Performance of VI-RADS in predicting muscle-invasive bladder cancer after transurethral resection: a single center retrospective analysis

PURPOSE

To assess VIRADS performance and inter-reader agreement for detecting muscle-invasive bladder cancer (MIBC) following transurethral resection of bladder tumor (TURBT).

METHODS

An IRB-approved, HIPAA-compliant, retrospective study from 2016 to 2020 included patients with bladder urothelial carcinoma who underwent MRI after TURBT, and cystectomy within 3 months without post-MRI treatments. Three radiologists blinded to pathology results independently reviewed MR images and assigned a VI-RADS score. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of VI-RADS were assessed for diagnosing MIBC using VI-RADS scores ≥ 3 and ≥ 4. Inter-reader agreement was assessed using Gwet's agreement coefficient (AC) and percent agreement.

RESULTS

The cohort consisted of 70 patients (mean age, 68 years ± 11 [SD]; range 39-85; 58 men) and included 32/70 (46%) with MIBC at cystectomy. ROC analysis revealed an AUC ranging from 0.67 to 0.77 and no pairwise statistical difference between readers (p-values, 0.06, 0.08, 0.97). Percent sensitivity, specificity, PPV, NPV and accuracy for diagnosing MIBC for the three readers ranged from 81.3-93.8, 36.8-55.3, 55.6-60.5, 77.3-87.5, and 62.9-67.1 respectively for VI-RADS score ≥ 3, and 78.1-81.3, 47.4-68.4, 55.6-67.6, 72.0-78.8 and 61.4-72.9 respectively for VI-RADS score ≥ 4. Gwet's AC was 0.63 [95% confidence interval (CI): 0.49,0.78] for VI-RADS score ≥ 3 with 79% agreement [95% CI 72,87] and 0.54 [95%CI 0.38,0.70] for VI-RADS score ≥ 4 with 76% agreement [95% CI 69,84]. VIRADS performance was not statistically different among 31/70 (44%) patients who received treatments prior to MRI (p ≥ 0.16).

CONCLUSION

VI-RADS had moderate sensitivity and accuracy but low specificity for detection of MIBC following TURBT, with moderate inter-reader agreement.

Clinicopathological patterns of bladder carcinoma over 1 year: experience from University Hospital of Nepal

PURPOSE

To define the clinical and pathological patterns of urinary bladder carcinoma from the University Hospital of Nepal.

METHODS

This is a retrospective analytical study. Patients with bladder mass who underwent surgery over 1 year and who had data record were included in the study. Demographic profile, type of surgery, findings on clinical examination, cystoscopy findings, histopathological report, tumor stage, and post-surgery adjuvant therapy were analyzed.

RESULTS

Out of 86 patients who underwent transurethral resection of bladder tumor, 77 patients had biopsy-proven malignant bladder tumor. Urothelial cancer was present in 96.1%. Male were 78.6%. The mean age of diagnosis was 65.5 ± 11.8 years. Non-muscle-invasive bladder cancer (NMIBC) was 3.7 times more common than muscle-invasive bladder cancer (MIBC). High-grade tumors (58.6%) were more common than low grade (41.4%). The detrusor muscle was present inthe biopsy specimen of 48 patients (64%). Re-TURBT within 2-6 weeks was considered based on histopathology reports for about half of the patients (45.3%). Upstaging and upgrading of the tumor was present in 5.8 and 5.8% of the patients, respectively. Residual tumor without upstaging and upgrading was present in 23.5%. One patient (1.3%) had Clavien-Dindo grade 1, three (4%) patients had grade 2 and two patients (2.7%) had grade 3b.

CONCLUSION

In the present study, patients with bladder cancer are younger than reported in other studies. Smokers are strongly predisposed. The histological pattern is similar to the Western and Asian populations. NMIBC and MIBC occur in proportion to that described as in other studies. We had a lower rate of recurrence, upstaging and upgrading. We had a lesser rate of acceptance for radical cystectomy in our patients.

Ghrelin after chemotherapy as a prognostic predictor of progression-free survival in patients with muscle-invasive bladder cancer

Background

Although the patients with muscle-invasive bladder cancer (MIBC) generally have poor prognosis, the utility of these biomarkers for the prediction of oncological outcomes in MIBC has not been completely explored. Ghrelin regulates processes associated with cancer, including cell proliferation, apoptosis, cell migration, cell invasion, and angiogenesis. Thus, we aimed to evaluate the impact of serum ghrelin levels on survival in MIBC.

Methods

In this study, we reviewed the clinical and pathological records of 56 patients who were diagnosed with MIBC between November 2015 and November 2019 at Gifu and Hirosaki University Hospitals. We focused on 27 patients who had received chemotherapy and collected blood samples before and after chemotherapy. Blood samples were collected before chemotherapy and after completing two cycles of chemotherapy. Serum acyl (AG) and desacyl ghrelin (DG) were measured using AG and DG enzyme-linked immunosorbent assay kits (SCETI, Tokyo, Japan), respectively.

Results

The 3-year overall and progression-free survival (PFS) rates were 82.9% and 68.3%, respectively. According to the AG level after chemotherapy, the 3-year PFS rates were 77.5% and 53.0% in patients with AG levels ≥1.34 and <1.34 pg/mL, respectively (P=0.038). With regard to DG levels after chemotherapy, the 3-year PFS rates were 90.9% and 43.3% in patients with DG levels <92.3 and ≥92.3 pg/mL, respectively (P=0.039). On multivariate analysis, serum AG levels were significantly associated with PFS.

