Efficacy and safety of pembrolizumab in metastatic urothelial carcinoma: results from KEYNOTE-045 and KEYNOTE-052 after up to 5 years of follow-up.

BACKGROUND: Immune checkpoint inhibitors are a standard therapy in metastatic urothelial carcinoma (UC). Long-term follow-up is necessary to confirm durability of response and identify further safety concerns. PATIENTS AND METHODS: In KEYNOTE-045, patients with metastatic UC that progressed on platinum-containing chemotherapy were randomly assigned 1:1 to receive pembrolizumab or investigator's choice of paclitaxel, docetaxel, or vinflunine. Primary endpoints were progression-free survival per RECIST version 1.1 by blinded independent central review (BICR) and overall survival. In KEYNOTE-052, cisplatin-ineligible patients with metastatic UC received first-line pembrolizumab. The primary endpoint was objective response rate per RECIST version 1.1 by BICR. RESULTS: A total of 542 patients (pembrolizumab, n = 270; chemotherapy, n = 272) were randomly assigned in KEYNOTE-045. The median follow-up was 62.9 months (range 58.6-70.9 months; data cut-off 1 October 2020). At 48 months, overall survival rates were 16.7% for pembrolizumab and 10.1% for chemotherapy; progression-free survival rates were 9.5% and 2.7%, respectively. The median duration of response (DOR) was 29.7 months (range 1.6+ to 60.5+ months) for pembrolizumab and 4.4 months (range 1.4+ to 63.1+ months) for chemotherapy; 36-month DOR rates were 44.4% and 28.3%, respectively. A total of 370 patients were enrolled in KEYNOTE-052. The median follow-up was 56.3 months (range 51.2-65.3 months; data cut-off 26 September 2020). The confirmed objective response rate was 28.9% (95% confidence interval 24.3-33.8), and the median DOR was 33.4 months (range 1.4+ to 60.7+ months); the 36-month DOR rate was 44.8%. Most treatment-related adverse events for pembrolizumab in either study were grade 1 or 2 and manageable, which is consistent with prior reports. CONCLUSION: With ∼5 years of follow-up, pembrolizumab monotherapy continued to demonstrate durable efficacy with no new safety signals in patients with platinum-resistant metastatic UC and as first-line therapy in cisplatin-ineligible patients. CLINICAL TRIAL REGISTRY AND ID: With ClinicalTrials.gov NCT02256436 (KEYNOTE-045); https://clinicaltrials.gov/ct2/show/NCT02256436 and NCT02335424 (KEYNOTE-052); https://clinicaltrials.gov/ct2/show/NCT02335424.

Randomized phase III KEYNOTE-045 trial of pembrolizumab versus paclitaxel, docetaxel, or vinflunine in recurrent advanced urothelial cancer: results of >2 years of follow-up.

BACKGROUND: Novel second-line treatments are needed for patients with advanced urothelial cancer (UC). Interim analysis of the phase III KEYNOTE-045 study showed a superior overall survival (OS) benefit of pembrolizumab, a programmed death 1 inhibitor, versus chemotherapy in patients with advanced UC that progressed on platinum-based chemotherapy. Here we report the long-term safety and efficacy outcomes of KEYNOTE-045. PATIENTS AND METHODS: Adult patients with histologically/cytologically confirmed UC whose disease progressed after first-line, platinum-containing chemotherapy were enrolled. Patients were randomly assigned 1 : 1 to receive pembrolizumab [200 mg every 3 weeks (Q3W)] or investigator's choice of paclitaxel (175 mg/m2 Q3W), docetaxel (75 mg/m2 Q3W), or vinflunine (320 mg/m2 Q3W). Primary end points were OS and progression-free survival (PFS) per Response Evaluation Criteria in Solid Tumors, version 1.1 (RECIST v1.1) by blinded independent central radiology review (BICR). A key secondary end point was objective response rate per RECIST v1.1 by BICR. RESULTS: A total of 542 patients were enrolled (pembrolizumab, n = 270; chemotherapy, n = 272). Median follow-up as of 26 October 2017 was 27.7 months. Median 1- and 2-year OS rates were higher with pembrolizumab (44.2% and 26.9%, respectively) than chemotherapy (29.8% and 14.3%, respectively). PFS rates did not differ between treatment arms; however, 1- and 2-year PFS rates were higher with pembrolizumab. The objective response rate was also higher with pembrolizumab (21.1% versus 11.0%). Median duration of response to pembrolizumab was not reached (range 1.6+ to 30.0+ months) versus chemotherapy (4.4 months; range 1.4+ to 29.9+ months). Pembrolizumab had lower rates of any grade (62.0% versus 90.6%) and grade ≥3 (16.5% versus 50.2%) treatment-related adverse events than chemotherapy. CONCLUSIONS: Long-term results (>2 years' follow-up) were consistent with those of previously reported analyses, demonstrating continued clinical benefit of pembrolizumab over chemotherapy for efficacy and safety for treatment of locally advanced/metastatic, platinum-refractory UC. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02256436.

