RAC1 and neoplasm: With regard to the site of first postoperative recurrence among the 92 N0 M0 patients, the Rac1 activity and Pak1 protein levels in the primary tumor tissues of patients with retroperitoneal lymph node metastasis (PRLN) (n = 14; 3.99 ± 1.82, 3.61 ± 0.94, respectively) and other organ metastases (3 of lung, one of liver, and one of bone; 6.35 ± 2.35 and 4.49 ± 1.90, respectively) were significantly higher than the levels in patients with bladder recurrence (n = 18; 1.95 ± 0.89, P < 0.0001, 2.32 ± 1.02, P < 0.01, respectively, Figures.