Conclusions

This study suggested the usefulness of the ghrelin as a prognostic predictor of PFS in patients with MIBC.

Population-based outcome of muscle-invasive bladder cancer following radical cystectomy: who can benefit from adjuvant chemotherapy?

Background

The benefit of adjuvant chemotherapy remains controversial in muscle-invasive bladder cancer (MIBC) after radical cystectomy. The present study’s primary objective was to construct a predictive tool for the reasonable application of adjuvant chemotherapy.

Methods

All of the patients analyzed in the present study were recruited from the Surveillance Epidemiology and End Results program between 2004 and 2015. Propensity score matching (PSM) was used to reduce inherent selection bias. Cox proportional hazards models were applied to identify the independent prognostic factors of overall survival (OS) and cancer-specific survival (CSS), which were further used to construct prognostic nomogram and risk stratification systems to predict survival outcomes. The prognostic nomogram’s performance was assessed by concordance index (C-index), receiver-operating characteristic (ROC) and calibration curves. Decision curve analysis (DCA) was performed to evaluate the clinical net benefit of the prognostic nomogram.

Results

A total of 6,384 patients with or without adjuvant chemotherapy were included after PSM. Several independent predictors for OS and CSS were identified and further applied to establish a nomogram for 3-, 5- and 10-year, respectively. The nomogram showed favorable discriminative ability for the prediction of OS and CSS, with a C-index of 0.709 [95% confidence interval (CI): 0.699–0.719] for OS and 0.728 (95% CI: 0.718–0.738) for CSS. ROC and calibration curves showed satisfactory consistency. The DCA revealed high clinical positive net benefits of the prognostic nomogram. The different risk stratification systems showed that adjuvant chemotherapy resulted in better OS (P<0.001) and CSS (P<0.001) than without adjuvant chemotherapy for high-risk patients; while the OS (P=0.350) and CSS (P=0.260) for low-risk patients were comparable.

Conclusions

We have constructed a predictive model and different risk stratifications for selecting a population that could benefit from postoperative adjuvant chemotherapy. Adjuvant chemotherapy was found to be beneficial for high-risk patients, while low-risk patients should be carefully monitored.

Systematic analysis of gene expression profiles reveals prognostic stratification and underlying mechanisms for muscle-invasive bladder cancer

Background

Muscle-invasive bladder cancer (MIBC) is originated in the muscle wall of the bladder, and is the ninth most common malignancy worldwide. However, there are no reliable, accurate and robust gene signatures for MIBC prognosis prediction, which is of the importance in assisting oncologists to make a more accurate evaluation in clinical practice.

Methods

This study used univariable and multivariable Cox regression models to select gene signatures and build risk prediction model, respectively. The t-test and fold change methods were used to perform the differential expression analysis. The hypergeometric test was used to test the enrichment of the differentially expressed genes in GO terms or KEGG pathways.

Results

In the present study, we identified three prognostic genes, KLK6, TNS1, and TRIM56, as the best subset of genes for muscle-invasive bladder cancer (MIBC) risk prediction. The validation of this stratification method on two datasets demonstrated that the stratified patients exhibited significant difference in overall survival, and our stratification was superior to three other stratifications. Consistently, the high-risk group exhibited worse prognosis than low-risk group in samples with and without lymph node metastasis, distant metastasis, and radiation treatment. Moreover, the upregulated genes in high-risk MIBC were significantly enriched in several cancer-related pathways. Notably, PDGFRB, a receptor for platelet-derived growth factor of PI3K-Akt signaling pathway, and TUBA1A were identified as two targets of multiple drugs. In addition, the angiogenesis-related genes, as well as two marker genes of M2 macrophage, CD163 and MRC1, were highly upregulated in high-risk MIBC.

Conclusions

In summary, this study investigated the underlying molecular mechanism and potential therapeutic targets associated with worse prognosis of high-risk MIBC, which could improve our understanding of progression of MIBC and provide new therapeutic strategies for the MIBC patients.

Transactivation of PTGS2 by PAX5 signaling potentiates cisplatin resistance in muscle-invasive bladder cancer cells

Cisplatin (CDDP)-based systematic chemotherapy remains the mainstay of treatment for muscle-invasive bladder cancer (MIBC). However, acquired resistance to CDDP, a multifactorial process governed by an array of signals acting at different levels, is the major problem in BC treatment. Here, we report for the first time that, expression of Paired-box gene 5 (PAX5), a B-cell essential transcription factor, was significantly induced in CDDP-resistant BC tissues and in experimentally-induced CDDP-resistant BC cells. Inhibition of PAX5 expression by shRNA treatment effectively improved CDDP sensitivity in BC cells, whereas overexpression of PAX5 potentiated CDDP resistance through supporting BC cell survival. Mechanistically, using luciferase reporter and chromatin immunoprecipitation assays, we identified prostaglandin-endoperoxide synthase 2 (PTGS2, also called COX2), a potent enzyme responsible for prostanoids formation and inflammatory response, as the direct down-stream target of PAX5. PAX5 exerted its oncogenic function during the pathogenesis of CDDP resistance via stimulation of PTGS2 transcription. These observations collectively suggest that dysregulation of PAX5/PTGS2 cascade plays a causal role in the induction of CDDP resistance and gene silencing approaches targeting this pathway may therefore provide a novel therapeutic strategy for overcoming CDDP resistance in BC.