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

Carcinoma arising in ileal conduit or orthotopic ileal neobladder reconstruction: A 20-year single institute experience

CONTEXT

Carcinomas found in urinary diversion specimens are uncommon, particularly new primary tumours. New primary tumours primarily occur when the large intestine is utilised, whereas the occurrence is infrequent with the use of the ileum. These tumours include both the recurrence of primary malignancy or the development of a new primary malignancy originating from the small intestine.

DESIGN

A search was performed within the pathology laboratory system to identify cases of malignancies involving ileal conduit/reconstruction from 2002 to 2022. Data on demographics, clinical details, pathology and management was recorded.

RESULTS

A total of 13 male patients, with a mean age of 67 years (range = 49-81 years) were included in the study. The initial procedure performed included cystoprostatectomy (n = 10, including one case with right nephroureterectomy) and cystectomy (n = 3, including one case for bladder exstrophy) for initial diagnoses including urothelial carcinoma (n = 11; conventional, 6; sarcomatoid, 1; glandular 1; plasmacytoid, 1; micropapillary, 2) and adenocarcinoma (n = 1). The initial management included radical surgery with neoadjuvant chemotherapy/immunotherapy (n = 1), adjuvant chemotherapy (n = 3), intravesical adjuvant BCG (n = 2) and intravesical adjuvant chemotherapy (n = 1). Malignancies in ileal conduit or orthotopic ileal neobladder included recurrent urothelial carcinoma (n = 10) and new secondary adenocarcinomas (n = 3), which developed as early as 3 months (usually recurrence) and up to 13, 33 and 45 years (new primary malignancy) following primary resection.

CONCLUSIONS

Utilising the ileum as conduit/neobladder presents a viable alternative for urinary diversion with a reduced malignancy risk compared to using a segment of the large intestine. However, there remains a potential for malignancy, either tumour recurrence or a new primary malignancy. In our study, tumour recurrence occurred up to 4 years following the initial diagnosis and the development of a new primary malignancy occurred up to 45 years after the initial diagnosis. Consequently, it is crucial to prioritise long-term follow-up for these patients undergoing this procedure.

Long-term complications arising from bowel interposition in the urinary tract

After radical cystectomy or pathologies affecting the ureter(s), bowel segments can be employed to restore the natural urine flow or to create an external urinary diversion. Nevertheless, the interposition of bowel segments in the urinary tract is not devoid of complications. In fact, bowel's microstructure differs from the urothelium; specifically its mucosa is aimed at reabsorption, rather than storage. The aim of this paper is to revise the pathophysiology of complications related to bowel's mucosal properties. Those are: metabolic imbalance, malabsorption of vitamins, cholelitiasis, nephrolitiasis and infections. Their entity varies according to the segment used and to its length, which reflects the surface in contact with urine. Mostly, they occur on the long-term, but metabolic imbalances might occur soon after surgery as well.

Reprogramming of the human intestinal epigenome by surgical tissue transposition

Extracellular cues play critical roles in the establishment of the epigenome during development and may also contribute to epigenetic perturbations found in disease states. The direct role of the local tissue environment on the post-development human epigenome, however, remains unclear due to limitations in studies of human subjects. Here, we use an isogenic human ileal neobladder surgical model and compare global DNA methylation levels of intestinal epithelial cells pre- and post-neobladder construction using the Infinium HumanMethylation450 BeadChip. Our study is the first to quantify the effect of environmental cues on the human epigenome and show that the local tissue environment directly modulates DNA methylation patterns in normal differentiated cells in vivo. In the neobladder, the intestinal epithelial cells lose their tissue-specific epigenetic landscape in a time-dependent manner following the tissue’s exposure to a bladder environment. We find that de novo methylation of many intestine-specific enhancers occurs at the rate of 0.41% per month (P < 0.01, Pearson = 0.71), while demethylation of primarily non-intestine-specific transcribed regions occurs at the rate of −0.37% per month (P < 0.01, Pearson = −0.57). The dynamic resetting of the DNA methylome in the neobladder not only implicates local environmental cues in the shaping and maintenance of the epigenome but also illustrates an unexpected cross-talk between the epigenome and the cellular environment.

Radical cystectomy and orthotopic bladder substitution using ileum

Over the past decade, continent urinary diversion, especially orthotopic bladder substitutions, has become increasingly popular following radical cystectomy for bladder cancer. The ultimate goal of orthotopic bladder substitution is to offer patients the best quality of life, similar to that of patients with native bladders. To achieve that purpose, surgeons should be familiar with the characteristics of good candidates for neobladders, the possible intraoperative and postoperative problems related to the surgery, and the solutions to these problems. Postoperative surveillance and instructions given to the patients also contribute to successful, functional results. Here, we reviewed the indications, pitfalls, and solutions for orthotopic bladder substitutions and the patients' quality of life after surgery. When performed properly, orthotopic continent diversion offers good quality of life with few long-term complications. Therefore, we believe it is the best option for the majority of patients requiring cystectomy.

