Pathology

Papillary urothelial carcinoma

Squamous cell carcinoma

• A thick papilla with a fibrovascular core

• CIS: focal or diffuse erythematous, flat, velvety lesion(s) in the bladder mucosa

• Low-grade tumors: usually pedunculated with a papillary surface; and noninvasive

• High-grade tumors: usually sessile and nodular/solid; and invasive (invading lamina propria or deeper tissues)

• Chronic inflammatory stimuli (e.g., schistosomiasis, chronic cystitis) can lead to transformation of urothelial cells into squamous epithelial cells (squamous metaplasia)

• Squamous epithelial cells that are constantly exposed to urine are prone to dysplasia and squamous cell carcinoma