Risk stratification of pT1-3N0 patients after radical cystectomy for adjuvant chemotherapy counselling.

BACKGROUND: In pT1-T3N0 urothelial carcinoma of the bladder (UCB) patients, multi-modal therapy is inconsistently recommended. The aim of the study was to develop a prognostic tool to help decision-making regarding adjuvant therapy. METHODS: We included 2145 patients with pT1-3N0 UCB after radical cystectomy (RC), naive of neoadjuvant or adjuvant therapy. The cohort was randomly split into development cohort based on the US patients (n=1067) and validation cohort based on the Europe patients (n=1078). Predictive accuracy was quantified using the concordance index. RESULTS: With a median follow-up of 45 months, 5-year recurrence-free and cancer-specific survival estimates were 68% and 73%, respectively. pT-stage, ge, lymphovascular invasion, and positive margin were significantly associated with both disease recurrence and cancer-specific mortality (P-values ≤ 0.005). The accuracies of the multivariable models at 2, 5, and 7 years for predicting disease recurrence were 67.4%, 65%, and 64.4%, respectively. Accuracies at 2, 5, and 7 years for predicting cancer-specific mortality were 69.3%, 66.4%, and 65.5%, respectively. We developed competing-risk, conditional probability nomograms. External validation revealed minor overestimation. CONCLUSION: Despite RC, a significant number of patients with pT1-3N0 UCB experience disease recurrence and ultimately die of UCB. We developed and externally validated competing-risk, conditional probability post-RC nomograms for prediction of disease recurrence and cancer-specific mortality.

Growth-regulated surface glycoproteins of human bladder cancer.

Clinical studies of human bladder cancer cells with mouse monoclonal antibodies (mAbs) have revealed two surface glycoproteins (T43 and T138) expressed by aggressive cancers and not by normal cells and a differentiation antigen (T16) expressed by normal and tumor cells of urothelial origin (Y. Fradet et al., Proc. Natl. Acad. Sci. USA, 81: 224-228, 1984; Y. Fradet et al. Cancer Res., 46: 5183-5188, 1986). To investigate further the possible association of these antigenic phenotypes with growth advantage of tumor cells, their expression, according to phases of the cell cycle and growth states (exponential and plateau phase) was studied in the human bladder carcinoma cell line T24. Expression of the p21 ras oncogene product, the Thomsen-Friedenreich antigen and the HLA class I antigen were also studied with mAbs. Multiparameter flow cytometry was used to determine antigen expression and DNA content of cells stained with mAbs and propidium iodide. Two antigens, T16 and T43, showed marked variations of their expression according to the growth status of the cells, although with an inverse profile. T16 was expressed on resting cells up to 12.5 times more than on exponentially growing cells. Conversely, T43 expression increased by a factor of 4.5 on actively proliferating cells. However, there was no preferential expression of either antigen in any one phase of the cell cycle. None of the other antigens studied, including the p21 protein, showed any density variation with either cell cycle or growth states. The results of these studies suggest that T43 may be associated with a growth advantage of tumor cells and that T16 has the characteristics of a differentiation antigen whose expression is induced on resting cells. These findings may have implications for the potential clinical use of these mAbs.

Identification of a superficial bladder tumor-associated glycoform of the carcinoembryonic antigen by monoclonal antibody 19A211.

