Multivariate analysis of flow cytometric deoxyribonucleic acid parameters and histological features for prognosis of bladder cancer patients

Recent Aspects in the Diagnosis and Prognosis of Bladder Cancer

Epidemiologic studies have stated the progressive increase of bladder tumors during the last decades. The aim of our review is to refer to factors implicated in bladder carcinogenesis (such as activated oncogenes, growth factors and chromosomal aberrations) and to resistance to drug uptake (i.e., multidrug resistance gene and P-glycoprotein). The review also provides information of diagnostic and prognostic significance, based on DNA analysis of transitional cancer cells. In addition to cytometric data, alternative counterings for estimation of the S-phase fraction, useful in indicating the biologic behavior of bladder cancer, are presented. Knowledge of such mechanisms results in a better approach to the diagnosis, prognosis and prevention of bladder carcinomas, especially those that do not respond to systemic intravesical chemotherapy. We have tried to mention all significant factors related to the development of bladder cancer. We conclude that the progress made in understanding the pathogenesis of bladder cancer has been significant. However, more studies are needed in order to introduce and adopt reliable criteria to accurately predict the clinical behavior.

[Bladder carcinoma cell lines as models of the pathobiology of bladder cancer. Review of the literature and establishment of a new progression series]

BACKGROUND

Tumour cell lines represent valuable preclinical models to decipher underlying biology and identify potential therapy targets and pharmacologically useful compounds. Approximately 50 human bladder cancer cell lines have been established to date, mainly from invasive and metastatic tumours. Two of these, namely T24 and 253J, were experimentally further developed into progression series. These models have provided important insights into later tumour progression events and metastatic dissemination. Only a few cell lines are available as models of non-invasive papillary bladder cancer and no progression series have yet been established.

MATERIAL AND METHODS

During the course of establishing a doxorubicin-resistant variant cell line of the human papillary bladder carcinoma cell line BFTC-905, a unique cell colony was identified, apparently involving cells with divergent growth patterns. Subsequent subculturing yielded three daughter cell lines, BFTC-905-compact, BFTC-905-diffuse und BFTC-905-diffuse M. Their fundamental characterization included basic cell morphology, cell membrane expression of E-Cadherin, karyotype analysis, invasion and colony forming capacity in soft agar. The clonal origin of the newly established daughter cell lines was assessed by means of molecular genetic methods.

RESULTS

We could identify important differences in multiple transformation related traits among the cell lines of the BFTC-905 progression series. Both diffuse cell lines (BFTC-905-diffuse und BFTC-905-diffuse M) differed from the BFTC-905-compact cell line by growing in a less organized,"diffuse" manner, which involved colonies of cells exhibiting apparently normal cell-to-cell adhesion as well as individual cells outside of them. This diminution of the cell-to-cell adhesion was accompanied by a corresponding decrease of membranous E-Cadherin. The BFTC-905-diffuse M cell line displayed a dramatic increase in the overall chromosome number, resulting in a hypertetraploid karyotype. At the same time, this cell line, as the only one in the progression series, acquired the ability to grow independent of anchorage in soft agar. All three cell lines remained noninvasive. Allelic distribution of highly polymorphic DNA-markers in the cell lines of the BFTC-905 progression series provided unequivocal evidence of their common origin.

CONCLUSION

The newly established BFTC-905 progression series manifests two aspects of the early progression of non-invasive bladder carcinoma, not exhibited by any other progression series published so far, namely dynamic changes in the expression of E-Cadherin and a complex karyotypic evolution. It may thus contribute important insights into further understanding of the pathobiology of bladder cancer.

[Flow cytometric DNA analysis and cytology in diagnosis and prognosis of bladder tumors: preliminary results of a comparative study of bladder lavage]

OBJECTIVE

To compare flow cytometric data (ploidy and proliferative activity or percentage SG2M-phase cells) to cytologic and histologic data of the bladder carcinomas.

MATERIALS AND METHODS

Cytologic and flow cytometric analysis of DNA content were performed on 48 bladder washings: 28 bladder washings from patients being followed for urothelial carcinomas and 20 control washings from individuals undergoing cytoscopy for other reasons.

