The role of multiple mucosal biopsies in the management of patients with bladder cancer

[Photodynamic diagnosis (PDD) in non-muscle invasive bladder cancer. Literature review]

Non-muscle invasive bladder cancer is one of the most prevalent and incident neoplastic conditions in the Western world. Its clinical management involves significant costs for health systems. Diagnosis and treatment are based on direct visualization of the disease and on detection of flat forms having no specific morphology and which are sometimes overlooked. Prognosis of NMIBC often depends on quality of transurethral resection and on early detection of undifferentiated flat forms. Cystoscopy using photosensitive substances such as 5-aminolevulinic acid (5-ALA) or hexyl aminolevulinic acid (HAL) achieves overdetection rates of 29 % for bladder neogrowths and 59% for carcinoma in situ. This overdetection ability results in an increased disease-free survival and a longer time to the first relapse. Increased costs resulting from use of these resources are compensated by a lower number of or delayed performance of cystectomies, resections, and instrumentations. It is concluded that PDD should be universally used, rather than in high risk patients only.that has been shown in both animal studies and human tumors.

Evaluation of Superficial Bladder Transitional-Cell Carcinoma by Optical Coherence Tomography

BACKGROUND AND PURPOSE

Optical coherence tomography (OCT) is a new modality that allows noninvasive examination of the internal structure of biological tissue in vivo with a spatial resolution of 10 to 15 microm. This study evaluated the clinical application of OCT to determine epithelial and subepithelial anatomic structure and invasiveness of bladder epithelial lesions.

MATERIALS AND METHODS

The OCT examination was performed with a 980-nm 10 mW superluminescent diode using a 2.7-mm-diameter optical fiber positioned cystoscopically. A total of 261 scans of 1.5 seconds' duration, which generated 200 x 200-pixel images, were performed on 87 areas in 24 patients at high risk of having transitional-cell carcinoma (TCC). Lesions, visually suspect, and normal areas were photographed, scanned, and biopsied. The scans were evaluated independently before comparison with histopathology findings.

RESULTS

Of the 87 areas, 29 of 36 visually suspect areas and 35 of 35 normal areas, were correctly diagnosed with OCT. Of the 16 areas with papillary TCC, all 16 were diagnosed correctly as tumor, and 9 of 10 were diagnosed correctly as invasive, including 6 with lamina propria invasion only. Papillary and flat tumors, carcinoma in situ, inflammation, chronic cystitis, and von Brunn's nests were scanned. Overall, OCT had a sensitivity of 100%, overall specificity of 89%, positive predictive value of 75%, and negative predictive value of 100%. The accuracy was 92%. The positive predictive value for invasion was 90%.

CONCLUSION

Optical coherence tomography is a simple, portable, promising modality for evaluation of bladder lesions and depth of tumor penetration. Further refinement of this technology may lead to the development of an optical surrogate for biopsy.

Intravesical bacille Calmette-Guérin in the treatment of carcinoma in situ or high-grade superficial bladder carcinoma after radiotherapy for bladder carcinoma

OBJECTIVE

To evaluate the effectiveness and tolerance of endovesical bacille Calmette-Guérin (BCG) after pelvic radiation therapy for bladder cancer in patients with recurrence as carcinoma in situ (CIS) and/or high-grade superficial bladder cancer.

PATIENTS AND METHODS

In a prospective study, 13 patients were treated with weekly instillations of 81 mg BCG Connaught for 6 weeks. for CIS and/or high-grade superficial bladder carcinoma. All had been treated previously with radical radiation therapy for bladder carcinoma.

RESULTS

Five patients had no recurrences and six patients retained their bladders, within a median follow-up of 74.5 months. Five patients progressed; two underwent radical surgery and are alive after 75 months of follow-up, and three died from the disease (two were high-risk surgical patients and one had metastatic disease). Another two patients died from intercurrent disease without bladder cancer. Eight patients were alive at a mean (SD range) follow-up of 85 (12, 65-97) months.

CONCLUSION

Intravesical BCG is useful for controlling CIS and/or high-grade superficial bladder carcinoma in irradiated bladders and has an acceptable local tolerance: more than a third of patients were free of disease and preserved their bladders. This proportion is acceptable in patients currently scheduled for cystectomy.