Monoclonal antibody (mAb) 19A211 identifies a superficial bladder cancer-associated sialylated epitope expressed on a heterogeneous group of glycoproteins. These glycoproteins consist of a series of cytoplasmic glycoproteins ranging from 90 to 140 kDa present in tumor cells and, at a lower level, in normal urothelial cells, and of a membrane glycoprotein of 200 kDa observed in tumor cells only. To further characterize this antigenic system, we took advantage of the high avidity of mAb 19A211 to produce a rabbit polyclonal antibody by immunizing with antigen bound to mAb 19A211 immunoaffinity beads. The resulting polyclonal antibody specifically reacts with the 200-kDa species and not with the other glycoproteins. The biochemical characterization of this 200-kDa tumor-associated antigen showed that it is highly glycosylated (more than 50% w/w) and is anchored to the membrane via a glycosyl phosphatidylinositol link; these properties are shared with the carcinoembryonic antigen (CEA). Further experiments showed reactivity of two mAbs directed against protein epitopes of CEA with the 200-kDa component of 19A211 antigen. However, in immunohistochemistry studies of 29 colon and 23 bladder tumor specimens, no correlation was observed between expression of 19A211 and CEA antigens. Moreover, in RIAs, the intensity of expression of the 19A211 carbohydrate epitope relative to a CEA protein epitope was found to be significantly lower with CEA purified from a colon cancer cell line compared to CEA from a bladder cancer cell line. On the basis of these results, we conclude that the 200-kDa component of 19A211 antigen is a CEA glycoform preferentially expressed by superficial bladder tumors.

Clinical cancer progression in urinary bladder tumors evaluated by multiparameter flow cytometry with monoclonal antibodies. Laval University Urology Group.

Multiparameter flow cytometry studies were performed on clinical samples of human bladder tumors to simultaneously analyse DNA content and the expression of surface glycoproteins defined by monoclonal antibodies T16, Om5, T43, and T138. The results of tests performed on 80 samples of bladder irrigations and tumors from 68 patients were correlated with clinical findings at the time of sampling and with disease outcome prospectively (mean follow-up 2 years). Measuring the level of the panurothelial antigen T16 provided more precision in DNA analysis and served as an internal standard to measure the relative expression of the other cell surface antigens studied. The panel of monoclonal antibodies improved the analytical capacity to study the heterogeneity of antigenic phenotypes within individual samples. Aneuploidy frequently correlated with high stage cancers and with a high rate of clinical cancer progression defined as metastasis or death by cancer. However ploidy was not an entirely reliable prognostic indicator since a significant proportion of Ta and T1 nonprogressing tumors were aneuploid, while in 6/20 cases of cancer progression, the samples were near diploid. Contrary to Om5, T43 and T138 antigens were expressed significantly more often on aneuploid samples, although they appear to provide additional information. T138 was positive on 17/18 samples from patients with high stage cancers of which five were near diploid. It was also positive on 4/5 samples from patients with Ta and T1 tumors in whom disease progressed to metastasis and death. Overall, the expression of T138 antigen was a better single indicator of clinical cancer progression than was ploidy. Further stratification was obtained with combined results of DNA and T138 antigen studies. Within the near diploid group, the incidence of bladder cancer death was 0/26 for T138 negative and 5/13 (38%) for T138-positive patients (P less than 0.01). In the aneuploid group incidence of bladder cancer death was 2/10 (20%) for T138-negative and 12/19 (63%) for T138-positive patients (P less than 0.05). These results suggest that simultaneous flow cytometry measurements of DNA and surface antigens may better assess the prognostic behavior of human bladder tumors.

Cell surface antigens of human bladder tumors: definition of tumor subsets by monoclonal antibodies and correlation with growth characteristics.