RESULTS

Cytological sensitivity and specificity of bladder washing were 75% and 91% respectively. Specificity was increased to 94% using flow cytometric DNA analysis whereas sensibility was moderately decreased to 68%. Combination of flow cytometry and cytology increased the diagnostic yield to 100%. The study of the patient group showed an increased abnormalities (aneuploidy and/or proliferate activity SG2M > 10%) according to the tumor grading and tumor staging. A cytometric test was positive in 80% for G3 tumours and in 68% for G2 tumours. The staging tumor was positive in 46%, 89% and 100% of the pTa-pT1, pT2 and pT4 tumours respectively. Otherwise the comparison of control group with patients showed a statistical correlation between cytometric test, staging tumour and tumoral grading as showed in the following groups: control/G1-G2 (p < 0.05), control/G3 (p < 0.001), control/pTa-pT (p < 0.05), control/pT2-pT4 (p < 0.001).

CONCLUSION

We confirmed through this study the interest of the flow cytometric DNA analysis in the diagnosis and prognosis of bladder carcinomas, and we showed the importance of the histogram classification in order to facilitate their interpretation and to avoid the trap of false aneuploidy.

[DNA ploidy determination with flow cytometry, Ki-67 index and overexpression of p53 protein in 121 T1 superficial bladder carcinomas. Retrospective studies. Part II: Prognostic value and usefulness in the indication for prophylactic treatment with BCG]

OBJECTIVE

Evaluate the utility of Ki-67 label index, p53 expression and flow cytometry-DNA ploidy in the selection of groups to be treated with prophylactic BCG and the prognostic value compared with the classic variables (grade, lymphatic permeation, multiplicity, volume, primary).

MATERIAL & METHOD

121 superficial bladder tumors T1. 10% Cut-off level for Ki-67 and p53. Aneuplody is defined as a tumor with DNA index different of 1 or more than 20% in G2-M phase. 71 (58.7%) received BCG.

RESULTS

In uni and multivariate analysis positivity to Ki-67 is correlated with recurrence. Progression is correlated with lymphatic permeation (p .0003), volume (p .016), ploidy (p .022) and positivity to p53 (p .007). In multivariate analysis, volume and positivity to p53 are independent variables. None were of utility to prevent recurrence, but Ki-67 positive or aneuploid treated tumors had less progression (p .025 and p .009 respectively). The p53 negative treated tumors had less progression too.

CONCLUSIONS

Only Ki-67 is correlated with tumoral recurrence. P53 and tumor volume are correlated with stage progression. If the results are confirmed with bigger series, the Ki-67 positive and/or aneuploid tumors would obtain benefits of prophylactic treatment with BCG.

Identification by quantitative chromatin pattern analysis of patients at risk for recurrence of superficial transitional bladder carcinoma

PURPOSE

Based on the actual clinical outcomes of 132 fully documented patients with superficial transitional cell carcinoma of the bladder, we characterize the risk of recurrence and/or progression by computer assisted image microscopy applied to Feulgen stained nuclei.

MATERIALS AND METHODS

Each tumor was characterized by the conventional grading and staging systems as well as by cytometry generated variables describing nuclear DNA content, nuclear morphometry and chromatin patterns. These data were submitted to discriminant analysis to establish a model distinguishing between 2 groups of patients. Group 1 included cases with remission for more than 60 months and group 2 cases presented with recurrence with or without progression within 12 months of transurethral bladder resection. This latter model was then validated by Kaplan-Meyer analysis of the full data set.

RESULTS

As evidenced by Kaplan-Meier analysis, the discriminant factor generated by discriminant analysis of cytometry generated variables provided a cutoff value for distinguishing between low and high risks of recurrence (p <0.00001). In contrast, conventional grading and staging systems were not able to make such efficient distinction.

CONCLUSIONS

These 2 groups can be used as references with which new cases can be compared to prognosticate disease behavior independently of histopathological grading and/or clinical staging.

