Evolving concepts and use of immunohistochemical biomarkers in flat non-neoplastic urothelial lesions: WHO 2016 classification update with diagnostic algorithm

HER2 Expression in Bladder Cancer: A Focused View on Its Diagnostic, Prognostic, and Predictive Role

Bladder cancer (BC) is a heterogeneous disease from a molecular, morphological, and clinical standpoint. HER2 is a known oncogene involved in bladder carcinogenesis. Assessing HER2 overexpression as a result of its molecular changes in a routine pathology practice using immunohistochemistry might be a useful adjunct in several scenarios, namely (1) to correctly identify flat urothelial lesions and inverted urothelial lesions in the diagnostic setting; (2) to provide prognostic hints in both non-muscle invasive (NMI) and muscle invasive (MI) tumors, thus supplementing risk stratification tools, especially when evaluating higher-risk tumors such as those with variant morphology; (3) to improve antibody panels as a surrogate marker of BC molecular subtyping. Furthermore, the potential of HER2 as a therapeutic target has been only partly explored so far, in light of the ongoing development of novel target therapies.

Are We Ready to Implement Molecular Subtyping of Bladder Cancer in Clinical Practice? Part 1: General Issues and Marker Expression

Bladder cancer (BC) is a heterogeneous disease with highly variable clinical and pathological features, and resulting in different outcomes. Such heterogeneity ensues from distinct pathogenetic mechanisms and may consistently affect treatment responses in single patients. Thus, over the last few years, several groups have developed molecular classification schemes for BC, mainly based on their mRNA expression profiles. A “consensus” classification has recently been proposed to combine the published systems, agreeing on a six-cluster scheme with distinct prognostic and predictive features. In order to implement molecular subtyping as a risk-stratification tool in routine practice, immunohistochemistry (IHC) has been explored as a readily accessible, relatively inexpensive, standardized surrogate method, achieving promising results in different clinical settings. The first part of this review deals with the steps resulting in the development of a molecular subtyping of BC, its prognostic and predictive implications, and the main features of immunohistochemical markers used as surrogates to stratify BC into pre-defined molecular clusters.

The impact of age on intravesical instillation of Bacille Calmette-Guerin treatment in patients with high-grade T1 bladder cancer

Intravesical instillation of Bacille Calmette-Guèrin (BCG) is the standard adjuvant treatment for high-risk non muscle invasive bladder cancer (NMIBC). Since its mechanism of action is supposed to be linked to the immune system efficiency and senescence could negatively affect this efficiency, BCG efficacy in the elderly has been questioned. This study aimed to assess the impact of age on BCG efficacy and safety in patients with high-grade T1 bladder cancer (BC).Among 123 patients with high-grade T1 BCG scheduled for BCG treatment, 82 were <75 year-old (group A) and 41 were ≥75 year-old (group B). Follow-up: urine cytology and cystoscopy every 3 months for the first 2 years, every 6 months for the third year, and then yearly. Tumor recurrence was defined as pathological evidence of disease at the bladder biopsy; tumor progression was defined as pathological shift to muscle invasive disease at the bladder biopsy or the imaging techniques showing recurrent BC and distant metastasis likely related to it.The median follow-up was 65 months (range 11-152). Recurrence occurred in 35 patients, 19 (23.2%) in the group A and 16 (39%) in the group B. Progression occurred in 18 patients, 12 (14.6%) in the group A and 6 (14.6%) in the group B. Recurrence free rate was similar in both groups up to 2 years. The 5 years progression rate was almost the same in both groups A and B (85.9% vs 84.7%), whereas the 5 years cancer-specific survival (CSS) was 92.6% in the group A and 85.4% in the group B. Of the 18 patients with progression, 11 underwent cystectomy; 12 patients died because of their BC. Kaplan-Meier plots pointed out no difference in recurrence-free, progression-free, and CSS between the 2 groups. Adverse events were similar in the 2 groups. Only 4 (3.3%) patients, 2 (2.4%) in the group A and 2 (4.8%) in the group B, experienced mild adverse reactions compatible with treatment.Elderly patients with high-grade T1 BC are not poorer candidates to BCG treatment, as they had similar benefit and adverse reactions than those aging ≥75 years.

Diagnostic and prognostic roles of CK20 in the pathology of urothelial lesions. A systematic review

Cytokeratin 20 (CK20) is one of the most common immunohistochemical markers in the routine practice of a pathology lab, as biopsies from the urinary tract encompass a wide spectrum of lesions which may pose issues in their detection and classification. In this review, we aim to outline the diagnostic accuracy and prognostic value of CK20 in flat urothelial lesions, papillary non-invasive and invasive urothelial carcinoma, molecular subgroups and variant histology, and we briefly discuss its limitations and potential pitfalls.

DHCR24 predicts poor clinicopathological features of patients with bladder cancer: A STROBE-compliant study

To investigate the prognostic value of DHCR24 for patients with bladder cancer (BC). We used public bladder cancer microarray studies to evaluate the expression of DHCR24 between normal bladder tissues and BC cells, to investigate the relationship between the expression of DHCR24 and the clinical features of BC patients. Survival analysis was performed to investigate the correlation between DHCR24 expression and the survivals of BC patients. Gene set enrichment analysis was conducted to identify relevant mechanisms. The results showed that DHCR24 was up-regulated in BC cells compared with that in normal bladder tissues (P = .0389). Results of chi-square test suggested that BC patients in DHCR24 low expression group were proved to have better clinical characteristics (including tumor grade, disease progression, T staging, and N staging) as compared with those in DHCR24 low expression group (P < .0001, P = .002, P = .005, and P = .002, respectively). BC patients in DHCR24 low expression group were associated with better cancer-specific survival and overall survival (P < .0001 and P = .0008, respectively). DHCR24 might promote the proliferation of BC cells through several oncogenesis-associated biological processes (estrogen response, heme metabolism, P53 pathway, cholesterol homeostasis, mTORC1 signaling, peroxisome, xenobiotic metabolism, glycolysis, and protein secretion). Thus, DHCR24 might be a therapeutic target for patients with BC.