Normal human urothelium and tumors of urothelial origin were analyzed with a panel of seven mouse monoclonal antibodies that identify surface antigens of cultured bladder cancer cell lines. Three categories of antigens were defined on the basis of differential expression on normal urothelium versus bladder tumors. Om5 (a category 1 antigen) is a highly restricted, differentiation antigen detected in the normal urothelium of 50-60% individuals. No other normal cell type in Om5- or Om5+ individuals expresses Om5. The incidence of Om5 expression in superficial bladder tumors is significantly higher (88%) than in normal urothelium, whereas its expression in invasive or metastatic tumors is far lower (20%), suggesting Om5 gain/loss in bladder tumors. Paired biopsies of normal urothelium and bladder tumors from the same individuals have shown Om5 induction in the superficial bladder tumors of Om5- individuals and Om5 loss in invasive bladder cancers of Om5+ individuals. Category 2 antigens (T43, T138, T23) are not expressed by normal urothelium or most superficial bladder tumors but are detected on a high proportion of invasive or metastatic bladder tumors, indicating that category 2 antigens are associated with late stages of tumor progression. Category 3 antigens (T16, T87, J143) provide lineage markers for normal or neoplastic cells of urothelial origin, being found on normal urothelium and virtually all bladder tumors. Thus, differential expression of category 1 and 2 antigens divide bladder tumors into distinct subsets, and these subsets correlate with pathological and clinical features of the disease.

Antibody drug carrier for immunotherapy of superficial bladder cancer: ultrastructural studies.

Superficial bladder cancer represents a promising target for intravesical, antibody-guided therapy. The construction of an optimum antibody-cytotoxic drug conjugate depends mostly on the appropriate selection of a monoclonal antibody (mAb). We have used immunogold labeling and SEM to specifically map the distribution of antigens expressed on three bladder cancer cell lines and on the luminal surface of biopsies from human transitional cell carcinoma of various grades and from normal bladder mucosa. The 48-127 mAb, which recognizes a M(r) 54,000 surface glycoprotein (gp54), was found to be very promising as a potential drug carrier. This antibody reacts with the surface of cells from low- and high-grade tumors; it does not react with the normal urothelium. Labeling of normal bladder mucosa was observed, however, on microvillous intermediate urothelial cells occasionally exposed by small areas of desquamation. The 48-127 mAb could target drugs to all areas of transformed urothelium while avoiding drug delivery to the normal, undesquamated bladder mucosa. Kinetics of gp54/48-127/gold complexes were tested in vitro with T24 and RT4 human bladder carcinoma cell lines incubated in the presence of the 48-127 mAb directly conjugated with 17.7-nm gold particles. Internalization of the gp54/48-127/gold complex was readily demonstrated by transmission electron microscopy. These results suggest that the 48-127 mAb represents a valuable drug carrier for intravesical therapy, allowing specific tumor targeting and internalization of various cytotoxic agents.

Effect of intravesical Bacillus Calmette-Guérin on detection of a urothelial differentiation antigen in exfoliated cells of carcinoma in situ of the human urinary bladder.

Flow cytometry was used to detect and quantify expression of a urothelial differentiation antigen (Om5) and nuclear DNA in exfoliated epithelial cells of the urinary bladder from 15 patients with nonpapillary carcinoma in situ during and after intravesical therapy with Bacillus Calmette-Guérin (BCG). Before BCG treatment exfoliated cells reacting with the mouse monoclonal antibody Om5 were found in 13 cases. Following treatment Om5 positive cells were still present in 9 cases but 4 patients who had had Om5 positive cells prior to BCG therapy no longer had detectable antigen-positive cells after therapy. Thus intravesical BCG therapy can alter detection of a urothelial differentiation antigen in exfoliated bladder epithelial cells. It is not certain whether this antigen or other differentiation antigens measured by flow cytometry will advance our present techniques for assessing effects of therapy on carcinoma in situ and other bladder tumors. However, five of nine patients showing persistence of Om5 positive cells after therapy were found to have recurrent tumor by biopsy and two others had positive cytology (median follow-up, 13 months). None of the four without detectable antigen-positive cells after therapy had clinical evidence of tumor by cystoscopy, biopsy, or cytology (median follow-up, 12 months). It now appears feasible and desirable to initiate clinical investigations of this and other differentiation antigens in combination with DNA by flow cytometry of bladder irrigation specimens.

Four tumor suppressor loci on chromosome 9q in bladder cancer: evidence for two novel candidate regions at 9q22.3 and 9q31.

