Prognostic value of histopathological tumour growth patterns at the invasion front of T1G3 urothelial carcinoma of the bladder

A novel grading approach predicts worse outcomes in stage pT1 non-muscle-invasive bladder cancer

OBJECTIVE

To develop a prognostically relevant scoring system for stage pT1 non-muscle-invasive bladder cancer (NMIBC) incorporating tumour budding, growth pattern and invasion pattern because the World Health Organisation grading system shows limited prognostic value in such patients.

PATIENTS AND METHODS

The tissue specimens and clinical data of 113 patients with stage pT1 NMIBC who underwent transurethral resection of bladder tumour were retrospectively investigated. Tumour budding, and growth and invasion patterns were evaluated and categorised into two grade groups (GGs). GGs and other clinical and histopathological variables were investigated regarding recurrence-free survival (RFS), progression-free survival (PFS), cancer-specific survival (CSS) and overall survival (OS) using univariable and multivariable Cox regression analyses.

RESULTS

The integration of two tumour budding groups, two growth patterns, and two invasion patterns yielded an unfavourable GG (n = 28; 24.7%) that had a high impact on oncological outcomes. The unfavourable GG was identified as an independent RFS and OS predictor (P = 0.004 and P = 0.046, respectively) and linked to worse PFS (P = 0.001) and CSS (P = 0.001), irrespective of the European Association of Urology risk group. The unfavourable GG was associated with higher rates of BCG-unresponsive tumours (P = 0.006). Study limitations include the retrospective, single-centre design, diverse therapies and small cohort.

CONCLUSIONS

We present a morphology-based grading system for stage pT1 NMIBC that correlates with disease aggressiveness and oncological patient outcomes. It therefore identifies a highest risk group of stage pT1 NMIBC patients, who should be followed up more intensively or receive immediate radical cystectomy. The grading incorporates objective variables assessable on haematoxylin and eosin slides and immunohistochemistry, enabling an easy-to-use low-cost approach that is applicable in daily routine. Further studies are needed to validate and confirm these results.

Proposal for a Novel Histological Scoring System as a Potential Grading Approach for Muscle-invasive Urothelial Bladder Cancer Correlating with Disease Aggressiveness and Patient Outcomes

BACKGROUND

Grading of muscle-invasive bladder cancer (MIBC) according to the current World Health Organization (WHO) criteria is controversial due to its limited prognostic value. All MIBC cases except a tiny minority are of high grade.

OBJECTIVE

To develop a prognostic histological scoring system for MIBC integrating histomorphological phenotype, stromal tumor-infiltrating lymphocytes (sTILs), tumor budding, and growth and spreading patterns.

DESIGN, SETTING, AND PARTICIPANTS

Tissue specimens and clinical data of 484 patients receiving cystectomy and lymphadenectomy with curative intent with or without adjuvant chemotherapy. Histomorphological phenotypes, sTILs, tumor budding, and growth and spreading patterns were evaluated and categorized into four grade groups (GGs). GGs were correlated with molecular subtypes, immune infiltration, immune checkpoint expression, extracellular matrix (ECM) remodeling, and epithelial-mesenchymal transition (EMT) activity.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

GGs were associated with overall (OS), disease-specific (DSS), and progression-free (PFS) survival in univariable and multivariable analyses. Association with biological features was analyzed with descriptive statistics.

RESULTS AND LIMITATIONS

Integration of two histomorphological tumor groups, three sTILs groups, three tumor budding groups, and four growth/spread patterns yielded four novel GGs that had high significance in the univariable survival analysis (OS, DSS, and PFS). GGs were confirmed as independent prognostic predictors with the greatest effect in the multivariable Cox regression analysis. Correlation with molecular data showed a gradual transition from basal to luminal subtypes from GG1 to GG4; a gradual decrease in survival, immune infiltration, and immune checkpoint activity; and a gradual increase in ECM remodeling and EMT activity.

CONCLUSIONS

We propose a novel, prognostically relevant, and biologically based scoring system for MIBC in cystectomies applicable to routine pathological sections.

PATIENT SUMMARY

We developed a novel approach to assess the aggressiveness of advanced bladder cancer, which allows improved risk stratification compared with the method currently proposed by the World Health Organization.

