Comparative genomic hybridization (CGH) of augmentation cystoplasties

Invasive poorly differentiated adenocarcinoma of the bladder following augmentation cystoplasty: a multi-institutional clinicopathological study

Augmentation cystoplasty is a surgical procedure used in the management of patients with neurogenic bladder. This procedure involves anastomosis of the bladder with gastrointestinal grafts, including portions of ileum, colon, or stomach. A rare but important complication of augmentation cystoplasty is the development of malignancy. The majority of malignancies arising in this setting have been described in case reports. A search for cases of non-urothelial carcinoma following augmentation cystoplasty was conducted through the urological pathology files of four major academic institutions. Ten cases were identified, including six cystoprostatectomy/cystectomy, two partial cystectomy, and two transurethral resection of bladder tumour specimens. The mean patient age at diagnosis was 47 years (range 27-87 years). The male:female ratio was 4:6. The tumours tended to present at an advanced stage; four cystoprostatectomy/cystectomy cases were categorised as pT3a, one was categorised as pT3b, and one was categorised as pT4a. Lymph node metastases were present in all cases which had lymph node excision (range 1-16 positive nodes per case). The majority of cases (90%) were predominantly characterised by a poorly differentiated adenocarcinoma with signet ring cell features. Other morphological features included mucinous features (30%), plasmacytoid features (20%), enteric/villous architecture (10%), and large cell undifferentiated morphology (10%). This is the largest study to date on the clinicopathological features of invasive non-urothelial carcinoma of the bladder following augmentation cystoplasty. The tumours are typically poorly differentiated adenocarcinoma, with diffuse signet ring cell features, aggressive, and present at high stage. Further molecular characterisation may provide additional insights into the pathogenesis of this entity.

Transitional metaplasia in intestinal epithelium of rats submitted to intestinal cystoplasty and treatment with L -lysine

Purpose:

To evaluated the effects of L-lysine on the intestinal and urothelial epithelia in cystoplasty in rats.

Methods:

Twenty-eight 9-week-old rats were assigned to 4 groups: Group A (n=8) cystoplasty followed by administration of L-lysine (150 mg/kg body weight by gavage) for 30 weeks; Group B (n=8) cystoplasty + water for 30 weeks; Group C (n=6) L-lysine for 30 weeks; Group D (n=6) water for 30 weeks.

Results:

On histopathology with hematoxylin and eosin, mild to moderate hyperplasia transitional was observed in at the site of anastomosis in all animals submitted to cystoplasty (Groups A and B), but "transitional metaplasia" of the intestinal glandular epithelium was more accentuated in Group A (p=0.045). No inflammatory cells, dysplasia or abnormalities were observed. Staining with Alcian blue revealed a substantial reduction of goblet cells and mucins in the colon segment (Groups A and B).

Conclusion:

The administration of L-lysine to rats accelerated the development of transitional metaplasia in the epithelium of the colon segment in cystoplasty.

[Adenocarcinoma arising in an ileum segment of Scheele's ring 50 years after cystoplasty]

A 70 year-old woman visited our hospital complaining of macrohematuria. She had undergone augmentation ileocystoplasty for tuberculous bladder atrophy 50 years previously. CT and cystoscopy showed tumor at the ileovesical anastomosis. She underwent a partial cystectomy. The pathological diagnosis was adenocarcinoma of the ileal segment. Recurrence was observed with rapid progression. The patient died 8 months after the operation. In Japanese literature, 43 cases of carcinoma arising in augumented bladder have been reported. Average period to the diagnosis of the cancer from the ileocystoplasty is 33 years. The period of our case was 50 years, the longest in 43 cases.

Molecular characteristics of urothelial neoplasms in children and young adults: a subset of tumors from young patients harbors chromosomal abnormalities but not FGFR3 or TP53 gene mutations

Urothelial neoplasms in children and young adult patients are rare and hypothesized to have a lower rate of recurrence and progression than those of older adults. Because of their rarity, data regarding molecular abnormalities in these tumors are limited. We studied molecular characteristics of urothelial neoplasms from patients under age 30 years using UroVysion fluorescence in situ hybridization (chromosomes 3, 7, 17, and 9p21) and DNA mutational analysis for the FGFR3 and TP53 genes. Seventeen tumors were identified in patients 6-26 years of age, including low-grade papillary urothelial carcinoma (n=10), high-grade papillary urothelial carcinoma (n=5), urothelial papilloma (n=1), and papillary urothelial neoplasm of low malignant potential (n=1). No tumor demonstrated mutation of FGFR3 or TP53. Chromosomal abnormalities were detected only in patients aged ≥19 years: two low-grade urothelial carcinomas had loss of 9p21 as a sole chromosomal abnormality and three high-grade urothelial carcinomas had other or multiple chromosomal abnormalities. Under age 19 years, no tumor showed molecular abnormalities with either method (five low-grade papillary urothelial carcinomas and one each of high-grade papillary urothelial carcinoma, papillary urothelial neoplasm of low malignant potential, and urothelial papilloma). Our results support the idea that mutations of the FGFR3 and TP53 genes are rare or absent in urothelial neoplasms of young patients. In contrast, chromosomal abnormalities detected by UroVysion fluorescence in situ hybridization are sometimes present in patients above 19-20 years of age. This finding supports the recently proposed hypothesis that an age of 19-20 years separates distinct molecular pathways of urothelial carcinogenesis.

Identification of prefoldin amplification (1q23.3-q24.1) in bladder cancer using comparative genomic hybridization (CGH) arrays of urinary DNA

BACKGROUND

Array-CGH represents a comprehensive tool to discover genomic disease alterations that could potentially be applied to body fluids. In this report, we aimed at applying array-CGH to urinary samples to characterize bladder cancer.