The most common genetic alteration identified in transitional cell carcinoma (TCC) of the bladder is loss of heterozygosity (LOH) on chromosome 9. However, localization of tumor suppressor genes on 9q has been hampered by the low frequency of subchromosomal deletions. We have analysed 139 primary, initial low stage TCC of the bladder using a panel of 28 microsatellite markers spanning chromosome 9 at an average distance of 5 Mb, following a primer-extension preamplification (PEP) technique. Sixty-seven (48%) tumors showed LOH at one or more loci and partial deletions were detected in 62 (45%) tumors; apparent monosomy 9 was detected in only five (4%) tumors. Deletions were more frequent on 9q (44%) than on 9p (23%), the latter being mostly associated with 9q deletion, suggesting that alteration of genes on 9q may be an early event associated with superficial papillary tumors. Combined data from the cases with partial 9q deletions displayed four candidate regions for tumor suppressor loci, based on the frequency of deletion observed and tumors with unique deletions at these sites. In two tumors, the unique partial deletion comprised D9S12 at 9q22.3, a region encompassing loci for the Gorlin syndrome and multiple self-healing squamous epithelioma gene. In two other tumors, the single LOH was identified at the D9S172 locus at 9q31-32 where the dysautonia and Fukuyama-type congenital muscular dystrophy genes have been located. One tumor showed unique LOH at the GSN locus at 9q33, a region frequently deleted in other sporadic tumors while the fourth region of deletion was observed at 9q34 between ASS and ABL-1, in two tumors. This region is frequently deleted in tumors and encompasses the locus for the hereditary hemorrhagic telangiectasia gene. These findings suggest four target regions on 9q within which suppressor genes for TCC may reside.

Chromosome 9 deletions and recurrence of superficial bladder cancer: identification of four regions of prognostic interest.

In a previous study, loss of heterozygosity (LOH) of 28 chromosome 9 microsatellite markers was assessed on 139 Ta/T1 bladder tumors. LOH at one or more loci was detected in 67 tumors, 62 presenting subchromosomal deletions. One hundred and thirty-three of these patients have now been followed for up to 8 years. The purpose of the present study was to evaluate the potential biological significance of chromosome 9 deletions in superficial bladder tumors at initial diagnosis. High grade was associated with LOH (P=0.004). Large tumors carried more frequently 9p deletions (P=0.022). Female patients had more chromosome 9q LOH than male patients did (P=0.010). Chromosome 9 LOH at all loci was associated with an elevated risk of recurrence but four regions were associated with a particularly high risk of recurrence. Multivariate analysis taking into account grade, stage, size and number of tumors showed that tumors deleted in the regions 9ptr-p22, 9q22.3, 9q33, and 9q34 recurred significantly more rapidly than those without deletions (Recurrence rate ratio=2.32, 2.53, 2.52 and 2.43 respectively). Log-rank statistics comparing Kaplan-Meier survival curves for the same chromosomal regions confirmed the correlation (P=0.0002, 0.010, 0.002 and 0.009 respectively). Only four patients progressed to muscle-invasive disease. They all had extensive deletions on 9q but none had deletions at 9ptr-p22. This study suggests a link between chromosome 9 anomalies and recurrence of superficial bladder cancer.

Tumor-associated antigens as prognostic factors for recurrence in 382 patients with primary transitional cell carcinoma of the bladder.

This prospective study was designed to assess the prognostic value of tumor-associated antigens, designated 19A211, M344, T138, and T43, with respect to recurrence of primary superficial bladder cancer. Between September 1990 and April 1992, all patients with primary superficial bladder tumors treated by endoscopic resection in 15 participating hospitals were enrolled. Immunostaining for 19A211 and M344 was performed on paraffin-embedded material, and for T43 and T138 on frozen tissue. Antigenic expression was evaluated blindly by a single pathologist. Patients were followed up with the standard schedule of control cystoscopies. Cox regression was used to estimate hazard ratios (HRs) for first recurrence, and Poisson regression was used to estimate recurrence rate ratios and tumor rate ratios adjusted for primary tumor characteristics. By March 1994, 2254 follow-up cystoscopies had been performed on 368 of the 382 study patients, and tumor recurrence was detected in 55.7% of patients. Positivity to 19A211 was detected in 90% of primary tumors, its expression being associated with a decrease in first recurrence hazard ]HR, 0.65; 95% confidence interval (CI), 0.42-1.03] and in recurrence rate (recurrence rate ratio, 0.70; 95% CI, 0.53-0.92). Positivity to T138 was detected in 15% of tumors, and its expression was associated with an increase in first recurrence hazard (HR, 1.43; 95% CI, 0.92-2.22) and in recurrence rate (recurrence rate ratio, 1.31; 95% CI, 1.00-1.72). Positivity to M344 was detected in 71% of tumors, and its expression was associated with an increase in tumor rate (tumor rate ratio, 1.77; 95% CI, 1.41-1.97). T43 expression was not associated with recurrence end points. In conclusion, recurrence of superficial bladder cancer was associated with antigenic expression of 19A211, T138, and M344, independently of primary tumor characteristics.