Clinical assessment of fluorescence cytoscopy during transurethral bladder resection in superficial bladder cancer

The prognosis of superficial bladder cancer in terms of recurrence and disease progression is related to bladder tumor multiplicity and the presence of concomitant "plane" tumors such as high-grade dysplasia and carcinoma in situ. This study in 33 patients aimed to demonstrate the role of fluorescence cystoscopy in transurethral resection of superficial bladder cancer. The method is based on the detection of protoporphyrin-IX-induced fluorescence in urothelial cancer cells by topical administration of 5-aminolevulinic acid. The sensitivity and the specificity of this procedure on apparently normal mucosa in superficial bladder cancer are estimated to be 82.9% and 81.3%, respectively. Thus, fluorescence cytoscopy is a simple and reliable method for mapping the bladder mucosa, especially in the case of multifocal bladder disease, and it facilitates the screening of occult dysplasia.

I parametri clinici, endoscopici e patologici nella valutazione delle potenzialità evolutive dei tumori superficiali della vescica: Clinical, endoscopic and pathological parameters in assessing the potential progression of superficial bladder tumours

Clinical, endoscopic and pathological assessment provides the classical factors of prevision for bladder tumours. The risk of recurrence is different among primary and recurrent tumours. The risk of recurrence for primary tumours is correlated to the number of neoformations at diagnosis and to the cystoscopy at three months. The risk of recurrence for recurrent tumours is correlated to the number of neoformations and the previous recurrence rate. It seems that the number of recurrences doesn't imply a higher risk of progression. The most important endoscopic parameters are: number, shape and size of neoformations, and appearance of the vesical mucosa. The most important pathological parameters are: growth pattern, grade, stage, histologic aspect of the vesical mucosa and invasion of lymphatic vessels. All these parameters are correlated to the risk of tumour progression for groups of patients but they cannot predict the fate of the individual case. The predictive value of these parameters could improve with a critical revision of the definitions of grade and stage.

Should random urothelial biopsies be taken from patients with primary superficial bladder cancer? A decision analysis. Members of the Dutch South-East Co-Operative Urological Group

OBJECTIVE

To evaluate whether it is worthwhile to implement routine random biopsies from the normal-looking urothelium in the management of patients with primary superficial bladder cancer.

PATIENTS AND METHODS

Two hypothetical management policies were compared, one of which incorporated random biopsies as an additional prognostic test. In the 'no-biopsy policy', all patients were treated with transurethral resection (TUR) alone, except for patients with a pT1G3 tumour who were treated with adjuvant prophylactic intravesical therapy. In the 'biopsy policy', the choice of treatment was influenced by the presence or absence of dysplastic urothelium in random biopsy specimens, except in patients with a pT1G3 tumour who received adjuvant treatment, irrespective of the result of random biopsies. Decision analysis was used to compare the outcome of these hypothetical policies with respect to the expected 3-year risks of recurrence and progression. Baseline data used in the analysis originated from a large unselected case series, prospectively documented in the Netherlands.

RESULTS

The 'biopsy policy' resulted in a 3 year risk of recurrence and a 3 year risk of progression of 52% and 11%, respectively. These 3 year risks were almost identical to the 'no-biopsy policy': 54% and 11%, respectively. In a sensitivity-analysis, the expected 3 year risks of recurrence as well as the expected 3 year risks of progression were found to remain similar with both policies, even with quite extreme assumptions favouring the 'biopsy policy'.

CONCLUSION

In view of the expected small difference in disease outcome between the two management policies, taking random biopsies of normal-looking urothelium at the time of the TUR has no practical value.

Dysplasia in normal-looking urothelium increases the risk of tumour progression in primary superficial bladder cancer

Random urothelium biopsies were taken at initial endoscopic surgery from 1001 patients with primary superficial bladder cancer. The clinical course of all the patients was assessed prospectively. Actuarial risks of recurrence and disease progression were determined for prognostic characteristics and comparisons were made using log-rank tests. The independent prognostic significance of concomitant intra-aurothelial dysplastic changes was examined with Cox's regression analyses. The 3-year risk of recurrence in patients with dysplasia and carcinoma in situ (CIS) in macroscopically normal-looking urothelium was only slightly higher than the risk in patients without dysplastic changes (56, 58 and 51%, respectively; P = 0.25). Concomitant dysplasia or CIS significantly increased the 3-year risk of disease progression (17 and 31%, respectively, versus 7%; P < 0.001). After adjustment for the effects of age, tumour stage, grade, size and multicentricity, the result of random biopsies had no prognostic significance regarding the risk of recurrence, but the detection of dysplasia or CIS increased the risk of progression by approximately 80%. This result suggests that random urothelium biopsies may be useful as an additional guide in defining therapy in primary superficial bladder cancer.