DNA ploidy and p53 protein expression in superficial transitional cell carcinoma of the bladder

Superficial transitional cell carcinoma of the bladder (STCCB) is a heterogeneous group of neoplasias with an unpredictable clinical course. In recent years many techniques have been used in order to predict the behaviour of these tumours at individual patient level. The aim of this study was to investigate in imprints from tumour biopsies the DNA ploidy and p53 protein expression in a group of 80 STCCB (pTa-pT1) patients in relation to histological grade and recurrence status. The DNA content was studied in Feulgen-stained imprints by the image analysis technique using a SAMBA 2005 analyser. In order to investigate p53 protein expression an avidin-extravidin immunocytochemical technique was used. According to our measurements a strong correlation was observed between recurrence status and DNA ploidy status (P < 0.001). No statistical difference was found in DNA ploidy status and grade of malignancy (P = 0.68). A statistically significant difference was found in p53 protein expression between recurrent and nonrecurrent tumours (P < 0.001). No statistically significant difference was found among tumours of grade I, grade II and grade III (P = 0.42). These results could provide useful information on the potential behaviour of STCCB.

Prognostic significance of flow cytometric deoxyribonucleic acid analysis for patients with superficial bladder cancers: a long-term follow-up study

Flow cytometric DNA ploidy analysis for human bladder cancers may provide significant diagnostic and prognostic potential. We have previously reported that combined use of histologic and flow cytometric parameters may offer additional information regarding the clinical outcome for bladder cancer patients. However, the evaluation included both superficial and muscle-invasive tumors. In the present manuscript, we present our study on whether flow cytometric determination yields significant prognosticators beyond the classical histologic evaluation only in the patient with superficial bladder cancer. A total of 217 patients with untreated bladder cancer were evaluated, using fresh bladder tumor specimens. Tumor grading (grade 1, 2, and 3) and stage (pTa + pT1a and pT1b) served as the histologic prognostic parameters. Multiple flow cytometric parameters assessed included DNA index, percentage S-phase cells, percentage G2/M-phase cells, and hypertetraploid cell presence. Multivariate survival analysis was performed using the SAS proportional hazard regression procedure to study statistical individual prognostic values of both the histologic and the flow cytometric parameters. Clinical follow-up of more than 60 months was required, with the mean follow-up being 116.3 +/- 18.6 months. Hypertetraploid cell presence was the single most important prognostic factor (p < 0.01; risk ratio: 14.3), with the second being tumor grade (p < 0.05; risk ratio: 4.6). No other parameters, including tumor stage, the DNA index, and cell phase fractions, contributed to the model. These results indicate that hypertetraploid cell presence found by flow cytometric determination may provide additional information regarding the clinical outcome for superficial bladder cancer patients, and can be used as an indicator for decision making in treatment of superficial bladder cancer patients.

Predictive value of DNA ploidy in bladder cancer treated with preoperative radiation therapy and cystectomy

The predictive value of flow cytometric DNA analysis of cells from bladder washings was evaluated in 43 patients with muscle-invasive or recurrent superficial bladder cancer treated with preoperative radiotherapy and cystectomy. There was no correlation between ploidy status of the primary tumour and survival, neither was there any correlation between ploidy and the occurrence of residual tumour in the cystectomy specimens. Patients without residual tumours in the cystectomy specimen had significantly longer survival time than those with residual tumours. Concomitant carcinoma in situ was correlated with better survival, which is surprising, considering the malignant potential of this lesion. In this study DNA ploidy did not predict tumour response to radiotherapy nor was it of any prognostic significance.

The use of the decision tree technique and image cytometry to characterize aggressiveness in World Health Organization (WHO) grade II superficial transitional cell carcinomas of the bladder