Predictive value of cell cycle markers p53, MDM2, p21, and Ki-67 in superficial bladder tumor recurrence.

The aim of the study was to determine whether the expression of the cell cycle markers p53, MDM2, p21, and Ki-67 was predictive of superficial bladder cancer recurrence and to compare the relative predictive power for tumor recurrence of a cell cycle index based on the number of abnormally expressed cell cycle markers with a clinicopathological index based on primary clinical tumor characteristics. The expression of p53, MDM2, and p21 proteins and the value of the Ki-67 index were analyzed for 244 patients. One hundred ninety-four lesions were determined to be superficial papillary tumors (pTa), whereas 50 tumors invaded the lamina propria (pT1). Tumor grade was noted low (grade 1) in 83 cases and high (grades 2-3) in 161 cases. An avidin-biotin peroxidase method was performed using monoclonal antibodies against p53, MDM2, p21, and Ki-67 antigens after antigen retrieval treatment of formalin-fixed specimens. The cell cycle marker index was created using the number of abnormally expressed cell cycle markers according to the following cutoff points: p53 (>5%), MDM2 (>20%), p21 (<5%), and Ki-67 (>10%). The clinicopathological index was created using the following adverse tumor characteristics: grades G2-G3, stage pT1, multifocality, and diameter of tumors > 3 cm. Cox regression models were used to calculate the relative risks and their 95% confidence intervals associated with disease recurrence for the clinicopathological index and the cell cycle marker index. The chi2 test was performed to describe the correlation between the Ki-67 index and p53, MDM2, and p21 protein expression. Kaplan-Meier survival curves were generated to demonstrate the disease-free survival according to these two prognostic indexes. The clinicopathological index was a strong, independent predictor of disease recurrence where tumors with three or four adverse tumor characteristics at initial resection had over four times the risk of recurrence than tumors with no risk factors (P for trend = 0.0001). A strong correlation was observed between the Ki-67 index >10% and both MDM2 and p21 proteins. MDM2 was overexpressed in 106 tumors (43%), and p53 was overexpressed in 47 (19%); Ki-67 was >10% in 171 cases (70%). Thirty-nine tumors (16%) were p21 negative. The risk of recurrence increased slightly with the number of abnormally expressed cell cycle markers, but when the clinicopathological index was taken into account in multivariate analysis, the cell cycle marker index was not predictive of disease recurrence (P for trend = 0.72). The cell cycle markers studied provided no added prognostic information on disease recurrence after initial resection of papillary superficial tumors when the clinicopathological parameters were taken into account.

Reproducibility of p53 immunohistochemistry in bladder tumors. National Cancer Institute, Bladder Tumor Marker Network.

The National Cancer Institute Bladder Tumor Marker Network conducted a study to evaluate the reproducibility of immunohistochemistry for measuring p53 expression in bladder tumors. Fifty paraffin blocks (10 from each of the five network institutions) were chosen at random from among high-grade invasive primary bladder tumors. Two sections from each block were sent to each laboratory for staining and scoring, and then all sections were randomly redistributed among the laboratories for a second scoring. Intra- and interlaboratory reproducibility was assessed with regard to both staining and scoring. For overall assessments of p53 positivity, the results demonstrated that intralaboratory reproducibility was quite good. Concordance across the five participating laboratories was high for specimens exhibiting no or minimal nuclear immunostaining of tumor cells or high percentages of tumor cells with nuclear immunoreactivities. However, there was a reduced level of concordance on specimens with percentages of stained tumor cells in an intermediate range. The discordancies were due mainly to staining differences in one of the five laboratories and scoring differences in another laboratory. These results indicate that some caution must be used in comparing results across studies from different groups. Standardization of staining protocols and selection of a uniform threshold for binary interpretation of results may improve assay reproducibility between laboratories.