Association of current molecular subtypes in urothelial carcinoma with patterns of muscularis propria invasion

Urothelial carcinoma is subdivided into luminal (L), basal (B), and p53-wild-type (WT) molecular subtypes, with basal and p53-WT groups showing more aggressive course and poor treatment response, respectively. The literature on molecular subtypes of UC includes a mixture of different stages. We investigated the molecular profile and outcome of pure cohort of muscle invasive bladder carcinoma (MIBC) considering two distinct patterns of muscularis propria (MP) invasion. Forty-three cystectomies harboring stage pT2 were retrospectively identified in 18 years. MP invasion was subclassified into patterns 1 (tumor encasing intact detrusor muscle bundles) and 2 (tumor dissecting/replacing detrusor muscle). Using IHC, B/L phenotypes, p53, and Ki67 were assessed, and survival data was collected. Pattern 1 invasion was noted in 16 (37%) and pattern 2 in 27 (63%), with mean age of pattern 1 being 10 years younger. B/L phenotypes were successfully determined in 83.7%; 48.8% and 34.8% revealed L and B phenotypes, respectively (indeterminate phenotype in 16.4%). Pattern 1 was associated with L phenotype (GATA3 and HER-2 expressions: p = 0.02 & p = 0.04, respectively). Ki67 ≥ 5/10HPF was noted in pattern 2 and B phenotype (p = 0.03). B phenotype showed association with p53-WT (p = 0.007). In median follow-up of 60.7 months, 63.6% of pattern 1 cases were alive without disease compared to 32% of pattern 2 (not significant). A panel of CK20 and GATA3 for luminal and CK5/6 and CK14 for basal subtypes can provide reliable molecular classification in UC. Also, morphology of MIBC can predict the molecular phenotype and the behavior of the UC.

Prognostic Value of c-Myc Immunohistochemical Expression in Muscle Invasive Urothelial Carcinoma of the Urinary Bladder: A Retrospective Study

Objective:

This study aimed to investigate the immunohistochemical expression of c-Myc in muscle invasive urothelial carcinoma (MIUC) of the urinary bladder and to evaluate the correlation of c-Myc expression with different clinicopathological parameters and outcome, including a relatively new histopathological tumor characteristic that is the growth pattern of tumor invasion.

Methods:

A total of 66 formalin-fixed and paraffin-embedded sections of MIUC obtained from radical cystectomy specimens were enrolled. The sections were stained with c-Myc antibody using immunohistochemistry technique.

Results:

Tumor cells showed variability in nuclear c-Myc expression according to the growth pattern of invasion. The median H-score of nuclear expression of infiltrative pattern was significantly higher than that of non-infiltrative pattern (p<0.001). Nuclear expression of c-Myc in tumor tissue had a significant association with poor prognostic factors (sarcomatoid variant (p<0.001), perineural invasion (p=0.037), lymphovascular invasion (p<0.001), lymph node metastasis (p<0.001), distant metastasis (p=0.042) and advanced stage grouping (p=0.001). Kaplan Meier survival analysis demonstrated that c-Myc expression could not be significantly correlated with overall survival or disease free survival rates.

Conclusion:

Nuclear c-Myc seems to have a prominent role in epithelial to mesenchymal transition with consequential in tumor progression and metastasis, while it is not as much useful to predict the clinical behavior of patients with MIUC.

Concomitant carcinoma in situ may not be a prognostic factor for patients with bladder cancer following radical cystectomy: a PRISMA-compliant systematic review and meta-analysis

BACKGROUND

Numerous recent studies have shown that concomitant carcinoma in situ (CIS) can be closely associated with the prognosis of patients with bladder cancer (BCa). However, the prognostic value of CIS in BCa is still not conclusive. Hence, we performed a systematic review and meta-analysis to explore the association between CIS and clinicopathological features and the prognostic value for BCa following radical cystectomy.

METHODS

We performed this study in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Relevant studies were systematically collected from PubMed, EMBASE, and Web of Science, with an expiration date of August 2018. Hazard ratios and 95% confidence intervals (CIs) were pooled to assess the intensity of association. All data were analyzed by Stata 12.0. Moreover, heterogeneity and publication bias were determined, and sensitivity analysis was performed to examine whether the findings of the meta-analysis were robust.

