CD8A and urinary bladder neoplasm: In the present study, regarding the importance of cytotoxic T (CD8+) and memory (CD45RO+) lymphocytes in eradicating tumor cells and the regulatory role of immune cells expressing FOXP3, we attempted to clarify the role of the immune system based on the frequency of CD3+, CD8+ , CD45RO+ and FOXP3+ lymphocytes in both stromal and intratumoral areas of bladder tumors.