What’s New in the Classification of Bladder Neuroendocrine Tumors?   I am delighted to share our comprehensive review article published this week in Endocrine Pathology @EndoPath, written by Dr. Anandi Lobo@loboAnandi   Our review provides an updated overview of neuroendocrine neoplasms of the urinary bladder, including small cell and large cell neuroendocrine carcinoma, mixed neuroendocrine neoplasms, well-differentiated neuroendocrine tumors, and paraganglioma. It highlights their distinctive histologic and immunophenotypic features, diagnostic pitfalls, clinical behavior, and emerging molecular biology. Emerging molecular data suggest that morphology alone may not fully capture their biological complexity. Most bladder neuroendocrine carcinomas are highly aggressive and frequently show TP53/RB1 inactivation, TERT promoter mutations, APOBEC-related changes, and lineage plasticity. Emerging transcriptomic subtypes defined by ASCL1, NEUROD1, and POU2F3 may have prognostic and therapeutic relevance. In this review, we also propose a more refined, bladder-specific classification framework that integrates histopathology, biomarkers, and molecular features.   Some key highlights: •TP53 and RB1 co-inactivation is a molecular hallmark of bladder neuroendocrine carcinoma, accompanied by frequent TERT promoter alterations and evidence of lineage plasticity. •Transcriptomic studies are identifying lineage-associated subgroups characterized by ASCL1, NEUROD1, and POU2F3, with potential prognostic and therapeutic relevance. •Recognition and quantification of mixed neuroendocrine–non-neuroendocrine components remain important for diagnosis and management. •We discuss a more refined, bladder-specific classification framework integrating morphology, proliferative activity, and molecular alterations, with the goal of improving diagnostic reproducibility and facilitating biomarker-driven therapy.   Full article is available: rdcu.be/fBUSt link.springer.com/article/10…