RESULTS

A total of 18,845 patients from 24 studies were included in the analysis. Our results indicated that CIS has no significant correlation with cancer-specific mortality (CSM) (pooled HR = 0.97, 95% CI 0.93-1.00, p = 0.059), overall mortality (OM) (pooled HR = 0.93, 95% CI 0.85-1.01, p = 0.076), overall survival (OS) (pooled HR = 1.04, 95% CI 0.96-1.12, p = 0.386), cancer-specific survival (CSS) (pooled HR = 1.06, 95% CI 0.97-1.16, p = 0.186), recurrence-free survival (RFS) (HR = 1.05, 95% CI 0.99-1.11, p = 0.098) or recurrence (pooled HR = 1.04, 95% CI 0.98-1.11, p = 0.212) in BCa patients. In addition, CIS was not correlated with gender (male vs. female, OR = 1.00, 95% CI 0.74-1.34, p = 0.978), pathological stage (III/IV vs. I/II: OR = 0.74, 95% CI 0.50-1.10, p = 0.132), tumor grade (1/2 vs. 3: OR = 3.38, 95% CI 0.73-15.65, p = 0.119), soft tissue surgical margin (STSM) (+ vs. - : OR = 1.20, 95% CI 0.97-1.48, p = 0.093) or lymphovascular invasion (LVI) (+ vs. - : OR = 0.92, 95% CI 0.62-1.38, p = 0.702),but was closely related to adjuvant chemotherapy (ACT) (yes vs. no, OR = 1.17, 95% CI 1.03-1.32, p = 0.019). Furthermore, these findings were demonstrated to be reliable by our sensitivity and subgroup analysis.

CONCLUSIONS

The prognostic value of CIS in BCa remains inconclusive in patients submitted to RC. Our data indicated that CIS may have no significant correlation with the prognosis and clinicopathological parameters of BCa patients, and also may not be applied to risk stratification or individualized therapy in BCa patients. Further research should be conducted to confirm our findings.

High-grade ovarian serous carcinomas: Significant correlation of histologic patterns with IMP3 and E-Cadherin predicting disease recurrence and survival

Most high-grade serous carcinomas (HGSC) of the ovary are advanced stage tumors with early recurrences. However, some tumors do not recur and have a better survival. We identified such cases of HGSC and compared those with the cases that recurred and assessed the relationship between patterns of invasion (intracystic, IC; micropapillary, MP; nonpapillary, NP) with IMP3 and E-Cadherin expression, and evaluated their predictive role in recurrence and survival. The study comprised of seventeen tumors recurred within 18 months of follow-up and 14 cases that did not recur with a minimum follow-up of 49 months. 73% tumors with predominantly MP pattern recurred, while only 27% of non-recurrent tumors showed this pattern. In contrast, predominant NP and IC patterns were seen in 71% of the non-recurrent and in 35% of recurrent tumors. 67.7% tumors expressed IMP3 and all cases expressed E-Cadherin. The tumors with a higher percentage of destructive invasion showed higher IMP3 positivity and greater chances of recurrence, whereas tumors with higher percentage of pushing invasion showed lower IMP3 positivity and lesser chances of recurrence (p = 0.02). IMP3-negative tumors had lower odds of recurrence than IMP3-positive ones (p = 0.01). The patients with negative IMP3 staining had a significantly higher OS than those with IMP3 positive tumors (p = 0.01), regardless of the histologic patterns. Also, reduction in E-Cadherin staining in the metastatic site led to poor DFS (p = 0.016) and OS (p = 0.006). IMP3 may serve as a useful prognostic marker that can stratify patients of advanced stage, high-grade serous carcinomas into two distinct subsets: majority with early recurrence with an infiltrative pattern of invasion and IMP3 positivity particularly in the MP areas; and a smaller subset that do not show early recurrence having pushing borders and are IMP3 negative. Also, E-Cadherin showed significant decrease in expression in the metastatic site of the recurrent cases.

Prognostic significance of tumor budding in muscle invasive urothelial carcinomas of the bladder

OBJECTIVE

The aim of this study was to evaluate the prognostic significance of tumor budding in muscle invasive urothelial carcinoma of bladder (MIBC).