Biomarker study of primary nonmetastatic versus metastatic invasive bladder cancer. National Cancer Institute Bladder Tumor Marker Network.

A cohort of 109 patients with primary transitional cell carcinomas, stages T2-T3, grade 2 or higher, was identified and further divided into two groups based on lymphatic metastasis at the time of cystectomy (n = 57 cases) or absence of detectable metastatic disease over a minimum of 5 years of follow-up after cystectomy (n = 52). Blocks corresponding to the primary tumor lesions were sectioned and distributed to different laboratories to be analyzed. Immunohistochemistry on deparaffinized tissue sections was conducted for evaluation of p53 nuclear overexpression (monoclonal antibody PAb1801), assessment of proliferative index (Ki-67 antigen-monoclonal antibody MIB1), and microvascular counts (factor VIII-related antigen). DNA content/ploidy studies were performed on material obtained from thick sections. A double-blinded strategy was used for the evaluation of laboratory data versus clinical parameters. The cutoff value for p53 nuclear overexpression was > or =20% of tumor cells displaying nuclear staining. The median values for MIB1 (> or =18% of tumor nuclear cell staining) and microvascular counts (> or =40 microvessels/area screened) were used as cutoff points for these two variables. The assessment of DNA content was conducted by classifying cases as diploid, tetraploid, or aneuploid. Statistical analyses were performed using the Fisher's Exact Test (2-tailed). Results revealed that none of the markers studied had a statistically significant correlation with the end point of the study, i.e., the presence of lymph node metastatic disease, in the cohort of patients studied, although an obvious trend for p53 was noted. It is concluded that alterations of p53, Ki-67 proliferative index, microvascular counts, and ploidy are not strongly associated with lymph node status in patients affected with high-stage, high-grade bladder cancer.

Effect of neoadjuvant endocrine therapy (combined androgen blockade) on normal prostate and prostatic carcinoma. A randomized study.

The morphologic changes induced by neoadjuvant combination endocrine therapy were evaluated in prostatectomy specimens from patients diagnosed with localized prostate cancer. These patients participated in a prospective, randomized clinical trial investigating the effect of 3 months of combination therapy with flutamide and an LHRH agonist prior to radical prostatectomy versus radical prostatectomy alone. Ninety-six radical prostatectomy specimens processed according to the same protocol were evaluated without knowledge of prior treatment. Forty-seven patients were randomly assigned to the neoadjuvant combination therapy group and 49 to the control arm. Compared with the control group, several changes were strongly and significantly associated with exposure to neoadjuvant combination therapy. The nonmalignant prostatic tissue showed strong prominence and hyperplasia of the basal cell layer, accompanied by epithelial cell vacuolization and markedly reduced occurrence of prostatic intraepithelial neoplasia (p < 0.001) after combination therapy. Prostate cancer tissue, on the other hand, showed smaller nucleoli (p < 0.001), cell vacuolization (p < 0.001), rare intraluminal crystalloids (p < 0.001), higher Gleason grade (p < 0.001), lower prevalence of capsular penetration (p < 0.001), and less frequent invasion of the perineural spaces (p < 0.001) and surgical margins (p = 0.002). Tumor volume, was also reduced by more than 40% in the treated group (p = 0.007). The present findings show that preoperative endocrine combination therapy induces highly characteristic changes in both nonmalignant and cancerous prostatic tissue. Furthermore, following endocrine treatment, the surgical margins are less likely to be involved by cancer and capsular penetration is reduced.

Characterization of lymphocytotoxic antibodies in renal transplantation.