The aggressiveness of human bladder tumours can be assessed by means of various classification systems, including the one proposed by the World Health Organization (WHO). According to the WHO classification, three levels of malignancy are identified as grades I (low), II (intermediate), and III (high). This classification system operates satisfactorily for two of the three grades in forecasting clinical progression, most grade I tumours being associated with good prognoses and most grade III with bad. In contrast, the grade II group is very heterogeneous in terms of their clinical behaviour. The present study used two computer-assisted methods to investigate whether it is possible to sub-classify grade II tumours: computer-assisted microscope analysis (image cytometry) of Feulgen-stained nuclei and the Decision Tree Technique. This latter technique belongs to the Supervised Learning Algorithm and enables an objective assessment to be made of the diagnostic value associated with a given parameter. The combined use of these two methods in a series of 292 superficial transitional cell carcinomas shows that it is possible to identify one subgroup of grade II tumours which behave clinically like grade I tumours and a second subgroup which behaves clinically like grade III tumours. Of the nine ploidy-related parameters computed by means of image cytometry [the DNA index (DI), DNA histogram type (DHT), and the percentages of diploid, hyperdiploid, triploid, hypertriploid, tetraploid, hypertetraploid, and polyploid cell nuclei], it was the percentage of hyperdiploid and hypertetraploid cell nuclei which enabled identification, rather than conventional parameters such as the DI or the DHT.

Il valore predittivo della citometria a flusso nei carcinomi superficiall della vescica di basso grado

Flow cytometry (FCM) enables ploidy and proliferative tissue activity (PHASE S) to be quickly and objectively measured. This method is of predictive value regarding the biological behaviour of bladder tumours. The authors used FCM in a 5-year-follow-up study of 75 patients with papillary bladder carcinoma, who underwent therapeutic or staging transurethral resection in 1989. Results show a strict correlation between stage-ploidy-Progression as well as the significance of S-PHASE cells in relation to low-grade diploid tumours.

Possibile ruolo della citofluorometria (CFM) nel monitoraggio della risposta alla terapia endocavitaria con BCG nel carcinoma in situ della vescica: Monitoring the response to intravesical BCG in the treatment of cis: A possible role of flow cytometry

We report our experience on the treatment of carcinoma in situ (CIS) using intravesical therapy with the Bacillus Calmette-Guerin (BCG). From November 1992 to September 1994, 18 patients received treatment: 6 had associated CIS and 12 secondary CIS. Ploidy of each tumour was determined by flow cytometry. Aneuploidy was found in 12 cases, diploidy in 6 cases. After treatment, a standard bladder mapping was performed: 14 patients showed no evidence of cystoscopic and histological disease and if previously aneuploid, became diploid. 4 patients has recurrent disease after therapy; they were all aneuploid before treatment. One of these showed a persistent aneuploidy, although both voided urinary cytology and histological samples were negative. Six months later, a recurrent CIS was seen at the time of cystoscopy. These results enhance the interest in flow cytometry as a possible predictor of response to BCG in the treatment of CIS.

Indici di proliferazione (Ki 67, TLI) ed espressione della p53. Introduzione: Proliferation indices (Ki 67, TLI) and p53 expression. Introduction

Histologic and pathologic findings are the most common and useful prognostic factors in transitional cell cancer of the bladder. Thus, clinicians know their peculiar limits very well. The Authors report the results of a literature review about an oncogenic-derivative protein (p53) and about indices of proliferation Ki 67 and TLI, which are frequently studied in bladder cancer.

Indici di proliferazione (Ki 67, TLI) ed espressione della p53. Esperienza personale: Proliferation indices (Ki 67, TLI) and p53 expression. Personal experience

The Authors report their experience on the study of urothelial bladder cancer by determining the overexpression of p53, DNA-content by flow-cytometry, Ki 67, TLI and cytofluorimetric S-phase in 81 patients. Ki 67, DNA content and p53 overexpression are statistically related with histologic grade, unlike TLI and S-phase. TLI, overexpression of p53 and Ki 67 are statistically related with stage, whereas ploidy and S-phase do not show any relation with stage. The Authors discuss these findings.

L'analisi del DNA mediante citometria a flusso nei tumori superficiali della vescica: DNA analysis through flow cytometry in superficial bladder tumours

The aim of this work is to try to characterize the prognostic value of DNA flow cytometry in superficial bladder tumours and to try to indicate this investigation in clinical practice. The Authors review results reported in literature and those relative to their experience. Data investigation shows that this test has prognostic significance because it is correlated with the stage and grade of the tumour. The correlation with the clinical development of the tumour is not clear in the Authors’ experience. The Authors think that flow cytometry does not have a precise role in clinical practice.

