Clinical Role of Programmed Cell Death-1 Expression in Patients with Non-muscle-invasive Bladder Cancer Recurring After Initial Bacillus Calmette–Guérin Therapy

摘要

Background The programmed cell death-1 (PD-1) pathway has been suggested to play an important role in tumor immune escape. We evaluated changes in PD-1 expression before and after Bacillus Calmette–Guérin (BCG) therapy and its prognostic significance in non-muscle-invasive bladder cancer (NMIBC) patients. Methods We examined 78 paired tissue samples of NMIBC in tumors just before BCG therapy and BCG-relapsing tumors, defined as recurrence after achieving disease-free status by initial BCG instillations for 6?months. We counted PD-1-positive cells, and PD-1 expression was defined as high when the number of PD-1-positive cells was more than 18 under ×200 magnification. Results The median number of PD-1-positive cells in tumors just before BCG therapy was 3.5, significantly lower than that in BCG-relapsing tumors (17.0, p ?