Superficial bladder carcinoma. Factors affecting the natural history

The natural history of superficial bladder carcinoma has an important bearing on the outcome of response to intravesical chemotherapy or immunotherapy. It may vary in different parts of the world, but it is essential that urologists know within their own practice how tumours respond to the initial transurethral resection. Many factors influence the natural history of superficial bladder carcinoma, and some, such as poor-grade, large tumour at presentation, smoking history, poor response to initial resection, and dysplasia or carcinoma in situ, should alert the urologist to introduce intravesical therapy at an early stage.

In vivo detection by microscopic chromocystoscopy of concurrent urothelial atypia in superficial bladder cancer

Microendoscopic observation of methylene blue-stained urothelial surfaces, so-called microscopic chromocystoscopy (MCC), was undertaken in 65 patients with superficial bladder cancer (Ta and T1) and its effectiveness in detecting concurrent urothelial dysplasia or carcinoma in situ was studied. A total of 166 biopsy samples were taken from 75 stained and 91 non-stained portions. Of 75 methylene blue-stained areas, 21 were judged to be abnormal (MCC-positive) by microscopic observation. Fourteen of these 21 MCC-positive areas (67%) were proven to be abnormal histologically, while 7 of 54 MCC-negative portions (13%) were histologically abnormal. Only 4 of 91 biopsies (4%) from non-stained mucosa were proven to have urothelial atypia. In per patient figures, 1 or more concurrent field changes were detected in 15 of 65 cases (23%). MCC contributed to the diagnosis in 10 of these 15 patients.

Interpretation of biopsies of "normal" urothelium in patients with superficial bladder cancer. MRC Superficial Bladder Cancer Sub Group

In the course of a Medical Research Council trial of intravesical chemotherapy, biopsies were taken from apparently normal bladder urothelium near to newly diagnosed superficial bladder cancers in 417 patients. Differences were noted in the rates at which histological features were described in different centres. To gain more information about the reproducibility of the pathological findings, a group of 6 pathologists (5 from the UK and 1 from the USA), all having a special interest in urological pathology, were asked to examine a representative sample of 92 slides. They were then asked to re-examine 30 of them after an interval of at least 6 months. At first examination and at re-examination the slides were assessed using a standard proforma. However, the definitions of the categories were left unspecified for the pathologists to use their own criteria. The 5 UK pathologists then met to establish a consensus view of each slide. The results indicated that: (1) The reporting of non-dysplastic changes varied so much between pathologists as to render it of little value to clinical practice. (2) There were wide variations between different pathologists in the reported incidence of dysplastic change. (3) On a second review the pathologists reproduced their own assessment on only 62% of occasions. (4) Even after discussion between pathologists there was no consensus on the diagnosis of mild as opposed to moderate dysplasia. Consensus was reached on all biopsies which showed either severe dysplasia or carcinoma in situ. (5) In adopting a policy of taking urothelial biopsies, urologists should be aware of the imprecision and lack of reproducibility in the interpretation of such biopsies. (6) Biopsies of cystoscopically normal urothelium may not be a useful guide in defining therapy.

The relationship of ABH(O) blood group antigen expression in intraepithelial dysplastic lesions to clinicopathologic properties of associated transitional cell carcinoma of the bladder

Paraffin-embedded, giant-step sections of 13 bladders with transitional cell carcinomas were stained with monoclonal anti-A or anti-B antibodies to investigate whether intraepithelial dysplastic lesions are related to obvious tumors. Normal and/or hyperplastic lesions were retained in only eight bladders; severe dysplasia and/or carcinoma in situ were found in all bladders except two. AB-antigen expression was retained in intraepithelial lesions of bladders with invasive carcinoma. Most intraepithelial lesions were AB-antigen negative in bladders with frequently recurrent tumors. In bladders with initially multiple tumors, AB-antigen expression was negative in almost one half of the intraepithelial lesions. Therefore, it appears likely that most multiple or recurrent bladder carcinomas arise from dysplastic cells in intraepithelial lesions which have acquired malignant potential; initially invasive tumors quickly develop from a limited lesion acquiring a high malignant potential without changes of cell phenotype in most intraepithelial lesions.