The use of digital image analysis of chromatin texture in Feulgen-stained nuclei to predict recurrence of low grade superficial transitional cell carcinoma of the bladder

BACKGROUND

Identifying a marker enabling prediction of recurrence in the group of superficial transitional cell carcinomas (sTCCs) of the bladder remains an important challenge today. This report quantitatively describes chromatin patterns with respect to such sTCC recurrence.

MATERIALS AND METHODS

Twenty-nine patients with sTCCs who did not exhibit tumor recurrence within a minimum of 24 months were compared with 21 patients with sTCCs who exhibited tumor recurrence two or three times in a 24-month period, for a total of 74 sTCCs. Quantitative chromatin pattern description was performed by the digital cell image analyses of Feulgen-stained nuclei. Six morphonuclear parameters were thus described and subsequently used to determine a score, allowing biological behavior of sTCCs to be described, i.e., recurrence versus non-recurrence in one calculation step. DNA ploidy level was also determined in each sTCC by assessing its DNA histogram type.

RESULTS

Of 32 patients with Grade 1 pathologically classified pTa/pT1 tumors, DNA ploidy level determination permitted correct prediction of tumor nonrecurrence or recurrence of 13 (41%), whereas determination of the score values enabled prediction of nonrecurrence or recurrence of 25 (78%). Combining DNA ploidy level data and the score values enabled recurrence or nonrecurrence to be predicted for 29/32 of the patients (91%).

CONCLUSIONS

The quantitative description of chromatin patterns by digital cell image analysis of Feulgen-stained nuclei can provide helpful information, in addition to DNA ploidy level determination, in predicting tumor recurrence of low grade superficial transitional cell carcinomas of the bladder.

Image cytometry determination of ploidy level, proliferative activity, and nuclear size in a series of 314 transitional bladder cell carcinomas

Image cytometry was carried out on 281 superficial (Ta and T1) and 33 invasive (T2 to T4) bladder cancers. The parameters used to characterize these bladder tumors were: (1) histopathological grading, (2) clinical staging, (3) tumor size, (4) deoxyribonucleic acid (DNA) index (DI), (5) DNA histogram type (DHT), (6) percentage of euploid (diploid plus tetraploid) cells, (7) percentage of polyploid cells (> 5C DNA content), (8) proliferative activity (S phase fraction value), and (9) nuclear area (NA). The proliferative activity of the tumors was not related to either histopathological grade or to clinical stage, but it was related to the DHT parameter, which made it possible to identify diploid, hyperdiploid, triploid, hypertriploid, tetraploid, and polymorphic tumors. The hypertriploid tumors exhibited a significantly lower proliferative activity than the nonhypertriploid ones. Although both the DI and the NA values correlated significantly with histopathological grading, only the NA values correlated significantly with clinical staging. We further observed that some grade III bladder tumors were definitely diploid, whereas some grade I tumors were highly aneuploid. We thus hypothesize that the ploidy level of a given tumor reflects its age directly and its aggressiveness only very indirectly. In our opinion aneuploidy is only an indirect marker of aggressiveness because it reflects the fact that a malignant tumor is old, ie, has been present in a patient over a long period of time and has had ample time to express its malignancy at the clinical level. A significant relationship was accordingly obtained between tumor size and ploidy level with the highest proportion of aneuploid tumors and the highest percentage of polyploid cell nuclei being observed among the largest bladder tumors.

Prognostic significance of selected lifestyle factors in urinary bladder cancer

To examine the prognostic significance of lifestyle factors in urinary bladder cancer, we conducted a follow-up study of 258 incident bladder cancer patients, who were originally recruited in a case-control study in metropolitan Nagoya. Information on individual survivals was obtained from the computer data-file of the tumor registry of the Nagoya Bladder Cancer Research Group. Univariate analyses revealed significant associations of 5-year survivorship with educational attainment, marital status, drinking habits and consumption of green tea in males, and age at first consultation, histological type and grade of tumor, stage and distant metastasis in both sexes. After adjustment for age, stage, histology (histological type and grade) and distant metastasis by means of a proportional hazards model, drinking of alcoholic beverages was significantly associated with the prognosis of bladder cancer in males. Its adjusted hazard ratio was 0.46 (95% confidence interval: 0.26-0.79), favoring patients who had taken alcoholic beverages. In detailed analysis, ex-drinkers and all levels of current drinkers demonstrated hazard ratios smaller than unity, although no clear dose-response relationship was detected. No prognostic significance was found for such lifestyle factors as smoking habit, uses of artificial sweeteners and hairdye, and consumption of coffee, black tea, matcha (powdered green tea) and cola.

