The ancillary role of D2-40 in demonstration of muscularis propria invasion vs desmoplastic reaction in invasive urothelial carcinoma of the bladder

Key Points

• To evaluate the effectiveness of D2-40 and smooth muscle markers in differentiating muscularis propria invasion from desmoplastic reactions in bladder cancer.
• Immunohistochemical panel using D2-40 and smooth muscle markers (desmin or H-caldesmon)
• Assessment of bladder carcinoma samples with equivocal morphology
• D2-40 and smooth muscle markers effectively distinguished muscularis propria invasion from desmoplastic reaction
• Improved diagnostic accuracy when morphology was unclear