Insight into long-term histological, proliferative and apoptotic modifications in ileal orthotopic neobladder and conduit mucosa

Aims and background

To assess the long-term histological, apoptotic and proliferating alterations of the intestinal mucosa of ileal conduits and orthotopic neobladders.

Methods

Fifty patients (46 males, 4 females), aged 52–78 years, who underwent urinary diversion with either ileal orthotopic neobladder (group ON, 20 patients) or conduit (group IC, 30 patients) from 2001 to 2005, were included in this prospective study Ileal samples were collected during surgery (controls) and by random mucosal biopsies 6, 12, 24, 36 and 48 months later. Histological (villi height, crypt depth, eosinophil cell count), proliferation (Ki67 immunochemistry), and apoptotic (Bcl-2 immunochemistry TUNEL) parameters were assessed.

Results

During the 4-year follow-up, we recorded progressive villi area, height and crypt depth reduction, mucosa flattening, and inflammatory and eosinophilic infiltration. Villi height: crypt depth ratio showed a statistically significant difference ( P <0.05) between the two groups from the 6th month. Dysplasia, metaplasia, and neoplasia were not observed. Bcl-2 values showed a progressive increase until 24 months in group ON and 12 months in group IC, followed by a decline thereafter. Ki-67 values showed a progressive increase after 6 months in group ON and an increase until 24 months followed by a decline thereafter in group IC. TUNEL showed two peaks, at 24 and 48 months.

Conclusions

Histological adaptation was revealed in both groups, with statistically significant differences in favor of orthotopic substitution. Proliferative and apoptotic pathways are implicated as demonstrated by relevant modifications of Bcl-2, Ki-67 and TUNEL, in accord with the histological adaptation.

Tubular adenoma with high-grade dysplasia in the ileal segment 34 years after augmentation ileocystoplasty: report of a first case

Neoplasms of the urinary bladder following augmentation ileocystoplasty are rare. We present the case of a 39-year-old male with a tubular adenoma with high-grade dysplasia in the ileal segment 34 years after augmentation ileocystoplasty to enlarge a post-chemoradiation-induced shrunken bladder. He presented with gross hematuria. Cystoscopy revealed a papillary tumor at the site of ileovesical anastomosis, and transurethral resection was performed. Histologic examination revealed a tubular adenoma with high-grade dysplasia. There are only two previous reports of tubulovillous adenoma in ileal segment after ileocystoplasty, both without high-grade dysplasia. Our observation supports the hypothesis that an ileal neobladder may undergo all the morphologic and molecular changes observed in the development of gastrointestinal adenocarcinoma. Therefore, patients who had an ileal neobladder created should be closely followed.

Urinary diversion: options, patient selection, and outcomes

Improved survival following radical cystectomy for bladder cancer as a result of advancements in combination chemotherapy and surgical technique has resulted in a philosophical change in the surgeon's approach to urinary diversion selection. Aims have evolved from the mere diversion of urine to a functional bowel conduit such as an ileal conduit or ureterosigmoidostomy, to providing the optimal diversion for the patient's quality of life. While quality of life is important, one must also consider the stage of cancer and individual patient comorbidities. Which diversion provides the best local cancer control, the lowest potential for complications (short and long term), and the easiest emotional adjustment in lifestyle while still allowing the timely completion of chemotherapy and therapeutic goals? A multidisciplinary approach to diversion selection that includes the patient, the medical oncologist, radiation oncologist, internist, and surgeon is ideal. We describe the three most commonly used types of diversions today, including conduits, continent cutaneous reservoirs, and orthotopic urethral diversions, as well as issues relative to patient selection and functional outcomes in patients undergoing radical cystectomy for the treatment of bladder cancer.

Entérocystoplastie de substitution chez l'homme (Hautmann exclu) : principes et applications techniques

Orthotopic urinary reservoir using a bowel segment has become the most favoured form of diversion after radical cystectomy. Ideal neobladder has to (i) store the urine with a low pressure bladder substitute, (ii) protect the upper urinary tract and (iii) provide a better quality of life enabling volitional voiding. A lot of techniques have bee described to construct a reservoir, however, all of them are based on the principle of intestinal loop detubulation. Many intestinal segments have been used, but ileum seems to be preferred in Europe. The upper urinary tract is mainly protected by a low neobladder pressure, rather than an additional antireflux flap-valve-type implantation technique which may increase the risk of uretero-enteric stricture. No significant difference in functional outcome can be observed among the several techniques. In selected cases, orthotopic bladder replacement is well tolerated and feasible and appears to be the gold standard after cystectomy.

