Prognostic significance of RB1-inducible coiled-coil 1 in salivary gland cancers

Background No generally agreed‐upon method is available for predicting the prognosis of salivary gland cancers. RB1‐inducible coiled‐coil 1 (RB1CC1) is a positive regulator for the retinoblastoma tumor suppressor (RB1) pathway, and is a suitable marker for evaluating the clinical course of breast cancer. We investigated whether RB1CC1 predicts the prognosis of salivary gland cancers. Methods Molecules involved in the RB1CC1 pathway, including RB1CC1, RB1, p53, and Ki‐67, were evaluated immunohistochemically in 36 cases of salivary gland cancers. The relationships between clinicopathologic features and disease‐free‐survival intervals were analyzed by a Kaplan–Meier log‐rank test and a multivariate Cox proportional hazard regression. Results Nuclear RB1CC1 loss in the tumors was significantly associated with a worse disease‐free survival (log‐rank test, chi‐square value = 11.644, p = .0006), and was the maximum critical risk (multivariate Cox proportional hazard ratio = 11.112, 95% confidence interval [CI] = 1.776–69.510, p = .0100). Conclusions Nuclear expression of RB1CC1 predicts a better clinical outcome and is useful in the follow‐up of salivary gland cancers. © 2011 Wiley Periodicals, Inc. Head Neck, 2012