Objective: The objective of this study is to identify factors predicting intensive care unit (ICU) mortality in cancer patients admitted to a medical ICU. Patients and methods: We conducted a retrospective study in 162 consecutive cancer patients admitted to the medical ICU of a 1000-bed university hospital between January 2009 and June 2012. Medical history, physical and laboratory findings on admission, and therapeutic interventions during ICU stay were recorded. The study end point was ICU mortality. Logistic regression analysis was performed to identify independent risk factors for ICU mortality. Results: The study cohort consisted of 104 (64.2%) patients with solid tumors and 58 patients (35.8%) with hematological malignancies. The major causes of ICU admission were sepsis/septic shock (66.7%) and respiratory failure (63.6%), respectively. Overall ICU mortality rate was 55 % (n = 89). The ICU mortality rates were similar in patients with hematological malignancies and solid tumors (57% vs 53.8%; P = .744). Four variables were independent predictors for ICU mortality in cancer patients: the remission status of the underlying cancer on ICU admission (odds ratio [OR], 0.113; 95% confidence interval [CI], 0.027-0.48; P = .003), Acute Physiology and Chronic Health Evaluation II score (OR, 1.12; 95% CI, 1.032-1.215; P = .007), sepsis/septic shock during ICU stay (OR, 8.94; 95% CI, 2.28-35; P = .002), and vasopressor requirement (OR 16.84; 95% CI, 3.98-71.24; P = .0001). Although Acute Physiology and Chronic Health Evaluation II score (OR, 1.30; 95% CI, 1.054-1.61; P = .014), admission through emergency service (OR, 0.005; 95% CI, 0.00-0.69; P = .035), and vasopressor requirement during ICU stay (OR, 140.64; 95% CI, 3.59-5505.5; P = .008) were independent predictors for ICU mortality in patients with hematological malignancies, Sequential Organ Failure Assessment score (OR, 1.83; 95% CI, 1.29-2.6; P = .001), lactate dehydrogenase level on admission (OR, 1.002; 95% CI, 1-1.005; P = .028), sepsis/septic shock during ICU stay (OR, 138.4; 95% CI, 12.54-1528.4; P = .0001), and complete or partial remission of the underlying cancer (OR, 0.026; 95% CI, 0.002-0.3; P = .004) were the independent risk factors in patients with solid tumors. Conclusion: Intensive care unit mortality rate was 55% in our cancer patients, which suggests that patients with cancer can benefit from ICU admission. We also found that ICU mortality rates of patients with hematological malignancies and solid tumors were similar. © 2014 Elsevier Inc.