MATERIAL AND METHODS

A total of 60 patients who underwent radical cystectomy and cystoprostatectomy for MIBC were included in the study. The correlations between tumor budding, and tumor necrosis, lymphovascular invasion (LVI), perineural invasion (PNI) and histopathological data with distant metastasis were evaluated. The correlation between progression free (PFS) and overall survival (OS) rates and the presence, and grade of tumor budding was investigated.

RESULTS

A statistically significant correlation was not seen between tumor budding, necrosis, LVI, and PNI. There was a strong correlation between distant organ metastasis, and presence of tumor necrosis. There was no statistically significant correlation between PFS, OS and tumor budding. A statistically significant relationship was observed between OS and tumor stage, lymph node metastasis, and distant organ metastasis.

CONCLUSION

In our study, statistically significant effect of tumor budding on survival rates in MIBCs was not observed. Also, no significant correlation was observed between tumor budding and tumor necrosis, LVI, and PNI.

Collagen type IV alpha 1 (COL4A1) and collagen type XIII alpha 1 (COL13A1) produced in cancer cells promote tumor budding at the invasion front in human urothelial carcinoma of the bladder

Current knowledge of the molecular mechanism driving tumor budding is limited. Here, we focused on elucidating the detailed mechanism underlying tumor budding in urothelial cancer of the bladder. Invasive urothelial cancer was pathologically classified into three groups as follows: nodular, trabecular, and infiltrative (tumor budding). Pathohistological analysis of the orthotopic tumor model revealed that human urothelial cancer cell lines MGH-U3, UM-UC-14, and UM-UC-3 displayed typical nodular, trabecular, and infiltrative patterns, respectively. Based on the results of comprehensive gene expression analysis using microarray (25 K Human Oligo chip), we identified two collagens, COL4A1 and COL13A1, which may contribute to the formation of the infiltrative pattern. Visualization of protein interaction networks revealed that proteins associated with connective tissue disorders, epithelial-mesenchymal transition, growth hormone, and estrogen were pivotal factors in tumor cells. To evaluate the invasion pattern of tumor cells in vitro, 3-D collective cell invasion assay using Matrigel was performed. Invadopodial formation was evaluated using Gelatin Invadopodia Assay. Knockdown of collagens with siRNA led to dramatic changes in invasion patterns and a decrease in invasion capability through decreased invadopodia. The in vivo orthotopic experimental model of bladder tumors showed that intravesical treatment with siRNA targeting COL4A1 and COL13A1 inhibited the formation of the infiltrative pattern. COL4A1 and COL13A1 production by cancer cells plays a pivotal role in tumor invasion through the induction of tumor budding. Blocking of these collagens may be an attractive therapeutic approach for treatment of human urothelial cancer of the bladder.

Stalk versus base invasion in pT1 papillary cancers of the bladder: improved substaging system predicting the risk of progression

AIMS

Pathological stage pT1 bladder cancers constitute a clinically heterogeneous group. However, current staging guidelines for superficially invasive cancers do not acknowledge the variability in type and extent of lamina propria invasion in papillary urothelial carcinomas (PUCs), and historically proposed substaging systems showed either high interobserver variation or limited value in predicting patient outcomes. The aim of this study was to reappraise pT1 PUC substaging, with the objective of identifying a novel scheme that is reproducible and prognostically meaningful.

METHODS AND RESULTS

pT1 PUCs diagnosed during 1999-2015 were retrospectively reviewed and characterized as focal invasion confined to the papillary stalk, focal invasion of the tumour base, or extensive invasion of the tumour base. Cases with concurrent flat carcinoma in situ, angiolymphatic invasion, absent muscularis propria or clinically advanced disease were excluded. We calculated cumulative incidence rates of recurrence, progression and death by tumour subtype, and evaluated differential risks by using log-rank tests and Kaplan-Meier curves stratified by type and extent of invasion. Among 62 patients satisfying the inclusion criteria, 22 of 29 patients with base-extensive invasion progressed, whereas four of 13 with base-focal and none of 20 with stalk-only invasion progressed. There was strong evidence that base-extensive patients had a higher risk of progression and death resulting from bladder cancer than base-focal or stalk-only patients (P < 0.0001). However, tumour subtype was not significantly associated with risk of recurrence (P = 0.21).

CONCLUSIONS

We propose an innovative substaging approach for reporting the site and extent of lamina propria invasion in patients with pT1 PUC, allowing patient stratification for risk of progression.