Grading in superficial bladder cancer. (1). Morphological criteria

In a prospective study on the grading of superficial papillary neoplasms of the bladder a distinction was made between tumours showing only increased cellularity without appreciable cellular and nuclear deviation (grade 1), tumours showing slight cellular variation (grade 2a), and tumours showing clear cytological deviation and a tendency to lose normal polarity (grade 2b). Ninety-one patients with a superficial tumour were followed up for a mean of 24 months. Grade 2a tumours recurred later and in fewer patients than grade 2b tumours. Progression was seen in 4% of grade 2a tumours and in 33% of grade 2b carcinomas. Adapting our results to the WHO grading system, we suggest that all tumours in this study defined as grades 1 and 2a should be classified as low grade and tumours defined as grade 2b should be classified as intermediate grade.

Urothelial atypia concomitant with primary bladder tumour. Incidence in a consecutive series of 500 unselected patients

A consecutive series of 500 primary bladder tumours from a single clinic is presented, with distribution of the tumours according to T category and histologic type and grade. Mucosal biopsies were obtained from pre-selected sites at initial cystoscopy or initial transurethral resection of the tumour in 396 cases. In 54% of the patients with grade III tumour there was concomitant urothelial atypia, either carcinoma in situ (urothelial atypia grade III, 30%) or urothelial atypia grade II (24%). In 30% of the patients with invasive grade II bladder tumour and in 14% of those with noninvasive grade II tumour there was concomitant urothelial atypia, mostly grade II. Since concomitant urothelial atypia predicts new tumour growth after successful transurethral surgery or radiotherapy, mucosal biopsies should be performed at preselected sites during initial cystoscopy or transurethral tumour resection in order to identify high-risk patients.

Assessment of radiotherapy in invasive bladder carcinoma using in vivo methylene blue staining technique

In vivo methylene blue staining of the bladder urothelium is a useful method as an adjunct to cystoscopy in detection of recurrent tumors or new ones after radical radiotherapy. The depth of staining correlates well with the grade of bladder tumor differentiation. It is a simple, safe, and acceptable procedure.

The significance of urothelial dysplasia as diagnosed by cup biopsies

A prospective study was carried out in which four quadrant cold cup biopsies of the bladder were taken from patients with either a bladder tumour (57) or irritative bladder symptoms (44), and a control group (23). Five histopathological patterns were recognized: normal urothelium, mild, moderate and severe dysplasia, and carcinoma in situ (CIS). In the control group, 22 of the 23 patients had normal urothelium, giving a 4% incidence of mild dysplasia. Of the 57 patients with all stages and grades of transitional cell carcinoma, 38 (67%) had dysplastic urothelium. This association is significant (P less than 0.01, chi-squared). Thirty-seven patients had Ta or T1 tumours, and 24 (65%) of these had dysplasia, including four (11%) with CIS. Twenty patients had T2-T4, Grade 111 tumours and 14 (70%) of these had dysplasia, including five (25%) with CIS. There was no statistical difference between these two groups. The recurrence rate was evaluated for all patients presenting with a first bladder tumour. Seventy-three percent of patients with normal cup biopsies remained recurrence free during a mean follow-up of 3 years (s.d. 1.15 years). Of patients with dysplastic urothelium, 72% remained recurrence free over a mean follow-up of 3.25 years (s.d. 1.23 years). Hence, the presence of dysplasia did not predict the likelihood of tumour recurrence. Thirty patients had dysuria or suprapubic pain for which there was no explanation. Sixteen (53%) had dysplasia on cup biopsy including three (10%) with CIS (P less than 0.01, chi-squared). It seems clear, therefore, that the dysplasia was the cause of these symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Significance of carcinoma in situ and dysplasia in association with bladder cancer

Cystectomy specimens of 118 transitional cell carcinomas of the bladder were analyzed by step-sectioning. The carcinoma in situ and dysplasia adjacent to and remote from the visible bladder cancer were correlated with the tumor configuration on cystoscopy, and grade and stage of the disease. Results showed that a combination of papillary and nodular carcinomas in a single bladder was associated with a high incidence of mucosal involvement. Moreover, more than 50 per cent of all grade 3 carcinomas were associated with carcinoma in situ and dysplasia adjacent to and remote from the visible tumors. Carcinoma in situ and dysplasia were not related to the stage of disease. For management of bladder cancer, it appears important to assess the gross configuration of tumors by cystophotography and to determine the grade of tumors by biopsy, because mucosal involvement was found to be correlated closely with the tumor configuration and grade 3 disease.

