PREDICTIVE VALUE OF p53 AND pRb IMMUNOSTAINING IN LOCALLY ADVANCED BLADDER CANCER TREATED WITH CYSTECTOMY

Prognostic markers in pT3 bladder cancer: A study from the international bladder cancer tissue microarray project

PURPOSE

We evaluated the prognostic value of 10 putative tumor markers by immunohistochemistry in a large multi-institutional cohort of patients with locally advanced urothelial cancer of the bladder (UCB) with the aim to validate their clinical value and to harmonize protocols for their evaluation.

MATERIALS AND METHODS

Primary tumor specimens from 576 patients with pathologic (p)T3 UCB were collected from 24 institutions in North America and Europe. Three replicate 0.6-mm core diameter samples were collected for the construction of a tissue microarray (TMA). Immunohistochemistry (IHC) for 10 previously described tumor markers was performed and scored at 3 laboratories independently according to a standardized protocol. Associations between marker positivity and freedom from recurrence (FFR) or overall survival (OS) were analyzed separately for each individual laboratory using Cox regression analysis.

RESULTS

The overall agreement of the IHC scoring among laboratories was poor. Correlation among the 3 laboratories varied across the 10 markers. There was generally a lack of association between the individual markers and FFR or OS. The number of altered cell cycle regulators (p53, Rb, and p21) was associated with increased risk of cancer recurrence (P < 0.032). There was no clear pattern in the relationship between the percentage of markers altered in an 8-marker panel and FFR or OS.

CONCLUSIONS

This large international TMA of locally advanced (pT3) UCB suggests that altered expression of p53, Rb, and p21 is associated with worse outcome. However this study also highlights limitations in the reproducibility of IHC even in the most expert hands.

Gender Specific Differences in Disease-Free, Cancer Specific and Overall Survival after Radical Cystectomy for Bladder Cancer: A Systematic Review and Meta-Analysis

PURPOSE

We summarize the evidence on gender specific differences in disease-free, cancer specific and overall survival after radical cystectomy for bladder cancer.

MATERIALS AND METHODS

We performed a systematic literature search of MEDLINE®, Embase® and the Cochrane Library in July 2017. Studies evaluating gender specific differences in disease-free, cancer specific or overall survival after radical cystectomy for bladder cancer were included in study. Analyses included random effect meta-analysis, subgroup analyses, meta-influence and cumulative meta-analyses. Funnel plots and the Egger test were used to assess publication bias.

RESULTS

Of the 3,868 studies identified during the literature search 59 published between 1998 and 2017 were included in analysis. Of the studies 30 in a total of 38,321 patients evaluated disease-free survival, 44 in a total of 69,666 evaluated cancer specific survival and 26 in a total of 30,039 evaluated overall survival. Random effect meta-analyses revealed decreased disease-free, cancer specific survival and overall survival in female patients than in their male counterparts. Pooled estimates showed a HR of 1.16 (95% CI 1.06-1.27, p = 0.0018) for disease-free survival, 1.23 (95% CI 1.15-1.31, p <0.001) for cancer specific survival and 1.08 (95% CI 1.03-1.12, p = 0.0004) for overall survival. Subgroup analyses confirmed impaired disease-free, cancer specific and overall survival in female patients in all strata. Publication bias was evident only for studies of cancer specific survival (Egger test p = 0.0029). After adjusting for publication bias by the trim and fill method the corrected pooled estimated HR of cancer specific survival was 1.13 (95% CI 1.05-1.21, p = 0.0012).

CONCLUSIONS

Female patients who underwent radical cystectomy for bladder cancer demonstrated worse disease-free, cancer specific and overall survival than their male counterparts. The multifactorial etiology might include epidemiological differences, gender specific health care discrepancies and hormonal influences.

Markers of bladder cancer State of the art

Biomarkers are increasingly being applied to the clinical management of patients with bladder cancer. The biomarkers in current clinical use focus on bladder cancer detection. Biomarkers for prognosis and as intermediate endpoints for chemoprevention are being evaluated in clinical trials. This review provides an overview of the performance characteristics of current clinical markers and other markers that are currently under evaluation.

