Flow cytometry as a predictor of response and progression in patients with superficial bladder cancer treated with bacillus Calmette-Guerin

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.

[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.

Assessment of DNA flow cytometry as a surrogate end point biomarker in a bladder cancer chemoprevention trial

Although conventional cytology represents the most widely performed cytometric analysis of bladder cancer cells, DNA flow cytometry has, over the past decade, been increasingly used to evaluate cell proliferation and DNA ploidy in cells from bladder washings. We have investigated whether DNA flow cytometry and conventional cytology of epithelial cells obtained from bladder washings provide reliable surrogate endpoint biomarkers in clinical chemoprevention trials. We used cytometric and clinical data from a chemoprevention trial of the synthetic retinoid Fenretinide on 99 patients with superficial bladder cancer. A total of 642 bladder washing specimens obtained from the patients at 4 month intervals was analyzed. Intra-individual agreement and correlation of flow cytometric DNA ploidy (diploid vs. aneuploid), DNA Index, Hyper-Diploid-Fraction (proportion of cells with DNA content higher than 2C), and conventional cytologic examination, as assessed by kappa statistics and Spearman's correlation test, were poor from baseline through 24 months. Moreover, no correlation was found between DNA ploidy and cytology at each time point. The same results were obtained when the analyses were stratified by treatment group. In addition, the association between the results of bladder washing (by either DNA flow cytometry or cytology) and concomitant tumor recurrence was significant only for abnormal cytology, while neither biomarker was predictive of tumor recurrence at the subsequent visit. During the time of this study only four patients progressed to muscle-invasive bladder cancer, indicating the "low-risk" features of the patient population. We conclude that DNA flow cytometry and conventional cytology on epithelial cells obtained from bladder washings do not appear to provide suitable surrogate endpoint biomarkers during the early stages of bladder carcinogenesis.

Image analysis combined with visual cytology in the early detection of recurrent bladder carcinoma

BACKGROUND

Early detection of recurrent transitional cell carcinoma of the bladder (TCC) is important to permit early treatment, which produces maximal preservation of the bladder and maximum survival.

METHODS

This retrospective cohort study attempted to determine the period of time over which urinary DNA image analysis combined with visual cytology is useful in the early detection of recurrent TCC of the bladder. The authors believe this study is unique in that it measured the effectiveness of this test (image analysis plus visual cytology combined) at varying times before clinical diagnosis of recurrence was made. The cohort was comprised of 175 urologic patients from urologic practices across the U.S. Data, collected between January 1991 and February 1994, included cystoscopy, biopsy, DNA image analysis, and visual cytologic reports.

RESULTS

Sixty patients in the cohort were found to have active TCC whereas 115 patients had a history of, but no active, disease during the follow-up period. As expected, the sensitivity and specificity of DNA image analysis in combination with visual cytology, and DNA image analysis alone, were greatest when urinary samples were obtained close to the time of diagnosis. In general, the longer the interval from the combined tests to the time of diagnosis, the lower the sensitivity. The combined tests had predictive value up to 3 months prior to clinical diagnosis when any detectable cytologic abnormality was considered positive. At the optimal cutoff points as determined from receiver operating characteristic curves, sensitivity increased when DNA image analysis was supplemented with visual cytology.

CONCLUSIONS

The combination of DNA image analysis and visual cytology provides a better method for the early detection of recurrent TCC than DNA image analysis alone. This test potentially may be useful in providing information regarding bladder tumor recurrence up to 3 months prior to clinical evidence of disease.

Flow cytometry in diagnostic cytology

Flow cytometry (FCM) is a useful adjunct to cytologic examination, because the quantitative biochemical information it provides complements the morphologic information gained during visual examination. It aids in the interpretation of bladder washings, and is particularly useful for the assessment of lymphoid lesions, whether they originate from fine-needle aspiration, cerebrospinal fluid, or effusions. Optimal use of FCM frequently requires assessment of more than one parameter; simultaneous use of cell differentiation markers and nuclear DNA quantitation is often significantly more useful than either alone. Despite the utility of FCM, however, the potential for future development appears to be limited. Improvements in image cytometry allow reasonable assessment of ploidy and S-fraction to be made from specimens prepared on glass slides. Multiparameter measurements may also be accomplished with imaging techniques, which allow the further advantage of visual identification of cells with equivocal morphologic changes. The development of artificial intelligence methods for use with imaging technology has also significantly exceeded that of FCM. Finally, image cytometry is often more useful for samples with few cells. Other challenges are posed by immunocytochemical methods which compete with flow cytometry as tools for assessment of proliferation. Given the relatively high cost of FCM instrumentation, survival of FCM as an ancillary technique in cytopathology will require further technical refinements to offset the advantages currently associated with image cytometry and immunocytochemistry.

