Among all the clinical parameters, bone and visceral metastases were the only parameters that positively correlated with the expression of K-Ras (P = 0.009, P = 0.046 in CRPC samples and P = 0.01, P = 0.018 in PPC samples), suggesting that K-Ras overexpression may promote bone and visceral metastases. Here, KRAS is linked to primary peritoneal carcinoma.