METHODS

Urinary DNA from bladder cancer patients and controls were hybridized on 44K oligonucleotide arrays. Validation analyses of identified regions and candidates included fluorescent in situ hybridization (FISH) and immunohistochemistry in an independent set of bladder tumors spotted on custom-made tissue arrays (n = 181).

RESULTS

Quality control of array-CGH provided high reproducibility in dilution experiments and when comparing reference pools. The most frequent genomic alterations (minimal recurrent regions) among bladder cancer urinary specimens included gains at 1q and 5p, and losses at 10p and 11p. Supervised hierarchical clustering identified the gain at 1q23.3-q24.1 significantly correlated to stage (p = 0.011), and grade (p = 0.002). The amplification and overexpression of Prefoldin (PFND2), a selected candidate mapping to 1q23.3-q24.1, correlated to increasing stage and tumor grade by means of custom-designed and optimized FISH (p = 0.013 and p = 0.023, respectively), and immunohistochemistry (p ≤0.0005 and p = 0.011, respectively), in an independent set of bladder tumors included in tissue arrays. Moreover, PFND2 overexpression was significantly associated with poor disease-specific survival (p ≤0.0005). PFND2 was amplified and overexpressed in bladder tumors belonging to patients providing urinary specimens where 1q23.3q24.1 amplification was detected by array-CGH.

CONCLUSIONS

Genomic profiles of urinary DNA mirrowed bladder tumors. Molecular profiling of urinary DNA using array-CGH contributed to further characterize genomic alterations involved in bladder cancer progression. PFND2 was identified as a tumor stratification and clinical outcome prognostic biomarker for bladder cancer patients.

Composite urinary reservoir in dogs: histological findings

PURPOSE

This animal study was designed to investigate whether the composite urinary reservoir might lessen the premalignant histological alterations observed after bladder augmentation performed with a gastric segment or large bowel.

MATERIALS AND METHODS

Composite urinary reservoirs were created using gastric and colonic segments simultaneously in 8, 3-month-old female beagle dogs by augmenting half the native bladder. Two dogs with gastrocystoplasty and 2 with colocystoplasty served as controls. Biopsies were taken from the native bladder, and the gastric and colonic segments at augmentation, and endoscopically 4 and 8 months postoperatively. The dogs were sacrificed and open biopsied 12 months postoperatively. Tissue specimens were examined with routine hematoxylin and eosin, reaction and immunohistological staining for PCNA.

RESULTS

At the creation of composite reservoir and gastrocoloplasty or colocystoplasty all specimens showed normal histology. At 12 months postoperatively dysplasia was found in 1 gastric segment, 2 native bladders and 3 colonic segments in the composite reservoir group. There was a single carcinoma in situ in 1 gastric segment in the composite reservoir group. In the control groups 1 colonic segment and 1 native bladder dysplasia were detected at the end of 12-month followup. There was an in situ carcinoma in 1 gastric segment in the composite reservoir.

CONCLUSIONS

A composite reservoir did not decrease premalignant changes in dogs during 12 months of followup. Laboratory investigations, molecular studies and longer followup are needed to approach the question of early malignant alterations after augmentation cystoplasty in animals and patients.

Molecular markers for detection, surveillance and prognostication of bladder cancer

Many markers for the detection of bladder cancers have been tested and almost all urinary markers reported are better than cytology with regard to sensitivity, but they score lower in specificity. Currently molecular and genetic changes play an important role in the discovery of new molecular markers for detection, prognostication and surveillance. The purpose of this review is to highlight the most important urinary molecular biomarker developments that have been studied and reported recently. In the current review we have summarized the most recent and relevant published reports on molecular urinary markers. The results of this review show that the first generation of urinary markers did not add much to urinary cytology. The current generation of markers is better, but additional clinical trials are needed. Our knowledge of molecular pathways in bladder cancer is growing and new methods of marker development emerge, but the perfect marker is still to be found. Currently, there are not clinically usable molecular markers that can guide us in diagnosis or surveillance, nor guide us in lowering the frequency of urethrocystoscopy in bladder cancer.

Identification of early p53 mutations in clam ileocystoplasties using restriction site mutation assay

OBJECTIVES

Because a risk of cancer arising in enterocystoplasties exists, it is necessary to identify which patients are most at risk of tumor formation. The aim of this study was to determine whether rare mutated p53 sequences were more common at the enterovesical anastomosis than in the bladder remnant in patients with a clam ileocystoplasty using the restriction site mutation (RSM) assay.

METHODS

DNA was extracted from endoscopic biopsies obtained from the ileovesical anastomosis and native bladder remnant (control specimens) of 38 patients with a clam ileocystoplasty. The RSM assay was used to study five known hotspots for mutations of the p53 gene using the restriction enzymes Hha I (codon 175), Taq I (codon 213), Hae III (codon 249/250), and Msp I (codons 248 and 282). The mutational events of p53 were confirmed by sequencing the undigested mutated polymerase chain reaction products identified by RSM analysis.

RESULTS

We found p53 mutations at the ileovesical anastomosis in 7 of the 38 patients. The mutations were observed at codon 213 (n = 1), codon 248 (n = 3), and codon 250 (n = 3). No p53 mutations were detected in any control specimen.

CONCLUSIONS

The ileovesical anastomosis is genetically unstable in patients with a clam ileocystoplasty. The p53 mutations identified by the RSM assay at the enterovesical anastomosis could possibly be used as markers of genetic instability to identify patients at risk of developing a tumor. Prospective, randomized longitudinal studies are required to substantiate this hypothesis.