Abstract 15: Association of topoisomerase II expression and cancer-specific death in patients with surgically-resected clear cell renal cell carcinoma.
Abstract PURPOSE: Despite the development of prognostic algorithms based on clinico-pathologic features, the ability to identify aggressive forms of clear cell renal cell carcinoma (ccRCC) remains suboptimal. Topoisomerase IIA (TOP2a) is a biomarker of DNA replication and a target for antineoplastic agents. Herein, we evaluate the association of TOP2a expression in ccRCC tumors with pathologic features of aggressiveness and risk of cancer-specific death. METHODS: We identified 947 patients who underwent nephrectomy to treat clinically localized ccRCC between 1/16/1990 and 9/27/2006. TOP2a expression was assessed using IHC and scored as number of positive cells per mm2. We evaluated TOP2a expression using a continuous variable and tertile categories. For associations with pathologic features we employed Kruskal-Wallis tests and for associations with cancer-specific survival we generated Cox proportional hazard regression models. RESULTS: Higher TOP2a expression is associated with later stage, higher grade and higher Mayo SSIGN score (all p < 0.001). The risk of death from RCC increases with increasing TOP2a expression (p trend < 0.0001). Compared to patients in the lowest tertile, those patients with tumors in the highest tertile of TOP2a expression were at increased risk of RCC death (HR=2.31 95% CI 1.64-3.25; p<0.0001). Interestingly, among those patients with low risk disease (SSIGN score 0-3; ∼95% 10 year survival), those with high TOP2a were at increased risk of RCC death (HR=3.09 95% CI 1.29-7.40; p =0.01). CONCLUSION: Higher TOP2a expression is associated with more aggressive pathologic features and increased risk of cancer-specific death among patients undergoing surgery for localized ccRCC. If confirmed, these data support further inquiry for TOP2a as a prognostic and predictive biomarker for ccRCC patients. Citation Format: Richard W. Joseph, Dan Serie, Tracy Hilton, Mansi Parasramka, Jeanette Eckel-Passow, John Cheville, Bradley C. Leibovich, Alexander S. Parker. Association of topoisomerase II expression and cancer-specific death in patients with surgically-resected clear cell renal cell carcinoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 15. doi:10.1158/1538-7445.AM2013-15
Loss of BAP1 protein expression is an independent marker of poor prognosis in patients with low‐risk clear cell renal cell carcinoma