Adenocarcinoma of ileal neobladder 20 years after cystectomy

We present the case of a 67-year-old man with adenocarcinoma of the ileal neobladder 20 years after radical cystoprostatectomy for Stage pT2 transitional bladder cell cancer. A MEDLINE research revealed 9 other cases of the development of a neoplasm in the ileal part of an ileocystoplasty. This observation supports the hypothesis that in an ileal neobladder morphologic and molecular changes can be observed similar to those in the development of colorectal carcinoma. Patients who had an ileal neobladder created are at risk of glandular malignancy and should be closely followed up.

Tumour formation within intestinal segments transposed to the urinary tract

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.

Histopathologic changes in the mucosa of ileal orthotopic neobladder--findings in 24 patients followed up for 5 years

OBJECTIVE

To evaluate changes occurring in the mucosa of the neobladder over a period of 60 months in 24 patients with orthotopic ileal neobladder.

MATERIALS AND METHODS

A total of 36 male patients have undergone radical cystoprostatectomy and received an orthotopic ileal neobladder in our hospital during the last 10 years; 24 of these patients, all of whom completed a follow-up period of 60 months, are included in this study. All cases underwent a biopsy of the ileal mucosa at the time of surgery and their neobladder mucosa was then biopsied at 6, 12, 24, 36 and 60 months. The specimens were stained with hematoxylin-eosin in order to examine the changes in the thickness of the mucosa and its villi. Sections were also stained with Alcian blue and periodic acid-Schiff in order to determine the number of goblet cells. A morphometric scoring system was created to quantify the change in villi size.

RESULTS

The mean thickness of the ileal mucosa at the initial biopsy was 270.9 +/- 35.9 microm and displayed a continuous decrease at all of the subsequent biopsies. The number of luminal goblet cells increased during follow-up. Villus atrophy was found to be a continuous process during follow-up. No dysplasia or malignancy was detected in any of the biopsies.

CONCLUSION

During a follow-up period of 5 years, there were no neoplastic changes in our patients, but instead a protective response of the mucosa to its new environment was observed.

Urinary diversion: ileal conduit to neobladder

PURPOSE

The goals of urinary diversion have evolved from simply diverting the urine through a conduit to orthotopic reconstruction, which provides a safe and continent means to store and eliminate urine with efforts to provide an improved quality of life. We address meaningful points that may help optimize clinical results in patients with an orthotopic bladder substitute.

MATERIALS AND METHODS

The review involved an objective evaluation of the basic science literature of functional, structural and physiological characteristics of gastrointestinal tissue as a substitute for bladder. Potential problems that may be associated with particular parts of the gut for use in reconstruction are discussed. We also summarize the clinical results and complications of orthotopic reconstruction.

RESULTS

In the last 10 years the paradigm for choosing urinary diversion has changed substantially: In 2002 all patients undergoing cystectomy were neobladder candidates. It is critically important to understand the phenomenon of maturation. The motor and pharmacological response of the implanted gut changes dramatically toward that of the bladder. Structural and ultrastructural changes in the ileal mucosa lead to a primitive epithelium similar to urothelium. The need for reflux prevention is not the same as in ureterosigmoidostomy conduit or continent diversion. Reflux prevention in neobladders is even less important than in a normal bladder. When using nonrefluxing techniques, the risk of obstruction is at least twice that after direct anastomosis. Kidney function is not impaired by diversion if stenosis is recognized and managed. Patient health status is more influenced by underlying disease than by diversion. Complications of neobladders are actually similar to or lower than the true rates after conduit formation, in contrast to the popular view that conduits are simple and safe. Some degree of nocturnal leakage is a consistent finding in most reports despite a technically sound operation. The precise pathogenesis of urinary retention requiring clean intermittent catheterization remains uncertain. There are new complications, such as neobladder rupture and mucous tamponade.

CONCLUSIONS

Orthotopic reconstruction has passed the test of time. In these patients life is similar to that in individuals with a native lower urinary tract. Until a better solution is devised orthotopic bladder reconstruction remains the best option for patients requiring cystectomy.