WHO 1973 grade 3 and infiltrative growth pattern proved, aberrant E-cadherin expression tends to be of predictive value for progression in a series of stage T1 high-grade bladder cancer after organ-sparing approach

PURPOSE

Stage pT1 urothelial bladder cancer (UBC) is characterized as a challenging subentity of urothelial carcinoma with an unforeseeable clinical course. In addition to more or less established clinical and histopathological features, we evaluated the role of epithelial-mesenchymal transition (EMT) marker E-cadherin, shown to be of prognostic value in muscle-invasive disease, regarding the prognosis of stage pT1 high-grade (hg) UBC.

METHODS

Tissue of 226 stage pT1 hg UBC patients from transurethral resection could be immunostained for E-cadherin. Kaplan-Meier analysis and univariate and multivariate Cox regression analyses regarding progression-free (PFS) and cancer-specific survival (CSS) were performed.

RESULTS

Aberrant expression of E-cadherin was recognized in 74% of patients. Kaplan-Meier analysis showed that aberrant E-cadherin expression was associated with worse 10-year PFS (62 vs. 90%, p = 0.045). In univariate analysis, aberrant E-cadherin staining, associated carcinoma in situ, grading 3 after WHO classification 1973 and infiltrative growth pattern at the invasion front were the statistically significant predictive factors for worse PFS, only infiltrative growth pattern for CSS. With regard to progression, grading 3 after WHO classification of 1973 (HR 6.49; CI 1.54-27.28, p = 0.011) and infiltrative tumor invasion pattern (HR 2.06; CI 1.10-3.86, p = 0.024) revealed as independent factors for PFS, and there was a trend also for E-cadherin expression (HR 0.45; CI 0.19-1.06; p = 0.068). Regarding CSS, infiltrative tumor growth pattern (HR 3.79; CI 1.67-8.60, p = 0.001) was the only statistically significantly independent predictive factor in multivariate Cox regression analysis.

CONCLUSIONS

Beside invasion growth pattern and WHO grading 1973 that achieved to be independent prognostic factors, there was a trend for the parameter E-cadherin expression to be of predictive value for PFS in stage pT1 hg urothelial bladder carcinoma after organ-sparing approach. Further studies on genetic level are warranted to define the distinct role of EMT in early-invasive UBC.

Exploration of risk factors predicting outcomes for primary T1 high-grade bladder cancer and validation of the Spanish Urological Club for Oncological Treatment scoring model: Long-term follow-up experience at a single institute

OBJECTIVE

To determine the prognostic factors of primary T1 high-grade bladder cancer and to validate the Spanish Urological Club for Oncological Treatment model in Japanese patients with T1 high-grade bladder cancer treated at a single institution.

METHODS

Records of 106 patients with T1 high-grade bladder cancer treated from 1998 to 2013 were retrospectively reviewed. Variables included various clinicopathological parameters, including lymphovascular invasion and tumor growth pattern at the invasion front. Recurrence-free survival and progression-free survival were analyzed. Multivariate Cox proportional regression analysis was used to verify the prognostic significance of the variables. Scores for recurrence and progression were calculated using the Spanish Urological Club for Oncological Treatment model.

RESULTS

Of 106 patients, 44 (42%) had recurrence and 16 (15%) developed progression after a median (interquartile range) follow-up period of 54 months (range 32-81 months). Non-papillary shape was the only independent predictor for recurrence, while broad-based tumor stalk and infiltrative tumor growth pattern at the invasion front were determined to be independent predictors for progression. Stratification of patients according to the number of progression risk factors yielded hazard ratios of 10.1 and 13.1 in patients having one and two risks, respectively, compared with those without any risks. The Spanish Urological Club for Oncological Treatment model successfully stratified our patients with a trend toward different probabilities of recurrence and progression.

CONCLUSIONS

The results of the present study might be helpful for counseling certain patients towards intensive treatment, such as radical cystectomy and/or platinum-based systemic chemotherapy. In addition, the Spanish Urological Club for Oncological Treatment model might be applicable to Japanese patients with T1 high-grade bladder cancer.

[Non-muscle-invasive high-grade bladder cancer]

BACKGROUND

Non-muscle-invasive bladder cancer with a low-grade differentiation represents a special challenge.

