Genomic Profiling and Immune Phenotyping of Neuroendocrine Bladder Cancer - Expert Commentary

Neuroendocrine bladder cancer (NEBC) is a rare, aggressive urinary tract malignancy with poor prognosis and limited treatment options. A recent study by Zang et al. in Clinical Cancer Research characterized the immunogenomic landscape of NEBC to explore immunotherapy as a potential treatment approach.

The researchers analyzed 35 NEBC cases through genomic analysis of 19 samples, transcriptomic analysis of 3 samples, single-cell RNA sequencing of 1 sample, and IHC analyses of 34 samples. Their findings revealed that despite a high mutational burden, NEBC showed immunologically inactive profiles. Unexpectedly, most tumors displayed either "immune-excluded" (41.2%) or "immune-desert" (26.5%) phenotypes, while mixed NEBC with concurrent urothelial bladder cancer showed an "immune-infiltrated" phenotype (32.3%) with better prognosis.

As a potential explanation, NEBC demonstrated denser cellular composition and enhanced peritumoral extracellular matrix compared to urothelial bladder cancer. Single-agent immune checkpoint inhibitors showed limited efficacy, while combination chemoimmunotherapy demonstrated improved response rates.

This study provides critical insights into NEBC immune biology. It suggests that combination chemoimmunotherapy is a promising therapeutic strategy warranting further investigation through prospective trials for patients with this aggressive disease.

Written by: Bishoy M. Faltas, MD, Director of Bladder Cancer Research, Englander Institute for Precision Medicine, Weill Cornell Medicine

Reference:

  1. Zang J, Shahatiaili A, Cai M-C, et al. Genomic Profiling and Immune Phenotyping of Neuroendocrine Bladder Cancer. Clin Cancer Res. 2024;30(21):4920-4931. doi:10.1158/1078-0432.CCR-24-1277
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