Ultrastructural basis for the efficiency of an ileal orthotopic neobladder 27 years after surgery

The morphological and functional basis of the excellent clinical outcome of ileal orthotopic neobladders are largely unknown. Only long-term follow-up studies will provide an adequate answer to this unsettled question. We have studied a patient who underwent this type of surgery over 27 years ago. Besides an important secretive adaptation we have found, at the ultrastructural level, that the monolayered epithelium does not show signs of true metaplasia and that changes had occurred in the intercellular junctions, namely that desmosomes are significantly increased. Although limited to a single case, these features, if confirmed by further observations, suggest a working hypothesis for the understanding of the definitive phenotypic adaptation of the ileal epithelium to the new aggressive environment.

Changes produced in the urothelium by traditional and newer therapeutic procedures for bladder cancer

A handful of traditional and newer therapeutic procedures, such as chemotherapy, immunotherapy, radiotherapy, photodynamic and laser treatment, and gene therapy, are used to treat epithelial malignancies of bladder origin. These treatment modalities, used either intravesically or systemically, produce morphological changes in the urothelial mucosa that can be mistaken for carcinoma. The pathologist must be able to separate toxic and drug related alterations from tumour related changes. The clinical history is usually invaluable in this assessment.

[Structural changes in the ileal mucosa of urinary conduits]

OBJECTIVES

To study the changes found in the terminal ileum mucosa in contact with urine in patients with skin ureteroileostomy following cystectomy due to infiltrant carcinoma of the bladder.

MATERIAL AND METHODS

21 biopsies of gut mucosa were performed in as many patients. Measurements included height of intestinal villi (average values -AV-: 350-300 mu), height of crypts (AV: 70-100 mu), crypt/villus ratio (AV: 0.2), goblet cells/enterocytes ratio, presence of lymphangiectasis and inflammatory infiltrate. Also the existence of lab changes were measured with ionogram and venous gasometry.

RESULTS

Mean age of patients was 65.2 years +/- 7.4 SD. Males 66.7%. Time of evolution with urinary by-pass was 59.5 months +/- 53.2 SD. Mean height of villi 178.2 mu +/- 70.2 SD, mean height of crypts 290.9 mu +/- 114.4 SD and mean crypt/villus ratio 4.2 +/- 9.2 SD. Submucous inflammatory infiltrate was mild in 57.1%, moderate in 23.8%, and severe in 19.0%. Only 2 cases had lymphangiectasis images. Goblet cells/enterocytes ratio was 3.3 +/- 1.3 SD. No correlation was seen between time of evolution of urinary by-pass with the various changes in gut mucosa or between degree of mucosal atrophy and existence of metabolic disorders.

CONCLUSIONS

Changes in the terminal ileum mucosa in patients with skin ureteroileostomy-like urinary by-pass are characterised by a marked atrophy of intestinal villi with increased crypt length, increased crypt/villus ratio and presence of mild-to-moderate inflammatory infiltrate. There is also an increase of goblet cells in detriment of enterocytes. All these changes are independent from the time of evolution of patients with urinary by-pass.

Bladder treatment. Immunotherapy and chemotherapy

The urinary bladder is affected by numerous treatments, including surgery, chemotherapy radiotherapy, photodynamic and laser therapy, and immunotherapy. The literature on therapy for bladder cancer is abundant but tends to offer little information concerning the tissue and cellular manifestations related to treatment. A variety of changes in urothelial cells may be seen on urinary cytology or biopsy. Therapy-associated cytologic abnormalities remain the most common cause of false-positive reports in urothelial cytology. Most pathologic changes are characterized by an exuberant inflammatory reaction, blood vessel abnormalities, and degenerative/regenerative urothelial atypia; none of these findings are diagnostic of the outcome of a specific therapy.

Orthotopic bladder augmentation and substitution

Orthotopic bladder augmentation or substitution using intestinal segments has become a standard procedure for many disorders that cause a loss of functional or anatomical bladder capacity. From the technical point of view, reservoir configuration by detubularizing the intestinal segments is the general practice. Various techniques exist, depending which types of segments and which techniques of ureteral implantation are used. Common problems include urinary incontinence, retention, metabolic disorders, and the possibility of secondary malignancies. As a result, research has been conducted into utilizing tissues other than intestine for bladder augmentation or substitution.

Isolation of human intestinal defensins from ileal neobladder urine

We describe the isolation of naturally occurring human intestinal defensins HD-5 and HD-6 from ileal neobladder urine and ileal mucosa. Using an antibody-based detection assay, we found multiple N-terminally processed forms of HD-5. The predominant HD-5 forms in tissue were longer than those in neobladder urine (amino acid (aa) 23-94 and 29-94 versus aa 36-94, 56-94 and 63-94) suggesting that Paneth cells store prodefensin that is processed to mature defensin during or after degranulation. Search for mature HD-6 yielded aa 69-100 as the predominant form in both sources. The ileal neobladder is a promising model to study human Paneth cell secretion.