Urinary Diversion: Ileal Conduit to Neobladder

Urinary diversion: options, patient selection, and outcomes.

Patients and their urologists are quite rightly concerned about the possibility of neoplastic change within intestinal segments transposed to the lower urinary tract. This fear arises from the occurrence of latent adenocarcinoma arising from the urocolic anastomosis in approximately 10% of patients who underwent ureterosigmoidostomy in childhood. The present text provides an update of previous reviews and details work published since 1990 on epidemiological, experimental and clinical studies. Consideration of the collected evidence confirms the increased risk of colonic neoplasia following mixing of the faecal and urinary stream by ureterosigmoidostomy or its more recent variants. In contrast, the occurrence of tumours within transposed intestinal segments appears more likely to be related to the underlying urinary tract disease for which the surgery was performed rather than exposure of the intestinal mucosa to urine. This conclusion is, however, based on low level evidence and, despite the reassuring findings, caution is advised until more robust data are available to provide a confident risk assessment.

Tumour formation within intestinal segments transposed to the urinary tract

A handful of therapeutic procedures are used to treat malignancies of the urinary tract, most frequently intravesical immunotherapy or chemotherapy, but also neoadjuvant systemic chemotherapy. These treatment modalities produce morphological changes in the urothelium that can be mistaken for carcinoma; in particular, these therapies frequently mimic urothelial carcinoma in situ (CIS) urothelial dysplasia or true invasive neoplasia. Drugs such as mitomycin C used after transurethral resection of bladder tumour to reduce recurrences, bacillus Calmette–Guerin (BCG) intravesical immunotherapy to treat high-risk non-muscle-invasive bladder cancer and urothelial CIS and platin-based systemic chemotherapy to improve postcystectomy disease-specific survival are examples of therapy-related atypia seen in the urinary tract. To complicate the pathologist's life, a number of systemic drugs in use to treat other diseases, such cyclophosphamide, used to treat some autoimmune disorders or certain haematological malignancies or, in the case of anaesthetics, ketamine, used increasingly as an illegal recreational drug, may produce similarly relevant atypical changes in the urothelium, and therefore need to be differentiated from intraepithelial neoplasia. Other less frequent procedures, such as photodynamic and laser therapy or the newer gene therapy to treat urothelial neoplasia, remain experimental. An immunohistochemical approach to reactive urothelium versus carcinoma in situ using p53, cytokeratin 20 and CD44 is also valid in the post-therapy setting. The pathologist should be aware of these novelties, as he or she plays a crucial role in evaluating treatment efficacy, but at the same time needs to avoid misdiagnosing secondary atypia as intraepithelial neoplasia.

Iatrogenic changes in the urinary tract.

BLADDER TREATMENT: Immunotherapy and Chemotherapy

Most observations of the solar corona beyond 2 Rs consist of broadband visible light imagery from coronagraphs. The associated diagnostics mainly consist of kinematics and derivations of the electron number density. While the measurement of the properties of emission lines can provide crucial additional diagnostics of the coronal plasma (temperatures, velocities, abundances, etc.), these observations are comparatively rare. In visible wavelengths, observations at these heights are limited to total eclipses. In the VUV range, very few additional observations have been achieved since the pioneering results of UVCS. One of the objectives of the Full Sun Imager (FSI) channel of the EUI telescope on board the Solar Orbiter mission has been to provide very wide field-of-view EUV diagnostics of the morphology and dynamics of the solar atmosphere in temperature regimes that are typical of the lower transition region and of the corona. FSI carries out observations in two narrowbands of the EUV spectrum centered on 17.4 nm and 30.4 nm that are dominated, respectively, by lines of Fe IX/X (formed in the corona around 1 MK) and by the resonance line of He II (formed around 80 kK in the lower transition region). Unlike previous EUV imagers, FSI includes a moveable occulting disk that can be inserted in the optical path to reduce the amount of instrumental stray light to a minimum. FSI detects signals at 17.4 nm up to the edge of its FOV (7~Rs), which is about twice further than was previously possible. Comparisons with observations by the LASCO and Metis coronagraphs confirm the presence of morphological similarities and differences between the broadband visible light and EUV emissions, as documented on the basis of prior eclipse and space-based observations. The very-wide-field observations of FSI are paving the way for future dedicated instruments.

/pdf/beyond-the-disk-euv-coronagraphic-observations-of-the-1goetgei.pdf

Beyond the disk: EUV coronagraphic observations of the Extreme Ultraviolet Imager on board Solar Orbiter

Objective

 To investigate the long-term morphological changes in the intestinal segment used to create an orthotopic ileal neobladder.



Materials and methods

 Periodic endoscopy with biopsy of the ileal mucosa was performed in 90 patients 3–84 months after radical cystectomy and urinary diversion via an orthotopic neobladder. Three cold-cup biopsies were taken from each patient and mucosal specimens processed for light and electronic microscopy.



Results

 Early changes (up to 1 year after surgery) comprised a marked shortening of the villi with loss of microvilli. After 4 years, the prevalent finding was of flat, avillous epithelium that tended to stratify in some areas. The avillous areas were mixed with islets of villous mucosa. There was no dysplasia or malignancy in any of the 90 patients.



Conclusions

 Prolonged contact with urine elicited a biphasic response in the ileal mucosa, i.e. an early inflammatory phase, ascribed to the noxious action of urine, followed by a regressive phase in which the epithelium tended to assume a morphology similar to the urothelium. The atrophic changes were almost totally completed after 4 years, although areas with marked modifications alternated with others where the morphology was normal, even many years after surgery. Late changes in the ileal neobladder mucosa appear to be an expression of a functional adaptation of the mucosa to the new environment.

Structural and ultrastructural changes in ileal neobladder mucosa: a 7-year follow-up

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Parenti

Author Tools

Chat about Author

Papers

Beyond the disk: EUV coronagraphic observations of the Extreme Ultraviolet Imager on board Solar Orbiter

Structural and ultrastructural changes in ileal neobladder mucosa: a 7-year follow-up