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.

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.

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.

Bladder wash flow cytometry in transitional cell carcinoma: useful or misleading?

To evaluate the practical usefulness of flow cytometry (FC) applied to bladder wash specimens for the diagnosis of transitional cell carcinoma (TCC), a study was conducted on a series of 101 cases comprising 60 patients with tumor or with past history of TCC, and a control group of 41 patients undergoing cystoscopy for causes other than TCC in which the absence of tumor was confirmed after 1 year of follow-up. When results of the 33 patients with tumor were compared with those of the control group, FC gave low specificity and positive predictive values (54% and 58%, respectively). Conventional cytologic study was superior to FC in this setting. Although the combination of both techniques increased the sensitivity for low-grade tumors, specificity remained lower than that of cytologic study alone. Otherwise, when considering only the cases with a past history of TCC, results of FC were superior to those of cytologic examination, and the combination of both techniques gave high sensitivity and negative predictive values (94% and 93%, respectively). In conclusion, the use of FC in a general diagnostic setting could be misleading, whereas in the follow-up of patients with a history of TCC it becomes a useful adjunct to cytologic study in order to obtain a high diagnostic performance that could allow cystoscopies to be spaced out in these patients.

Bladder cancer: advances in biology and treatment

Integrating systemic chemotherapy in the treatment of patients with invasive bladder cancer is essential to improve survival because the majority of deaths are from systemic relapse. However, as experience with invasive tumors evolves, it is clear that treatment recommendations need to be tailored to an individual patient based on metastatic risk and, ideally, sensitivity to treatment. For those with tumors that do not extend through the bladder wall, standard therapy remains radical surgery. Nevertheless, encouraging results are being reported with increasing frequency using strategies designed to preserve bladder function through a variety of means. Crucial to the recommendation of a specific approach for an individual is improving our ability to define prognosis prior to initiating treatment. Patients with a high risk of systemic recurrence generally require chemotherapy, although the optimal route of integration, pre vs. post-operatively, remains controversial. In those patients who require it, chemotherapy can be administered more safely with the concomitant administration of hematopoietic growth factors. These factors alone, however, are unlikely to improve overall survival. Crucial to the latter effort will be the identification of more active agents, improving our understanding of intrinsic and acquired resistance to chemotherapy, and better delivery of the chemotherapeutic agents currently available. Of equal importance, is the enrollment of patients in clinical trials. These can include large scale randomized comparisons with using a survival end-point, as well as new therapies in high risk populations. The latter would include patients with advanced T3b, T4 and N+ disease, with a high risk of metastatic failure, and low complete response proportions to presently available regimens.

Hypocellular bladder wash specimens and their clinical significance

Bladder wash flow cytometry specimens containing less than 1,000 cells were defined as hypocellular. Between June 1981 and December 1990, 5,676 bladder wash flow cytometry specimens were collected, of which 142 (2.5%) were deemed hypocellular. Of the 132 evaluable patients with hypocellular specimens 34 (30%) had documented evidence of carcinoma compared to 52% for the entire population. Among the 34 patients 30 had transitional cell carcinoma, of which 12 were carcinoma in situ, 9 stage Ta or T1 and 9 stage T2 or greater. Thus, there was no obvious relationship between stage or grade of carcinoma versus probability of a hypocellular specimen. Differences in irrigation techniques of different urologists in the operating room using general anesthesia versus catheter and cystoscopic irrigation in the outpatient clinic are discussed as possible explanations for the hypocellular specimens.

Flow cytometry for detection and evaluation of urinary bladder carcinoma

Flow Cytometry (FCM) DNA assays of bladder irrigation specimens are now recognized as a clinically useful and reliable means of detecting and monitoring carcinoma of the bladder. This technique, which identifies carcinoma by the presence of an aneuploid population of cells, can be carried out on specimens obtained in an outpatient or hospital setting and is easily performed in any medium-sized laboratory. It is most sensitive to superficial and high grade tumors. Overall, nearly 80% of superficial carcinomas of bladder will have positive flow cytometry, comparing very favorably with conventional cytology. Until now, the widest clinical application of FCM has been in monitoring the conservative treatment of stage 0-1 flat and papillary carcinomas, but newly developed dual parameter measurements are capable of quantifying proliferative activity, oncogene expression, growth factor receptors, and other cellular features that may better characterize the biologic potential of these tumors and can be expected to aid in the selection and timing of treatment.