Relation between flow cytometric DNA distribution and pathology in human bladder cancer. A report on 69 cases

High-resolution flow cytometric measurements of cellular DNA content have been performed in 69 patients with transitional cell carcinomas of the urinary bladder. By selective sampling of cells at cystoscopy, mapping of the whole bladder could easily be performed, including the tumor as well as different areas of the surrounding normal-appearing mucosa. The cell-cycle distribution showed an increasing fraction of cells with S- and G2-phase content parallel to the World Health Organization (WHO) grade of the tumors, ranging from 1.7% S-phase cells in normal subjects to nearly 20% in tumors of WHO grade 3. WHO grade 2 tumors could be divided into two populations: (1) diploid, with a cell-cycle distribution similar to grade 1 tumors and low frequency of infiltration; and (2) aneuploid, with a high rate of infiltration and high fractions of S- and G2-phase cells. Furthermore, the aneuploid tumors could be subdivided into two main classes, one hypertriploid with high frequency of involvement of the surrounding normal appearing mucosa; and one hypotetraploid, with less frequency of such involvement and infiltration. It is concluded that by selective sampling and mapping of the bladder mucosa using flow cytometry, subclassification of this type of tumor can be performed rapidly, giving a reliable measure of the involvement of the bladder in the neoplastic disease and a biologic subclassification based on the type of DNA aberrations.

Intravesical adriamycin therapy in carcinoma in situ of the urinary bladder

Intravesical Adriamycin treatment was given to 22 patients with carcinoma in situ of the urinary bladder. The treatment schedule consisted of monthly Adriamycin instillations in a dose related to bladder capacity. Endoscopic inspection with multiple bladder biopsies and cytoanalysis of urine was performed after every third instillation. In two patients there was lasting disappearance of the carcinoma in situ. Another 10 patients possibly had a beneficial effect of the treatment. The remaining 10 patients showed persistent malignancy and in 6 of these, progression of carcinoma in situ during Adriamycin treatment necessitated cystectomy or radiotherapy. The histologic and cytologic findings showed distinct variability in most patients, with atypia or even absence of malignant cells often followed by recurrence. Adriamycin was discontinued in four cases because of severe cystitis, and in one case because of an anaphylactoid reaction following instillation of the drug.

Ploidy disturbance of normal-appearing bladder mucosa in patients with urothelial cancer: relationship to morphology

A total of 4 patients with transitional cell carcinoma of the bladder underwent complete mapping of the mucosa and tumors with combined cytologic, histologic and flow cytometric evaluation of the extent of involvement of the neoplastic process. Flow cytometric measurement of the cellular deoxyribonucleic acid content in multiple cell samples taken at cystoscopy showed similar changes in the normal mucosa as in the tumors. These changes consisted of an increased fraction of cells with S-phase deoxyribonucleic acid content in 2 patients with grades 1 and 2 tumors, and the presence of extensive aneuploidy in 2 patients with World Health Organization grades 2 and 3 tumors. While grade 1 and some grade 2 tumors (World Health Organization) are composed only of diploid cells, some of the grade 2 and all grade 3 tumors consist of a mixture of diploid and aneuploid populations. Such aneuploid clones could be identified in normal-appearing mucosa and, thus, be a source of new occurrences. The impression of heterogeneity in histograms from different tumors within the same bladder is assumed to be caused by a variation in the ratio between aneuploid and diploid populations (high ratio in tumor and low in normal-appearing mucosa). This phenomenon may be the reason for variation in grading based on histological studies.

Carcinoma in situ of the urinary bladder with and without associated vesical neoplasms

Of 99 patients who had carcinoma-in situ (TIS) at least once between 1970 and 1980, 84 were subjected to detailed analysis and pathologic review. They may be classified into four groups: (Group 1) 14 patients, who presented with invasive bladder carcinoma (TCC) associated with TIS; (Group 2) 15 patients who, subsequent to the diagnosis of TIS with or without another superficial TCC developed muscle invasion (12 patients) or metastases without muscle invasion (three patients); (Group 3) 29 patients who underwent cystectomy for superficial TCC (Ta or T1, or TIS alone). Twenty (69%) had extravesical superficial extension. Two patients developed metastases subsequent to undergoing cystectomy; and (Group 4) 26 patients with TIS proven at least once who have not developed muscle invasion, metastases nor have undergone cystectomy. Nineteen had previous non-TIS superficial TCC. All patients in Groups 2 and 4 were treated conservatively (TUR +/- intravesical chemotherapy) when the initial diagnosis of TIS was made. Twelve patients in Group 3 underwent cystectomy within a month of the diagnosis of TIS. When 38 patients found to have TIS in association with the first diagnosis of superficial transitional cell carcinoma of the bladder were compared with 32 patients who had TIS diagnosed subsequent to their initial diagnosis of transitional cell carcinoma, the former group fared significantly worse (P less than 0.01) in regard to muscle invasion, metastases, or clinical indications for cystectomy.

