(P140) Clinical Predictors of Survival for Patients With Stage IV Cancer Referred to Radiation Oncology

Emily Copel, DO, Johnny Kao, MD, Kenneth Gold, MD, Gina Zarilli, MD, Samuel Ryu, MD, David Yens, PhD; Good Samaritan Medical Center; State University of New York, Stony Brook; New York College of Osteopathic Medicine

PURPOSE: To develop a clinically useful predictive model for survival in a heterogeneous group of patients with metastatic cancer referred to radiation oncology.

PATIENTS AND METHODS: From May 2012 to August 2013, a total of 143 consecutive patients with stage IV cancer were prospectively evaluated by a single radiation oncologist. We retrospectively analyzed the effects of 29 patient-, laboratory-, and tumor-related prognostic factors on overall survival (OS), using univariate analysis. Variables that were statistically significant on univariate analysis were entered into a multivariable Cox regression model to identify independent predictors of long-term survival.

RESULTS: The median OS was 5.6 months. Five prognostic factors significantly predicted survival on multivariable analysis: Eastern Cooperative Oncology Group (ECOG) performance status (0/1 vs 2 vs 3/4), number of active tumors (1–5 vs ≥ 6), albumin levels (≥ 3.4 mg/dL vs 2.4–3.3 mg/dL vs < 2.4 mg/dL), altered mental status (no vs yes), and primary tumor site (breast, kidney, or prostate vs other). Risk group stratification was performed by assigning points for adverse prognostic factors, resulting in favorable-, standard-, and poor-risk groups. The median survival was 21.8 months for favorable risk vs 5.5 months for standard risk and 1.5 months for poor risk (P < .001).

CONCLUSIONS: These data suggest that a model that considers performance status, extent of disease, serum albumin, mental status, and primary tumor site represents a clinically relevant tool in radiation oncology to predict survival for patients with stage IV cancer.

Proceedings of the 97th Annual Meeting of the American Radium Society - americanradiumsociety.org