The predictive value of flow cytometry and urinary cytology in the followup of patients with transitional cell carcinoma of the bladder

To determine the predictive value of flow cytometric deoxyribonucleic acid (DNA) ploidy and urine cytology in patients with superficial transitional cell carcinoma of the bladder, a retrospective analysis was performed on 181 patients who presented for evaluation of presumed superficial transitional cell carcinoma of the bladder. Of the patients 91 were confirmed to have superficial transitional cell carcinoma and were systematically followed with cystoscopy, flow cytometry and urine cytology from 1984 until 1989. They underwent 637 evaluations (mean 7 evaluations per patient). At initial evaluation, flow cytometry had 81% sensitivity and 57% specificity, while urine cytology was 75% sensitive and 94% specific. During the followup flow cytometry was 76% sensitive and 36% specific. Urine cytology was less sensitive (40%) but more specific (81%) than flow cytometry in followup evaluation. These results were similar whether intravesical chemotherapy or bacillus Calmette-Guerin was administered. To ascertain whether false positive flow cytometry represented early detection of recurrent transitional cell carcinoma not apparent at cystoscopy, patients with positive flow cytometry and urine cytology were followed longitudinally. False positive flow cytometry and urine cytology were equally predictive of recurrent transitional cell carcinoma progressively with time. However, for any given examination flow cytometry was more likely to detect and predict recurrent transitional cell carcinoma. At 4 years the bladder transitional cell carcinoma incidence for false positive flow cytometry and urine cytology was 87% and 84%, respectively.

Centrifugal separation of carcinoma or atypical cells in voided urine

A simple density gradient method was used to separate atypical and cancer cells from non-cancer cells in voided urine from patients with transitional cell atypia (moderate and grave atypia) and bladder cancer (squamous cell carcinoma and transitional cell carcinoma). Prior to cell separation, the Saccomanno preserved cells were dispersed by homogenization. After cell separation (5 min x 1400 rpm), atypical and cancer cells were enriched up to 20-fold. Also, most of the leucocytes (68-98%) and squamous cells (47-82%) were absent from density gradient specimen fractions containing the largest percentages of atypical and cancer cells. Peak purity ranges of atypical or cancer cells from different sample classes showed a large degree of overlap. This permitted the pooling of density gradient fractions enriched for atypical or cancer cells, thus increasing the efficiency of the method. Also, following centrifugation, the Papanicolaou-stained specimen fractions showed less background staining than the unprocessed controls, and the cells retained diagnostic morphologic features. We infer that this method may be a useful, low-cost approach for the morphologic study of developing cancers, not only from the urinary bladder, but also from the respiratory tract.

Deoxyribonucleic acid flow cytometry in invasive bladder carcinoma: a possible predictor for successful bladder preservation following transurethral surgery and chemotherapy-radiotherapy

Tumor deoxyribonucleic acid (DNA) ploidy was evaluated as an objective parameter that may correlate better with the responsiveness of bladder cancer to chemotherapy plus radiotherapy than do clinical features or histopathological subtypes. A total of 40 patients with localized muscle-invading bladder cancer (clinical stages T2 to T4) underwent prospective treatment on a potential bladder preserving protocol. Tumors of 37 of the 40 patients were analyzed by DNA flow cytometry of multiple paraffin embedded specimens. Transurethral resection, neoadjuvant chemotherapy and 40 Gy. radiotherapy plus cisplatin were followed by urological reevaluation of the tumor (a complete response required a negative biopsy and a negative urine cytology study). A total of 7 noncomplete response patients underwent immediate radical cystectomy whereas the full bladder sparing treatment (radiotherapy to 64.80 Gy. plus cisplatin) was given to 23 complete response patients and 7 noncomplete response patients who were unsuited for surgery. Of the tumors 22 (59%) were purely aneuploid and 10 (27%) were purely diploid. Five tumors contained aneuploid and diploid patterns in different tumor specimens (partly diploid). Current status with a 30-month median followup in surviving patients includes an 82% overall survival rate in the aneuploid group versus 47% in the diploid/partly diploid group. Of all the patients 68% are free of invasive tumor: 82% in the aneuploid group versus 47% in the diploid/partly diploid group. By multivariate analysis pure aneuploidy was significantly (p = 0.05) correlated with freedom from invasive tumor in the bladder (either as persistence or as recurrence) and approached significance (p = 0.08) in correlation with overall patient survival. A longer observation time will be required to confirm this unexpectedly good outcome for patients with pure aneuploid tumors. We hypothesize that pretreatment DNA ploidy status may become a clinically useful prognostic factor in selecting patients for successful treatment with transurethral surgery and neoadjuvant chemotherapy plus radiotherapy.