Significance of abnormal diploid DNA histograms in localized prostate cancer and adjacent benign prostatic tissue

To clarify the relationship of DNA ploidy to tumor grade and volume, 32 clinical Stage B prostate cancers, with low and high Gleason scores and small and large tumor volumes, were compared with adjacent histologically normal prostate tissue and with samples from benign prostatic hyperplasia (BPH). All 22 samples from benign glands were diploid, with 2.7 +/- 1.2% tetraploid (4C) cells. Samples from cancer-bearing glands were considered diploid (normoploid) if they had a major diploid (2C) peak and a small 4C peak with the percentage of cells falling within 3 standard deviations of the figure found for BPH. Abnormal ploidy included abnormal diploid (6.3-14.9% 4C), tetraploid (> or = 15% 4C), and aneuploid samples (peaks not at 2C or 4C). Abnormal DNA ploidy was found to be related to tumor volume. All five tumors smaller than 0.4 cm3 and their adjacent benign tissue were normoploid; however, 10 of 13 cancers with volumes of 0.4-1 cm3 had abnormal ploidy (9 abnormal diploid, 1 tetraploid) and 6 of 9 of the adjacent benign tissue samples also were abnormal diploid. All larger tumors (> 1 cm3) showed abnormal ploidy (7 abnormal diploid, 3 tetraploid, 5 aneuploid). For large tumors, abnormal ploidy was present in 10 of 13 of the adjacent benign areas (8 abnormal diploid, 2 benign areas that were clearly aneuploid). Abnormal diploid cancers are intermediate forms between diploid and tetraploid tumors, as defined above. Although they have fewer 4C cells than tetraploid cancers, they have equivalent numbers of hypertetraploid cells (BPH: 1.3 +/- 0.9%; abnormal diploid: 10.8 +/- 5.4%; tetraploid: 11.1 +/- 6.8% hypertetraploid cells). Thus, the authors propose that abnormal diploid cancers represent an early stage in ploidy progression. DNA ploidy abnormalities also occur in benign prostatic tissue adjacent to many prostate cancers, consistent with the concept that human prostatic cancer is a field-change disease.

Flow Cytometry in Bladder Tumours: Our Experience

From January 1992 to January 1993, specimens from bladder tumours of 75 patients were analyzed by cytometry (FCM). Our data show a good correlation between tumour stage and grade, and tumour ploidy. Furthermore, aneuploid tumours showed progression more often than diploid tumours. A larger number of patients admitted to the study and a more prolonged period of follow-up will be necessary to confirm our initial data and to investigate whether a correlation exists between FCM and tumour progression and patient survival.

Prognostic Value of Flow Cytometry in Bladder Tumours

During this last decade, flow cytometry (FCM) has been widely investigated and employed in assessing the DNA content of bladder tumours. The prognostic value of FCM is recognised by the majority of investigators, above all when it concerns superficial transitional cell carcinoma of the bladder. The determination of ploidy and the degree of aneuploidy seem to offer valuable prognostic information. The Authors have reviewed Literature on this subject, identifying three different categories of studies that analyse the relation of FCM to cytohystological characterisation, to the clinical behaviour of the tumours and to the patients’ survival.

