# Aggressive high-grade urothelial carcinoma transforming into enteric-type adenocarcinoma: a case report

## TL;DR

A rare case of aggressive bladder cancer transforming into enteric-type adenocarcinoma is reported, highlighting the need for multimodal treatment strategies.

## Contribution

This case report presents a rare histological transformation in bladder cancer and emphasizes the importance of individualized treatment.

## Key findings

- The tumor progressed despite multiple chemotherapy cycles and transformed into enteric-type adenocarcinoma.
- Radical surgery and adjuvant radiotherapy were performed due to extensive tumor invasion.
- No lymph node metastases were found, but perineural and lymphovascular invasion was confirmed.

## Abstract

Bladder cancer, a malignancy with high morbidity and mortality, predominantly affects older adults, with urothelial carcinoma as the most common histological type. However, enteric-type adenocarcinoma arising from high-grade urothelial carcinoma is an exceptionally rare and aggressive variant.

This report details the case of a 44-year-old woman diagnosed at Rural Hospital. She presented with hematuria and frequent micturition, leading to a diagnosis of high-grade urothelial carcinoma with villoglandular differentiation. Despite multiple chemotherapy cycles (Gemcitabine-Carboplatin, followed by MVAC), the tumor progressed. Imaging revealed extensive invasion, necessitating radical anterior exenteration, including cystectomy, hysterectomy, and ileal conduit construction. Histopathology confirmed transformation into enteric-type adenocarcinoma with perineural and lymphovascular invasion but no lymph node metastases. Adjuvant radiotherapy was administered to mitigate recurrence risk.

This case underscores the complexities of managing aggressive bladder carcinoma with histological transformation and highlights the need for a multimodal treatment strategy. Individualized approaches integrating surgery, chemotherapy, and radiotherapy are crucial. Further research is needed to establish standardized protocols and identify biomarkers for early detection and targeted therapy.