RB family members as predictive and prognostic factors in human cancer

The retinoblastoma family members--pRb, pRb2/p130 and p107--are tumor suppressor genes involved in controlling four major cellular processes: growth arrest, apoptosis, differentiation and angiogenesis. Molecular genetic studies have identified abnormalities of these tumor suppressor genes in a large proportion of human cancers. These genetic alterations have emerged as significant factors in the pathogenesis and progression of many types of tumors and are therefore likely to provide relevant information to assess risk in cancer patients. There is a pressing clinical need to identify prognostic and predictive factors for patients with cancer, because there is an undeniable importance in being able to determine which patients will have a favorable outcome without further therapy (prognostic factor) and which will need some additional treatment (predictive factor). This review examines the predictive and/or prognostic role of each retinoblastoma family member in human cancer.

Management of stage T1 tumors of the bladder: International Consensus Panel

The International Consensus Panel on T1 bladder tumors markers reviewed the subject from a clinical perspective. From diagnosis to treatment decisions, what are the important issues in the management of a new patient? The assessment of prognostic factors for progression requires optimal resection and documentation. The role of immediate adjuvant intravesical chemotherapy after resection remains controversial. How often should the upper tract be assessed for tumor recurrence? The decision on whether to attempt bladder conservation with intravesical therapy or to perform a cystectomy is the most difficult issue in the management of superficial bladder cancer today. Finally, what therapies exist if initial intravesical bacille Calmette-Guérin fails to eradicate the disease or prevent recurrence? The panel thoroughly explored all these subjects and has made recommendations with supporting evidence.

P53 as a prognostic marker for bladder cancer: a meta-analysis and review

BACKGROUND

P53 is the most widely investigated molecular marker in bladder cancer. We aimed to review comprehensively the evidence for use of changes in P53 to predict bladder-cancer recurrence, progression, and mortality.

METHODS

We reviewed 168 publications from 117 studies. Estimates of significance were extracted from association tests, and hazard ratios with 95% CI from actuarial curves and Cox regression analyses. A meta-analysis was done on the studies that applied Cox models.

FINDINGS

The methods used to assess significance varied widely between studies. 27% (nine of 34) of studies that assessed the prognostic value of P53 overexpression in recurrence by use of multivariate tests showed a significant association. The corresponding values for progression and mortality were 50% (12 of 24) and 29% (ten of 35), respectively. In the studies that used Cox models, the overall risk of recurrence was 1.6 (95% CI 1.2-2.1), of progression was 3.1 (1.9-4.9), and of mortality was 1.4 (1.2-1.7). These findings could be overestimates because of publication and reporting bias.

INTERPRETATION

After 10 years of research, evidence is not sufficient to conclude whether changes in P53 act as markers of outcome in patients with bladder cancer.

Association of positive serum anti-p53 antibodies with poor prognosis in bladder cancer patients

AIMS

To assess the association of serum anti-p53 antibodies and overexpression of tumor p53 protein with survival and prognostic factors in patients with urinary bladder tumors.

METHODS

Seventy-six patients with transitional cell carcinoma of the urinary bladder were assessed prospectively (Ta, 18; T(1), 30; > or =T(2), 28). Serum anti-p53 antibodies were detected by enzyme-linked immunosorbent assay. Tumor p53 gene overexpression was assessed by immunohistochemical staining. The mean follow-up time was 34 months.

RESULTS

Serum anti-p53 antibodies were positive in 25 patients (33%). Overexpression of tumor p53 protein was positive in 41 patients (54%). There was an association between the presence of serum anti-p53 antibodies and tumor p53 gene overexpression (P = 0.001). The total survival of the patients with positive serum anti-p53 antibodies was shorter than the patients with positive tumor p53 gene overexpression (P < 0.001, P = 0.344, respectively). In the multivariate survival analysis, both tumor stage and serum-p53 antibodies were found to be independent survival predictors (P = 0.004, P = 0.006, respectively).

