International Consultation On Urologic Disease-European association of urology consultation on bladder cancer

The International Consultations on Urological Diseases are international consensus meetings, supported by the World Health Organization and the Union Internationale Contre le Cancer, which have occurred since 1981. Each consultation has the goal of convening experts to review data and provide evidence-based recommendations to improve practice. In 2012, the selected subject was bladder cancer, a disease which remains a major public health problem with little improvement in many years. The proceedings of the 2nd International Consultation on Bladder Cancer, which included a 'Pathology of Bladder Cancer Work Group,' have recently been published; herein, we provide a summary of developments and consensus relevant to the practicing pathologist. Although the published proceedings have tackled a comprehensive set of issues regarding the pathology of bladder cancer, this update summarizes the recommendations regarding selected issues for the practicing pathologist. These include guidelines for classification and grading of urothelial neoplasia, with particular emphasis on the approach to inverted lesions, the handling of incipient papillary lesions frequently seen during surveillance of bladder cancer patients, descriptions of newer variants, and terminology for urine cytology reporting.

Mucinous urothelial carcinoma of the renal pelvis

Urothelial carcinoma with abundant myxoid stroma is a newly-described and extremely rare entity. Since only very few cases have been reported, there is no consensus on its nomenclature. Microscopic examination revealed invasive urothelial carcinoma with widespread low-grade noninvasive areas. There were focal invasive areas in the neighborhood of the renal parenchyma. Malignant urothelial tumor/cell groups localized in the stroma had abundant myxoid/mucinous background in the invasive areas. The cytoplasm of the tumoral cells was more eosinophilic in these areas and the cells formed small groups and cords. Histochemically, PAS and Alcian Blue were positive in the cytoplasm of the tumoral cells and in the stroma while negative in the non-mucinous areas. Immunohistochemically, the tumoral cells of the mucinous invasive areas diffusely expressed MUC1 and MUC2. We discuss the origin of the mucinous/myxoid stroma, the tumor’s nature and its nomenclature with histochemical and immunohistochemical features.

A synchronous occurrence of urothelial carcinoma with abundant myxoid stroma and inverted papilloma of the urinary bladder

Abundant myxoid stroma rarely occurs in urothelial carcinomas, and may cause diagnostic challenges when cells with eosinophilic cytoplasm forming nests and cords in a myxoid background are seen, particularly in the absence of typical carcinomatous appearance. Microscopic examination of transurethral resection specimen of a 71-year-old male patient revealed non-cohesive oval or elongated tumor cells with eosinophilic cytoplasm arranged in cord-like filigree pattern in an abundant myxoid stroma. Immunohistochemically the tumor was positive for cytokeratin 7, cytokeratin 20, and 34BE12. About 90 to 100% nuclear staining was observed with p63, p53, and Ki-67. A second neoplasm with a flat overlying urothelial epithelium and a complete inverted cellular growth pattern was also noted. The neoplasm exhibited less than 2% and 10% nuclear staining with Ki-67 and p53, respectively. Considering histological, histochemical, and immunohistochemical findings, a diagnosis of synchronous urothelial carcinoma with abundant myxoid stroma and inverted papilloma was made.

Invasive low-grade papillary urothelial carcinoma: a clinicopathologic analysis of 41 cases

Typically in invasive papillary urothelial carcinoma both the overlying papillary and the invasive components are high grade. We describe a series of patients with invasive low-grade papillary urothelial carcinoma (LPUC) in which both the noninvasive and invasive components are low grade. A retrospective search from The Johns Hopkins Surgical Pathology Database and consult cases from one of the author's files from 1998 to 2011 found 54 cases of invasive LPUC, excluding the more common, unique, and already well-characterized nested variant of urothelial carcinoma. Slides were available for 41 cases and formed the basis of the current study. The mean patient age was 68.4 years, with a male predominance. The specimens consisted of 37 bladder biopsies, 1 renal pelvis biopsy, 1 cystoprostatectomy specimen, 1 nephrectomy specimen, and 1 nephroureterectomy specimen. In all cases, invasion was limited to the superficial lamina propria above the muscularis mucosae. None of the histologic features correlated with tumor recurrence. Follow-up information was available for 73% of cases, with an average time interval of 49 months. Recurrent tumor was identified in 10/29 (34%) cases; however, 34% of cases without recurrence had limited follow-up (<24 mo). Three patients showed progression in tumor grade, and 3 additional patients progressed in both grade and stage (60% stage/grade progression). Four patients developed recurrence with ureteral noninvasive LPUC (2 in the bladder and 2 in the ureter). All are alive without disease. As this lesion is being increasingly recognized, larger studies are needed to determine whether invasion arising in LPUC is a significant risk factor for future disease.

Papillary Urothelial Carcinoma of the Bladder With Exuberant Pseudosarcomatous Stromal Reaction Following Radiation Therapy

An 82-year-old man, with 6-year history of radical prostatectomy followed by radiotherapy performed for prostatic carcinoma, underwent transurethral resection of a papillary tumor of the bladder lateral walls. Histologically, the lesion displays 2 distinct components: epithelial and stromal. The epithelial component was composed of a noninvasive papillary urothelial carcinoma, predominantly low grade and focally high grade. The stromal component exhibited extensive myxoid changes with increased cellularity but lacking cellular atypia and mitoses. The epithelial component was immunoreactive for pan-cytokeratins and negative for smooth muscle actin (SMA) and vimentin. The stromal component exhibited focal positivity for pan-cytokeratins and SMA, and diffuse immunoreactivity for vimentin. The ki67 reached 70% in the epithelial component and 20% in the stromal component. Papillary intraurothelial carcinoma following radiotherapy may be associated with pseudosarcomatous stromal proliferation. The clinical history and the lack of cellular atypia and mitoses point toward the correct diagnosis.