This came from the Nationall Institute of Health:
Results: We observed elevated PSA in 27 men (75%) during BCG treatment, of whom 15 (41.6%) had a clinically significant elevation. Overall average PSA increased from 1.3 ng./ml. before BCG instillation to 3.8 during treatment (range 0.1 to 21.5, p <0.0001). In those with a clinically significant elevation average PSA increased from 2.31 ng./ml. at baseline to 6.97 during treatment (p <0.0001) and returned to 3.86 ng./ml. 3 months after treatment. Palpation demonstrated prostatic findings in 10 patients, including firm nodules in 7, while there was significantly elevated PSA in 5 with firm nodules and 2 with diffuse prostatic enlargement. Histological examination of the prostate in 10 patients was diagnostic for granulomatous prostatitis, nonspecific inflammation and benign prostatic hyperplasia in 3, 3 and 4, respectively, of whom none had prostate cancer.Conclusions: Intravesical BCG therapy is associated with significantly elevated PSA in up to 40% of cases. This effect is self-limited and PSA reverts to normal in 3 months. Therefore, we suggest that prostate biopsy be withheld in such patients and PSA monitored.