Adenocarcinoma of the bladder
Adenocarcinoma of the bladder accounts for 0.5–2 of bladder tumours. Risk factors include bladder exstrophy, bladder augmentation, schistosomiasis, and endometriosis. Bladder adenocarcinoma is classified as primary, arising from the bladder or urachal remnant, and secondary (metastatic). Most patients present with haematuria and irritative voiding symptoms. On imaging, a typical lesion is commonly located at the bladder dome. Compared to urothelial carcinoma (UC), most adenocarcinomas are diagnosed at high grade and advanced stage. Surgical treatment of localized disease entails partial cystectomy for urachal tumours and radical cystectomy for non-urachal or large urachal adenocarcinoma. The optimal treatment for metastatic disease has yet to be defined. Overall survival rates are 20–70% at 5 years, similar to those for UC, when adjusted for stage and grade. Secondary adenocarcinomas commonly arise from a genitourinary or gastrointestinal origin. Differentiation from primary tumours may be complex. Treatment depends on the prognosis of the primary cancer.