China
Africa
Explore chapters and articles related to this topic
Bladder cancer
Published in Anju Sahdev, Sarah J. Vinnicombe, Husband & Reznek's Imaging in Oncology, 2020
The urothelium is the lining epithelium of the urinary collecting system, including the renal pelvis, ureters, bladder, and part of the urethra. Depending on the state of distension of the bladder, its thickness varies from three to seven cell layers. Under normal circumstances, these cells have a slow turnover rate, in the region of 3–6 months and will desquamate, but very few cells are seen in normal urine cytology specimens. When malignant transformation takes place, shedding of cells and haematuria will occur. Urothelial cancer can be classified according to its biological behavioural or morphological features. Behavioural features divide bladder cancer into non–muscle-invasive low-grade lesions or high-grade muscle-invasive lesions with risk of metastasis, and carcinoma in situ with propensity for muscle invasion. Non-invasive tumours can be divided into two morphological categories: papillary or flat. Carcinoma devoid of papillary structures is called carcinoma in situ (CIS) and is, by definition, high grade. Papillary lesions have delicate frond-like projections into the bladder lumen, non-papillary, or mixed papillary and infiltrative tumours. Papillary tumours are usually solitary intraluminal masses; non-papillary tumours may be infiltrative, ulcerative, or polypoid. These patterns of tumour growth are well demonstrated on imaging with CT and MR (Figure 16.1).
The kidneys
Published in C. Simon Herrington, Muir's Textbook of Pathology, 2020
Urothelial carcinoma (previously termed ‘transitional cell carcinoma’) can arise from the renal pelvis or calyces but occurs more commonly in the bladder. This tumour type is discussed in more detail in Chapter 17.
Abdomen and pelvis cases
Published in Lt Col Edward Sellon, David C Howlett, Nick Taylor, Radiology for Medical Finals, 2017
Faye Cuthbert, Amanda Jewison, Olwen Westerland
Management of the patient depends on the underlying cause and whether the renal function is compromised. If the renal function is compromised or there is suspicion of infection, the patient may require ureteric stenting. This involves passing a thin tube up the ureter to relieve the obstruction (usually cystoscopically) or inserting a percutaneous nephrostomy tube into the renal pelvicalyceal system to decompress the kidney. If malignancy is found, it will need to be staged and discussed at the urology MDT meeting in order to plan appropriate treatment. Transitional cell carcinoma can involve the urothelium any where in the renal tract. Smoking is an important risk factor.
Computational modeling of stretch induced calcium signaling at the apical membrane domain in umbrella cells
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2023
Amritanshu Gupta, Rohit Manchanda
The urothelium is the epithelial tissue lining the luminal surface of the urinary bladder. Its superficial layer comprises a specialised monolayer of polyhedral cells known as the umbrella cells (UCs), which form the interface between the urine and the underlying layers of the bladder wall. In addition to being a physical and protective barrier, the superficially placed UCs are involved in the transduction of various stimuli present in their external milieu, i.e., the urine (Khandelwal et al. 2009; Birder and Andersson 2013). These stimuli include mechanical stretch, change in temperature and alteration in the levels of chemical metabolites. UCs are highly polarised, having distinct apical and basolateral membrane domains designed to perform highly specialised and localised signaling functions (Khandelwal et al. 2009). More specifically, it is the apical membrane domain of the umbrella cell (UC) where key signal transduction activities are triggered.
Urothelium removal does not impact mucosal activity in response to muscarinic or adrenergic receptor stimulation
Published in Tissue Barriers, 2023
Christian Moro, Charlotte Phelps
The urothelium is one of the most effective permeability barriers to protect the body from the toxic substances of the urine, with a high transepithelial electrical resistance and ability to accommodate significant changes in the surface area during bladder filling.1 It is composed of three morphologically distinct cell layers, including basal cells, intermediate cells, and umbrella cells which cover the superficial apical surface. A range of mechanisms work together to effectively maintain the urothelial barrier. The glycosaminoglycan (GAG) layer lines the luminal surface of the urothelium and the basal membrane separates the urothelium from the underlying connective tissue layer. Approximately 90% of the apical surface of umbrella cells are covered by proteins called uroplakins, which function to maintain the integrity and strength of the urothelium, prevent ruptures during the filling phase, protect against toxic substances, and contribute to the low permeability of water and solutes.2 The GAG layer contributes to the maintenance of the barrier function from the harmful substances found in the urine, and damage to it can lead to exposure of urine to the underlying epithelial cells.3 In addition, each cell in the urothelium maintains tight junctions between adjacent cells,4 which forms a physical barrier that is impermeable to solvents in the urine.
Advances in the management of urothelial carcinoma: is immunotherapy the answer?
Published in Expert Opinion on Pharmacotherapy, 2021
Ariana L. Santopietro, David Einstein, Joaquim Bellmunt
Finally, more effective screening methods for urothelial carcinoma could have the potential to prevent the morbidity and mortality of advanced disease. While microscopic hematuria, even in high-risk populations, is too nonspecific to be used routinely for screening, novel biomarkers may address this issue. In bladder cancer, circulating tumor DNA (ctDNA) has shown to predict useful to monitor response or resistance to neoadjuvant chemotherapy or immunotherapy [99]. While existing urine- and blood-based biomarkers have not proved sufficiently sensitive and specific for use in screening, new technologies have significant potential: for example, the circulating DNA methylome has been used to detect early signs of RCC in blood and is much more sensitive than even circulating tumor DNA [100].