METHOD

Although urine cytology is still the most reliable and effective urine-based marker and there are no substantial novel aspects in this field, photodynamic diagnostics have the most important value in transurethral resection of the bladder (TURB) of high-grade T1 tumors and new techniques, such as hybrid knife TURB are coming up. The histopathological assessment of T1 tumors can be supplemented by a description of the exact penetration depth, so-called substaging and the invasion pattern.

RESULTS

Intravesicle therapy with Bacillus Calmette-Guèrin (BCG) represents the gold standard and a pillar of bladder-preserving therapy and should be planned as maintenance therapy for at least 1 year. With the right risk constellation cystectomy is a safe and proven concept for high-grade bladder cancer, even without proof of muscle invasion.

Second transurethral resection and prognosis of high-grade non-muscle invasive bladder cancer in patients not receiving bacillus Calmette-Guérin

OBJECTIVE

To define the natural history of T1G3 bladder tumor not receiving intravesical Bacillus Calmette-Guerin (BCG) and assess the diagnostic and therapeutic value of a second transurethral resection (Re-TUR) in these patients.

PATIENTS AND METHODS

Retrospective study on the natural history of 210 patients treated at two institutions for T1G3 bladder carcinoma without associated CIS. In no case was BCG administered; 79 (37.6%) received TUR alone, and 131 (62.4%) Re-TUR 4 to 6 weeks later; 23 (12.4%) underwent cystectomy for tumor progression.

RESULTS

Median follow-up was 55 (78 IQR) months, male/female ratio 8/1, and mean age 70.6+11.8 (range 37-93). 19.5% were free of recurrence at 10 years, and 61.9% free of progression. Independent prognostic factors for progression were solid pattern (HR: 2.71; P=.0004), multiplicity (HR: 2.26; P=.003), and recurrence at 3 months (HR: 3.4; P=.003). Cancer-specific survival was 81.5% at 5 and 69% at 10 years. Independent predictors of survival were: progression during the first year (HR: 17.9; P<.0001), solid pattern (HR: 2.13; P=.02), multiplicity (HR: 2.05; P=.03), and age>65 years (HR: 2.9; P=.03). Re-TUR avoided under-staging (7.4%), detected T1G3 residual disease (10.7%), reduced recurrence rate at 3 months (11.4 to 4.6%; P=.06), and rate of progression on the 1st year (13.9 to 3.8%; P=.0075). However, in these patients the risk remains and no differences were detected in the long term in terms of recurrence (log-rank, P=.14), progression (P=.91), or cancer death (P=.21) in patients treated with Re-TUR.

CONCLUSION

The recurrence in the first 3 months of a T1G3 tumor not receiving BCG is the main risk factor for progression, and progression of this type of tumors within the first year is the main factor of cancer death. The Re-TUR improves both variables but it does not change the long-term prognosis.

Introduction and first clinical application of a simplified immunohistochemical validation system confirms prognostic impact of KI-67 and CK20 for stage T1 urothelial bladder carcinoma: single-center analysis of eight biomarkers in a series of three hundred six patients

BACKGROUND

Biomarkers could help to estimate the prognosis of solid tumors. One of the reasons that many immunohistochemical (IHC) markers are not used routinely is the high interobserver variability and various cutoff values. In the present study, we used a simplified IHC method with a group of 8 biomarkers in stage pT1 urothelial bladder carcinoma (UBC).

PATIENTS AND METHODS

IHC expression of CK20, KI-67, STK15, MUC7, periostin, fibronectin, survivin, and CXCR4 was assessed independently by 2 reviewers in a series of 306 stage pT1 UBC specimens from a single center in 10% steps from < 10% up to > 90%. A general center < 10% vs. ≥ 10% was set for further analysis for all markers. All patients initially underwent a bladder-sparing approach. Kaplan-Meier analyses and multivariate Cox regression analyses of recurrence-free survival (RFS), progression-free survival (PFS), and cancer-specific survival (CSS) were performed.

RESULTS

A cutoff point ≥ 10% was shown to be valid and reliable for marker expression, with 96% interobserver agreement. Of the studied marker expressions, ≥ 10% for Ki-67 showed a statistically significant worse RFS (54% vs. 64%; P = .004), PFS (66% vs. 73%; P = .001), and CSS (71% vs. 77%; P = .015); ≥ 10% for CK20 showed a worse RFS (57% vs. 58%; P = .009). Multivariate Cox regression analysis revealed CK20 to be an independent prognostic factor for recurrence (hazard ratio [HR], 2.08; confidence interval [95% CI]; 1.21-3.57; P = .008) and Ki-67 for progression (HR, 2.11; CI, 1.02-4.37; P = .045).

