CEA (CEACAM5) expression is common in muscle-invasive urothelial carcinoma of the bladder but unrelated to the disease course

Objectives: Carcinoembryonic antigen (CEA) is a cell surface glycoprotein that represents a promising therapeutic target. Serum measurement of shedded CEA can be utilized for monitoring of cancer patients. Material and Methods: To evaluate the potential clinical significance of CEA expression in urothelial bladder neoplasms, CEA was analysed by immunohistochemistry in more than 2500 urothelial bladder carcinomas in a tissue microarray format. Results: CEA staining was largely absent in normal urothelial cells but was observed in 30.4% of urothelial bladder carcinomas including 406 (16.7%) with weak, 140 (5.8%) with moderate, and 192 (7.9%) with strong staining. CEA positivity occurred in 10.9% of 411 pTaG2 low-grade, 32.0% of 178 pTaG2 high-grade, and 43.0% of 93 pTaG3 tumours (p < 0.0001). In 1335 pT2-4 carcinomas, CEA positivity (34.1%) was lower than in pTaG3 tumours. Within pT2-4 carcinomas, CEA staining was unrelated to pT, pN, grade, L-status, V-status, overall survival, recurrence free survival, and cancer specific survival (p > 0.25). Conclusion: CEA increases markedly with grade progression in pTa tumours, and expression occurs in a significant fraction of pT2-4 urothelial bladder carcinomas. The high rate of CEA positivity in pT2-4 carcinomas offers the opportunity of using CEA serum measurement for monitoring the clinical course of these cancers. Moreover, CEA positive urothelial carcinomas are candidates for a treatment by targeted anti-CEA drugs.