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)

DNA analysis in predicting survival of irradiated patients with transitional cell carcinoma of bladder

A total of 115 patients with invasive transitional cell carcinoma of the bladder underwent radical radiotherapy between 1975 and 1986 and were followed up until the end of 1990. Apart from routine clinical observations, flow cytometric DNA measurements made on fresh tumour material were available for analysis. Actuarial cancer-free survival controlling for response to treatment was analysed with the log-rank test, bivariate and multivariate analyses using Cox's stepwise regression model on probable prognostic factors. The overall actuarial 5-year cancer-free survival rate was 30%. Survival was significantly correlated with response to treatment: 59% for patients with complete regression and 5% for those with residual tumour. Prognostic factors that significantly correlated with death from cancer were advanced stage, large size, incomplete resection, ureteric obstruction, anaemia, carcinoma in situ grade 3 and occurrence of more than one aneuploid cell population. However, only 3 of these factors were of independent power in the multivariate analysis: stage, size and carcinoma in situ. Of 21 patients with a history of primary or secondary carcinoma in situ, 19 died from cancer during follow-up: 18 of the 21 patients had tumours that were aneuploid with more than one aneuploid cell population. It is concluded that curative radiotherapy can be successful only in patients with less advanced tumours assessed according to clinical stage and size, aneuploid tumours with not more than one aneuploid cell line, no carcinoma in situ, no ureteric obstruction, and in whom a complete transurethral resection of the exophytic tumour is possible.

DNA slit-scan flow cytometry of bladder irrigation specimens and the importance of recognizing urothelial cells

DNA slit-scan flow cytometry was used to analyze 150 bladder irrigation specimens from 83 patients. Specimens were categorized into groups based on cystoscopy, histology, and cytopathology. Cells were stained for DNA with propidium iodide using a whole cell protocol. Non-specific fluorescence in the cytoplasm of some urothelial cells together with differential DNA staining of cell types in certain specimens was noted. DNA frequency distributions were analyzed using a semi-automated technique. Data were gated using slit-scan morphological features to remove cellular debris, multiple nuclei, and cells exhibiting nonspecific cytoplasmic fluorescence. Specimens were classified abnormal if they were aneuploid or had a hyperdiploid fraction (HDF) greater than 8%. The sensitivity to abnormality was 89% for grade 3 transitional cell carcinoma (TCC), 70% for grade 2 TCC, and 67% for grade 1 TCC. Specificity was 61%. Specimen data were then reprocessed using slit-scan morphological features to enrich for urothelial cells. The urothelial cells were identified by the ratio of nuclear diameter to cell diameter. This method was found to be in good agreement with immunofluorescent labeling of urothelial cells using the urothelium-selective T16 monoclonal antibody. The sensitivity to abnormality remained 89% for grade 3 TCC and 70% for grade 2 TCC, but fell to 52% for grade 1 TCC. Specificity for the urothelial cell enriched data increased to 77%. Reprocessing of data to enrich for urothelial elements resulted in 16 fewer specimens with an aneuploid DNA distribution and 2 fewer specimens with increased HDF.(ABSTRACT TRUNCATED AT 250 WORDS)

Flow cytometric DNA analysis after immunoselection of bladder tumor cells with monoclonal antibody DU83.21

Adequate preservation of neoplastic cells and the elimination of interference by inflammatory cells in measuring tumor cell DNA content represent two important objectives necessary for accurate flow cytometric analysis of bladder carcinomas. An experimental model consisting of a mixture of cultured bladder carcinoma cells (T24) and human buffy-coat (BC) cells was used to evaluate various preservatives and an anti-bladder carcinoma monoclonal antibody (MoAb), DU83.21, for separating inflammatory cells (BC cells) from T24 cells. A final concentration of 25% ethanol was found to be the most effective preservative of several tested. After incubation with the MoAb DU83.21 and propidium iodide (DNA stain), the T24 cells could be separated from the BC cells, permitting accurate DNA analysis of the tumor cells. Application of this system to specimens from bladder cancer patients enhanced the detection and DNA analysis of the tumor cell populations.