CONCLUSION

Serum anti-p53 antibody positive tumors had a worse prognosis than those with negative serum levels, regardless of the p53 status of the tumor.

Correlation of Metastasis Related Gene Expression and Relapse-Free Survival in Patients With Locally Advanced Bladder Cancer Treated With Cystectomy and Chemotherapy

PURPOSE

Patients with locally advanced (ie clinically extravesical) transitional cell carcinoma are at high risk for recurrence after cystectomy. Although randomized trials have established an incremental benefit from the addition of chemotherapy in this setting, many patients still have disease relapse, and therefore it is necessary to determine patient and tumor characteristics that correlate with outcome in this setting. We investigated the tumor expression of several metastasis related genes and the association of gene expression with disease specific survival of patients with locally advanced transitional cell carcinoma treated randomized to either neoadjuvant or adjuvant chemotherapy and radical cystectomy.

MATERIALS AND METHODS

Archival paraffin embedded specimens were available for 64 patients enrolled in a clinical trial of the methotrexate, vinblastine, doxorubicin and cisplatin regimen and cystectomy. Only samples obtained before exposure to chemotherapy were studied. The expression of several metastasis related genes, including basic fibroblast growth factor, vascular endothelial growth factor (VEGF), interleukin-8, matrix metalloproteinase (MMP)-9, and E-cadherin were assayed on paraffin sections using a colorimetric in situ hybridization assay.

RESULTS

Expression of basic fibroblast growth factor, interleukin-8 and MMP-9 did not correlate with outcome. Expression of VEGF and E-cadherin were strongly related to disease specific survival. In addition, the ratio of MMP-9-to-E-cadherin was strongly prognostic for disease specific survival.

CONCLUSIONS

These data advance the hypotheses that VEGF expression and an "invasive phenotype" characterized by the ratio of MMP-9-to-E-cadherin expression are mechanistically relevant to clinically aggressive locally advanced bladder cancers that are not cured by currently available combined modality treatment. Thus, in our view there is a compelling rationale to target these aspects of the malignant phenotype in this patient population.

Identification of the novel role of pRB in eye cancer

Cancer of the eye, though relatively rare, can involve multiple areas. Retinoblastoma is the most common primary intraocular cancer in children, with 3-7 cases per million people per year worldwide. Uveal melanoma is the most common primary intraocular cancer in adults, predominately in whites, with annual incidence of six per million people in the United States and Europe. Despite the rarity of retinoblastoma, Knudson's two-hit hypothesis to explain its genesis was substantiated by elegant genetic studies and is viewed as a turning point in cancer research. pRB plays an important role in cell cycle and apoptosis, performing its function through interaction with transcription factors, p53, and MDM2. Unfortunately, advances in eye cancer treatment have not paralleled those in treatment of other sites of cancer. In spite of higher accuracy in early diagnosis, eye-cancer-specific mortalities have remained unchanged for decades, while overall cancer mortality rates have dramatically declined. An extensive literature search revealed that, except for retinoblastoma, few investigations had been done on the pRB pathway in eye cancers even though altered pRB expression has been associated with a number of cancers. Early detection of eye cancer is critical for the prognosis of both vision and survival. Mutation analysis should become an integral part of future management of patients with eye cancer. Characterization of the mutational pattern of RB1 is crucial in identifying predisposition for cancer of many sites including the eye. Furthermore, cost-effective and efficient genetic mutation screen testing methods, which can be used to categorize mutant RB1 carriers, are needed. Illumination of genetic insights can guide clinicians to develop a rational strategy for cancer treatment and help predict prognosis in cancer patients.

Prognostic value of p53 overexpression in bladder tumors treated with Bacillus Calmette-Guerin

Bacillus Calmette-Guerin intravesical therapy is the standard treatment of superficial bladder tumors at high risk of recurrence and progression to muscle-invasion disease. To date, there is no well established predictive factor of response to Bacillus Calmette-Guerin intravesical therapy. The prognostic value of p53 overexpression in bladder tumors is controversial. Most investigators have found no correlation between p53 status assessed before Bacillus Calmette-Guerin intravesical therapy and patient outcome. On the other hand, it is acknowledged that the persistence of p53 overexpression after Bacillus Calmette-Guerin intravesical therapy is predictive of progression in patients treated for carcinoma in situ. Since conflicting data have been reported, further evaluation of the impact of p53 overexpression in patients treated with Bacillus Calmette-Guerin intravesical therapy for bladder carcinoma is required.