Anti-B cell, anti-T cell, and antiperipheral blood lymphocyte antibodies were investigated in the sera from 115 cadaveric kidney graft recipients pre- and post-transplantation. These antibodies were characterized: optimal temperature for cytotoxicity (4 C or 22 C), immunoglobulin class (IgG or IgM), and reactivity after platelet absorption, and thereafter defined according to their influence on the graft survival. Patients with IgM anti-B cell antibodies, reacting mostly at 4 C, the activity of which could not be removed by platelet absorption, have a prognosis of the graft as good as those with no antibody, i.e., the graft function (serum creatinine and severity of rejection) at 3 years was comparable between those two groups. However, when the anti-B cell antibodies unabsorbable on platelets are of IgG class and detected at 4 C and 22 C, the graft outcome is poorer (P less than 0.025 at 3 months). A similar prognosis is observed in patients with antiperipheral blood lymphocyte antibodies of IgG or IgM class, absorbable or not on platelets (P less than 0.05). Lymphocytotoxic antibodies of the IgG class are always associated with a poor graft outcome. On another hand, the cold anti-B cell antibodies of the IgM class are not associated with graft failure but no enhancing effect could be seen.

Immunoanatomic dissection of the human urinary tract by monoclonal antibodies.

The immunoanatomy of the human kidney and urinary tract has been analyzed by a panel of mouse anti-human monoclonal antibodies that define specific domains and structures. The differentiation antigens detected by these monoclonal antibodies represent a series of glycoproteins characteristic of different cell types. They differ from the blood group antigens and appear to be distinct from other antigens previously described within the kidney or urinary tract. The antigens recognized by these monoclonal antibodies represent an immunohistologic dissection of the human nephron. These antibodies have a broad range of potential applications in studying embryogenesis and pathogenesis of nonneoplastic and neoplastic diseases of the human kidney and urothelium.

Ha-ras codon 12 mutation in papillary tumors of the urinary-bladder - a retrospective study.

This report concerns the retrospective examination of low grade, low stage (Ta/T1) bladder tumors for the Ha-ras codon 12 G-->T mutation. The patients studied had a minimum of 5 years follow-up and were grouped into 3 categories: (i) patients with no recurring tumors, (ii) patients with recurring Ta/T1 tumors and (iii) patients who subsequently developed high grade, high stage tumors. A heminested, non-isotopic, allele-specific polymerase chain reaction (PCR) amplification assay was used. The codon 12 G-->T mutation was found in 10/27 specimens from patients with non-recurring Ta/T1 tumors; in 11/27 initial and 12/23 recurring Ta/T1 tumors, and in 5/8 initial Ta/T1 lesions and 8/12 subsequently developed high grade/stage tumors. Although there was no correlation between disease recurrence and mutation, these results indicate that a relatively large proportion of patients with Ta/T1 tumors of the bladder have cells with the Ha-ras codon 12 G-->T substitution.

Prognostic significance of nuclear DNA content and S-phase fraction by flow cytometry in primary papillary superficial bladder cancer.

This study is aimed at determining the usefulness of nuclear DNA content and S-phase fraction (SPF) to predict tumor recurrence in papillary superficial bladder cancer. Tumor DNA content and SPF were measured by flow cytometry on formalin-fixed, paraffin-embedded tissue from 199 newly diagnosed pTa/pT1 transitional cell carcinomas of patients enrolled into a multicenter prospective study from 1990 to 1992. The follow-up extended up to March 1994, and, at last follow-up, 122 (61.3%) patients have experienced at least one recurrence. After exclusion of 34 cases, whose coefficient of variation exceeded 8%, 131 (79.4%) tumors were diploid, and 34 (20.6%) were aneuploid. There was no association between tumor DNA content and time to first recurrence. Diploid tumors with low SPF (< 11%) tended to have a longer recurrence-free survival (RFS) than those with high SPF, but this difference did not reach statistical significance (P = .2833). SPF in aneuploid tumors did not add any new information. Aneuploidy was associated with higher stage (P < .001), poorer grade (P < .002), multifocality (P = .028), Her-2/neu (P = .021), and p53 (P = .033) expression. High SPF correlated with higher stage (P = .066) and higher grade (P = .025). This study shows that DNA-ploidy and SPF measured on a single superficial bladder cancer specimen are not predictive of tumor recurrence. The frequent multifocality of the disease may explain, in part, these findings.