Myofibroblasts reaction in urothelial carcinomas

Area of Science:

• Oncology
• Pathology
• Urology

Background:

• Myofibroblasts are connective tissue cells with uncertain origins, exhibiting fibroblast and smooth muscle cell characteristics.
• They are typically found in limited organs but increase in malignancies, particularly in breast carcinomas.
• Data on myofibroblast presence and behavior in urothelial carcinomas is scarce.

Purpose of the Study:

• To investigate the presence and immunophenotype of myofibroblasts in urothelial carcinoma specimens.
• To correlate myofibroblast presence with tumor stage and differentiation grade.

Main Methods:

• Histopathological analysis of 59 urothelial carcinoma specimens using HE staining.
• Immunohistochemical staining for smooth muscle actin, vimentin, and desmin to detect myofibroblasts.
• Examination of normal bladder tissue and various tumor stages (Ta, T1, T2, T3) and differentiation grades (G3).

Main Results:

• No myofibroblast morphology or immunophenotype was observed in normal bladder tissue or Ta-stage urothelial carcinomas.
• Myofibroblasts were identified in 26.92% of T1-stage tumors.
• The number of myofibroblasts varied in T2 and T3 stage tumors, being significantly higher in high-grade (G3) tumors.

Conclusions:

• Myofibroblasts are not present in normal urothelium or early-stage urothelial carcinomas (Ta).
• Myofibroblast presence is associated with advanced stages (T1-T3) of urothelial carcinoma.
• A higher prevalence of myofibroblasts correlates with higher tumor differentiation grades (G3) in advanced stages.