Multivariate analysis of survival, recurrence, progression and development of mestastasis in T1 and T2a transitional cell bladder carcinoma

BACKGROUND

Determination of prognosis factors associated with survival, recurrence, progression, and development of metastasis in T1 and T2a transitional cell carcinoma (TCC) of the bladder is discussed.

METHODS

A study was conducted of a group of 210 patients with primary bladder TCC at classification T1 (n = 175) and T2aN0M0 (n = 35). A total of 177 variables were studied in each patient. The monoclonal antibodies used were the following: DO7 (p53) and MIB-1 (Ki-67). Prognosis was obtained using Kaplan-Meier methodology and Cox proportional hazards model.

RESULTS

The average follow-up period was 6.7 years. Cancer-related survival rates at 5 and 10 years were 82.96% and 74.78%, respectively. The independent survival variables were the following: age and expression of p53. Recurrence free survival at 5 and 10 years stood at 51.80% and 42.71%, respectively. The independent recurrence variables were T2a classification, tumor multifocality, tumor size of greater than 3 cm, carcinoma in situ in random biopsy, and expression of Ki-67. Progression free survival rates at 5 and 10 years were 75.31% and 69.16%, respectively. The independent progression variables were age, T2a classification, and expression of p53. Metastasis free survival rates at 5 and 10 years stood at 87.23% and 84.55%, respectively. The expression of p53 was the sole variable to provide an independent prediction of metastasis.

CONCLUSIONS

The expression of p53 clearly has an independent effect on the prediction of survival, progression and development of metastasis, showing a dose-response effect. Tumor multifocality and T2a classification are the variables that best predict recurrence.

Prognostic value of p53 overexpression in T1G3 bladder tumors treated with bacillus Calmette-Guérin therapy

OBJECTIVES

To evaluate the correlation between the overexpression of mutant protein p53 and disease recurrence and progression in patients treated with bacillus Calmette-Guérin (BCG) intravesical therapy for T1G3 bladder cancer.

METHODS

We analyzed the outcome of 29 consecutive patients treated for T1G3 bladder tumor with transurethral resection. Patients previously treated for a bladder tumor, those who underwent incomplete resection, and those in whom no assessment of the muscle cell layer was possible were excluded from the study. p53 overexpression was determined using monoclonal p53-DO7 antibody, with a 20% cutoff for definition of positivity. After the initial transurethral resection, all patients were treated with Pasteur BCG (75 mg in 50 mL saline), weekly for 6 weeks. The correlation between p53 overexpression and disease recurrence and progression was assessed by the Fisher exact test.

RESULTS

The median follow-up was 36.7 months (range 1 to 108). Of the 29 patients, 18 (62.1%) were p53 positive and 11 (37.9%) were p53 negative. Both groups were similar according to age, tumoral substage (T1a/T1b), association with carcinoma in situ, multifocality, and length of follow-up. The recurrence rate was 54.4% in the p53-negative group versus 38.9% in the p53-positive group (P = 0.47). The progression rate was 18.2% in the p53-negative group versus 33.3% in the p53-positive group (P = 0.67).

CONCLUSIONS

These findings suggest that overexpression of p53, as determined immunohistochemically, has no predictive value for recurrence and progression in T1G3 bladder cancers treated with intravesical BCG.