Urothelial dysplasia concomitant with bladder tumours as a determinant factor for future new occurrences

Of 53 patients with primary bladder tumours of categories T1 or T2 about 50% had concomitant urothelial dysplasia, either carcinoma-insitu or less dedifferentiated dysplasia graded as grade II. In a follow-up study of these patients treated with transurethral resection alone, it was found that new occurrences had developed in 87% of patients with concomitant urothelial dysplasia, compared with 26% of those without dysplasia. Most new occurrences developed within 6 months of initial tumour resection. A new invasive tumour developed in all patients with concomitant carcinoma-in-situ, emphasising the serious prognostic significance of that entity. Thus, urothelial dysplasia concomitant with a bladder tumour is an important determinant factor for future new occurrences.

The association of urothelial abnormalities with neoplasia: a 10-year followup

More than 10 years ago we reported on the histological appearance and clinical significance of random biopsies of the intervening urothelium in 100 patients with transitional cell carcinoma of the bladder. Although the biopsied mucosa appeared normal cystoscopically a surprisingly large number of abnormalities were found: only 5 per cent of the patients had normal urothelium, 40 per cent had established carcinoma in situ and the remaining 55 per cent had changes described variously as cystitis glandularis, atypia and metaplasia. In the intervening decade these patients have been followed carefully and have been reviewed to determine their fate. Of the original 100 cases 92 were sufficiently well documented to make a meaningful analysis. The outstanding finding was that patients with carcinoma in situ had a significantly worse outcome statistically than those with normal mucosa or nonmalignant aberrations regardless of the characteristics of the primary tumor and its grade or stage (p less than 0.001). A detailed analysis is presented in relation to the clinical and experimental findings, suggesting that patients with carcinoma in situ associated with the primary tumor may require treatment to supplement the initial tumor resection.

Prognostic factors in local surgical treatment of invasive bladder cancer, with special reference to the presence of urothelial dysplasia

Thirty-three patients with bladder cancer of categories pT1 or pT2 were treated by transurethral resection alone. At the initial diagnosis random preselected site mucosal biopsies were obtained to demonstrate the presence or absence of concomitant urothelial dysplasia. A statistically significant (P less than 0.01) relationship was found between the presence or absence of concomitant urothelial dysplasia and the development of new occurrence or the absence of recurrence at cystoscopic follow-up. Four of six patients with concomitant carcinoma in situ developed invasive bladder cancer within 6 months demonstrating the serious prognostic significance of this entity. Thus, the presence or absence of concomitant urothelial dysplasia at the initial diagnosis of invasive bladder cancer seems to be an important prognostic factor for future new occurrences.

Mapping of cell cycle distribution in normal human urinary bladder epithelium

A method is described by which urothelial cells from well defined areas in the urinary bladder mucosa can be obtained. At cystoscopy epithelial cells are aspirated by means of a ureteral catheter. The cells obtained by this selective sampling technique are well suited for morphology and for quantitative single cell measurements by flow cytometry (FCM). In the present study the cell cycle distribution has been measured by FCM. Twenty-five patients (13 males and 12 females) had urothelial cells collected from well defined areas in the mucosa and the DNA content measured from different sites separately. The distribution of bladder mucosa cells in the different parts of the cell cycle (G1, S-phase and G2 + M) is reported. No significant differences were found with regard to sex and age of the patients. Also, a low regional variation was found in the bladder mucosa indicating that the method should enable the discrimination of even small abnormal cell populations in tumour disease. No evidence of polyploidy in the human urothelium was found.

TNM (1978) in bladder cancer: use and abuse

Modifications to the TNM classification for bladder cancer, introduced in 1979, are described. The use of this classification was evaluated in 106 new patients. It proved to be satisfactory for in situ and papillary tumours but major problems occurred in attempting to separate superficially invasive from deeply invasive tumours. Several aspects of this classification require further consideration and modifications are proposed.