Clinical, pathological, and molecular correlations of necrosis in the primary tumor of patients with renal cell carcinoma

Abstract

4643 Background: Presence of histologic necrosis in the primary tumor of patients with renal cell carcinoma (RCC) has been demonstrated to be an important predictor of survival. We investigated the relationship of necrosis to other histologic and clinical factors known to be important prognostic indicators for patients with RCC. Methods: The records of 300 patients undergoing treatment for RCC at UCLA were evaluated for basic clinical information including TNM stage, Eastern Cooperative Oncology Group performance status (ECOG-PS), nuclear grade, and survival. Pathologic slides of the primary tumors were reviewed by a single pathologist. Presence and amount of necrosis were correlated with clinical factors, carbonic anhydrase IX (CAIX) expression, and survival. Results: Patents with necrosis presented with higher T stage (p < 0.0001), metastases (p < 0.0001), greater mean tumor size (p < 0.001) and higher grade (p < 0.0001) compared to patients without necrosis. Extent of necrosis in the primary tumor significantly correlated with T stage, nodal status, metastasis, ECOG-PS, grade, tumor size, and UCLA Integrated Staging System (UISS) (p < 0.01). Patients with necrosis demonstrated a significantly lower 5-year disease specific survival compared to patients without necrosis (36% vs. 75%; p < 0.0001). Multivariate analysis demonstrated grade (p = 0.002), T stage (p < 0.0001), and ECOG-PS (p < 0.0001) to be independent predictors of disease specific survival, while necrosis approached significance (p = 0.07). Presence and extent of necrosis were independent predictors of survival in patients with localized (p < 0.05), but not metastatic (p > 0.05) disease. In patients with clear cell histology, necrosis was also an independent predictor of survival for localized (p = 0.04), but not metastatic (p = 0.49) disease. Conclusions: Presence of necrosis in the primary tumor of patients with RCC is associated with large size, high stage, high grade, and poor ECOG-PS, as well as the presence of distant metastases. The presence of this histologic variant is an independent predictor of poor survival in patients with localized, but not metastatic disease. No significant financial relationships to disclose.