Use of markers in defining urothelial premalignant and malignant conditions

Markers have revealed the presence of phenotypically abnormal areas in histologically benign urothelium in bladders containing transitional cell carcinomas. This finding strongly suggests that at least some bladder cancers are associated with changes in the field and that markers can detect these lesions before they reach a grossly malignant stage. Markers have been used clinically for the detection of cancer in patients who are under regular surveillance for recurrence of bladder cancer. Much less information is available regarding the use of markers to detect bladder cancer without a prior history of the disease and for the prediction of which tumors are biologically more aggressive. However, ongoing clinical trials are addressing the latter issue. The type of specimen and its preparation will determine what type of markers can be analyzed. Although marker performance is based upon sensitivity and specificity, the prevalence of bladder cancer in the population being tested will dramatically affect the positive predictive value of an assay. Markers with high positive predictive value are indicators for interventions, such as biopsy, while markers with high negative specific values are useful for avoiding interventions. Cytology is used to detect occult high-grade neoplasms such as carcinoma in situ. While not yet clinically validated, tests with high negative predictive value could be used to decrease the frequency of cystoscopic evaluation. Markers must be validated by testing them prospectively using previously defined cut-off values. Furthermore, markers that will be used to alter treatment should be tested prospectively to determine the safety and cost-effectiveness of this strategy. Recommendations for future work include: (1) evaluation of markers in patients with dysplasia defined by the current pathologic classification; (2) evaluation of markers as indicators of tumor recurrence; (3) evaluation of markers as indicators of tumor progression; and (4) evaluation of markers in chemoprevention studies.

Telomere length and telomerase catalytic subunit expression in non-astrocytic gliomas

Telomerase activation has been implicated as a major factor in the development of cancer. In our previous study we reported on the telomerase activity of a variety of gliomas. To further investigate the role of telomere and telomerase regulation in the pathogenesis of non-astrocytic gliomas, we examined the telomere length and the mRNA expression of telomerase reverse transcriptase gene (hTERT) and telomerase-associated protein (hTEP) in a series of 27 oligodendroglial and 18 ependymal tumors in this study. No statistical difference was found between the mean telomere length in telomerase-positive and telomerase-negative tumors (11.5 kb vs 13.1 kb; p = 0.424), although a slightly shorter length was observed in telomerase-positive oligodendroglial tumors. mRNA expression of hTERT was highly correlated with the telomerase activity status. hTERT was expressed in 8/8 (100%) and 2/2 (100%) telomerase-positive oligodendroglial and ependymal tumors, respectively, whereas 3/6 (50%) telomerase-negative oligodendroglial tumors and no telomerase-negative ependymal tumors showed expression. In contrast, hTEP1 mRNA was widely expressed in both telomerase-positive and telomerase-negative oligodendroglial and ependymal tumors. Our data support the notion that hTERT plays a critical role in determining the enzymatic activity of human telomerase. It has recently been proposed that both p16(INK4)/Rb pathway inactivation and telomerase activity were required for immortalization of epithelial cells. Although lack of p(16INK4a) expression was detected in a substantial proportion of tumors, no correlation between the p16(INK4a) or pRb protein expression and telomerase activity was observed in our series of non-astrocytic tumors.

A critical analysis of the use of p53 as a marker for management of bladder cancer

Delineating the important molecular pathways in carcinogenesis has helped develop and advance the field of molecular diagnosis. Bladder cancer has served as an excellent model in translating some of the advances from the laboratory to clinical settings. Many investigators have examined the use of p53 to help manage patients with bladder cancer who are at high risk of tumor progression. This article reviews the clinical studies that have used p53 as a marker in bladder carcinoma and concludes by determining whether routine assessment of the p53 tumor suppressor gene/protein is indicated at this time.

Markers for recurrence of superficial bladder cancer: what is valid?

The management of superficial bladder cancer is characterized by early recognition of recurrences and the prevention of progression. Several clinical markers are used to divide patients into risk groups determining treatment and follow-up schemes. Although only a small fraction of patients will progress to invasive disease, survival of these patients is largely dictated by their bladder cancer. Whether early aggressive treatment of 'high-risk' superficial bladder cancer improves survival is not the issue of this article. Here we discuss the markers available for predicting tumour recurrence and progression. Clinical markers remain the most practical in decision-making and can identify high-risk patients. Molecular markers may be useful, but as yet insufficient evidence exists on their efficacy for daily use.