Prognostic significance of bromodeoxyuridine high labeled bladder cancer measured by flow cytometry: does flow cytometric determination predict the prognosis of patients with transitional cell carcinoma of the bladder

We studied whether flow cytometric determination of proliferative cell activity estimated by the bromodeoxyuridine in vitro labeling technique provides significant prognosticators beyond the classical histological evaluation in the patient with bladder cancer. We evaluated 81 patients with transitional cell carcinoma of the bladder using fresh bladder specimens. Clinical followup of at least more than 24 months was requested, with the mean followup being 37.9 +/- 10.5 months. Tumor grade and stage were the histological prognostic parameters. Flow cytometric bivariate measurements of deoxyribonucleic acid (DNA) ploidy and bromodeoxyuridine labeled cell index were evaluated. Tumors with a bromodeoxyuridine labeled cell index of more than 10.7%, which was the value of the mean plus 2 times the standard deviation obtained in grade 1 bladder tumors, were designated as high bromodeoxyuridine labeled cell index tumors. A total of 51 patients with low bromodeoxyuridine labeled cell index tumors demonstrated a 98.0% 3-year actuarial survival rate estimated by the Kaplan-Meier method, compared to 42.9% for those with high index tumors. Multivariate survival analysis was performed with Cox's proportional regression model to study statistical individual prognostic values of histological and flow cytometric parameters. Histological tumor grade was the single most important prognostic factor (risk ratio 13.2, p < 0.05), with tumor stage being the second most important (risk ratio 9.2, p < 0.05), followed by bromodeoxyuridine labeled cell index status (risk ratio 6.9, p < 0.05). DNA ploidy status did not influence the clinical outcome. When grade 3 tumors were classified as low and/or high bromodeoxyuridine labeled cell index tumors, 3-year actuarial survival rates were 85.7% and 27.3%, respectively. These results indicate that DNA/bromodeoxyuridine bivariate analysis can be used as an effective adjunct to histological examination for prognostication and decision-making in treatment of bladder cancer patients.

Flow cytometry in comparison with mitotic index in predicting disease outcome in transitional-cell bladder cancer

The DNA content and S-phase fraction were measured by flow cytometry in 448 tumour biopsy specimens from transitional-cell bladder cancer (TCC). The samples were also analyzed for mitotic index, WHO grade and papillary status, and histological and flow cytometric data were then correlated to clinical behaviour of tumours during a mean follow-up period of 9.9 years. TNM classification, WHO grade, papillary status, mitotic index, DNA ploidy and S phase fraction were significantly interrelated. Twenty-four percent of tumours showed heterogeneous DNA indices when measured from multiple samples (measured in 94 cases). Of the histological parameters, independent predictors of progression in superficial tumours were the S-phase fraction and mitotic index. In superficial tumours, S-phase fraction and the mitotic index included all the available independent prognostic information in survival analysis, whereas in muscle-invasive tumours T category was the most important prognostic factor. The results suggest that DNA ploidy has no independent prognostic value in transitional-cell bladder cancer, whereas proliferation indices (SPF, mitotic index) are important prognostic factors. Accordingly, malignancy classification of papillary bladder tumours can be based on proliferation indices alone. Nodular tumours run an unfavourable course and their malignancy grading by flow cytometry or by mitotic index is not relevant.

Evaluation of DNA flow cytometry as a screening test for bladder cancer

At this present time, we feel that there is no role for DNA flow cytometry (FCM), or indeed DNA studies by any other method, to be used as a screening procedure for patients with no prior history of bladder cancer due to the high false-positive rate found when monitoring exfoliated urothelial cells. On the other hand, for patients who have had a superficial transitional cell carcinoma (TCC), which has a documented 50% recurrence rate, and depending on pathological features, a progression rate from 7 to 45%, DNA FCM provides a sensitive method to predict future disease recurrence. It provides an extremely effective way to predict future progression and further acts as a method to monitor changes in the malignant potential of the patient's disease. For those patients with a past history of superficial TCC who develop abnormal ploidy without any overt tumor, 80% will, within the next four years, suffer a disease recurrence. For the patient who has a Ta TCC and receives intravesical Bacillus Calmette-Guerin (BCG), the development of abnormal ploidy in bladder washing specimens is the single best indicator for future disease recurrence. Similarly, a negative DNA FCM of a bladder washing at six months after intravesical therapy is an excellent predictor of no further occurrence. In patients with superficial TCC, ploidy of the initial and recurrent tumor predicts for future progression. Half of those patients with stage Ta bladder cancer with two successive aneuploid bladder tumors develop muscle invasive disease within one year, while three-fourths develop advanced disease within two years after recurrence of their second aneuploid lesion.(ABSTRACT TRUNCATED AT 250 WORDS)