CONCLUSION

We proposed and applied a simplified IHC evaluation that increases interobserver agreement and confirms the prognostic role of Ki-67 and CK20 for stage T1 UBC.

Loss of aquaporin 3 protein expression constitutes an independent prognostic factor for progression-free survival: an immunohistochemical study on stage pT1 urothelial bladder cancer

BACKGROUND

Treatment of patients with stage pT1 urothelial bladder cancer (UBC) continues to be a challenge due to its unpredictable clinical course. Reliable molecular markers that help to determine appropriate individual treatment are still lacking. Loss of aquaporin (AQP) 3 protein expression has previously been shown in muscle-invasive UBC. The aim of the present study was to investigate the prognostic value of AQP3 protein expression with regard to the prognosis of stage pT1 UBC.

METHOD

AQP 3 protein expression was investigated by immunohistochemistry in specimens of 87 stage T1 UBC patients, who were diagnosed by transurethral resection of the bladder (TURB) and subsequent second resection at a high-volume urological centre between 2002 and 2009. Patients underwent adjuvant instillation therapy with Bacillus Calmette-Guérin (BCG). Loss of AQP3 protein expression was defined as complete absence of the protein within the whole tumour. Expression status was correlated retrospectively with clinicopathological and follow-up data (median: 31 months). Multivariate Cox regression analysis was used to assess the value of AQP3 tumour expression with regard to recurrence-free (RFS), progression-free (PFS) and cancer-specific survival (CSS). RFS, PFS and CSS were calculated by Kaplan-Meier analysis and Log rank test.

RESULTS

59% of patients were shown to exhibit AQP3-positive tumours, whereas 41% of tumours did not express the marker. Loss of AQP3 protein expression was associated with a statistically significantly worse PFS (20% vs. 72%, p=0.020). This finding was confirmed by multivariate Cox regression analysis (HR 7.58, CI 1.29 - 44.68; p=0.025).

CONCLUSIONS

Loss of AQP3 protein expression in pT1 UBC appears to play a key role in disease progression and is associated with worse PFS. Considering its potential prognostic value, assessment of AQP3 protein expression could be used to help stratify the behavior of patients with pT1 UBC.

Clinical significance of subepithelial growth patterns in non-muscle invasive bladder cancer

BACKGROUND

We evaluated the clinical significance and prognostic value of histopathological features of bladder cancer, such as subepithelial growth patterns and tumor growth pattern at the invasion front.

METHODS

In total, 130 patients newly diagnosed with non-muscle invasive bladder cancer and underwent transurethral resection between 1998 and 2009 were enrolled. Subepithelial growth patterns consisting of endophytic growth pattern (EGP) and von Brunn's nest involvement (VBNI) were investigated using hematoxylin and eosin-stained slides, and their frequency of occurrence, prognostic value, and correlation with other clinicopathological features was evaluated.

RESULTS

EGP and VBNI were found in 40 (30.8%) and 5 (3.9%) of the 130 cases, respectively. Of the 26 pT1 tumors, the growth pattern at the invasion front was trabecular in 17 (65.4%) and infiltrative in 9 (34.6%). Although 8 (47.1%) of 17 trabecular tumors coexisted with EGP, no cases with infiltrative tumors had EGP (p = 0.023). VBNI correlated with high tumor grades (p = 0.006) and lymphovascular involvement (p = 0.026). The multivariate Cox proportional hazards analysis revealed that tumor diameter less than 3 cm (p = 0.04) and intravesical bacillus Calmette-Guérin therapy (p = 0.004) were independent favorable prognostic factors for recurrence-free survival, whereas tumor stage was an independent poor prognostic factor for disease progression (p = 0.006).

CONCLUSIONS

Subepithelial growth patterns were not a significant prognostic factor in this study. Additionally, no tumors with an infiltrative growth pattern coexisted with EGP, suggesting that determining the presence of EGP might be helpful for managing non-muscle invasive bladder cancers.