Host metabolic factors and prognosis in patients treated with immune checkpoint inhibitors for advanced malignancies.

Abstract

e14162 Background: It is well established that an altered host metabolism has an impact on cancer outcome, possibly mediated by several mechanisms, including hyperglicaemia, hyperinsulinemia and presence of chronic inflammation. The aim of our analysis was to evaluate the correlation between host metabolism and clinical outcome in patients with advanced melanoma, kidney and non-small cell lung cancer (NSCLC), treated with immune checkpoint inhibitors (anti-CTLA4, anti PD1 and anti PDL1). Methods: The relationship between presence of type 2 diabetes mellitus (DMII) at baseline and outcome was assessed in 187 patients treated with immune checkpoint inhibitors in two cancer centers. Progression Free Survival (PFS) and Overall Survival (OS) were calculated by Kaplan-Meier estimation; multivariate Cox analysis was performed according to age, gender, BMI (normal < 25 kg/m2, overweight 25-30 kg/m2, obese > 30 kg/m2), type of cancer and line of treatment. Results: One-hundred-sixty-eight patients were available for our analysis. Twenty-eight patients (17%) were diabetic at baseline. Median age was 65 (range 25-80); 83 patients were males (49%); 82 (48%) had advanced melanoma, 83 (49%) NSCLC and 3 (3%) kidney cancer. One-hundred-two (60%) patients had BMI < 25, 51 (30%) were overweight and 16 (10%) were obese. The first line of treatment was immunotherapy in 83 (49%) patients. By univariable analysis median PFS was 4.2 months in non diabetics vs 6.4 in diabetics patients (HR 0.95; 95%CI 0.58-1.58); median OS was 6.17 and 9.1 months, respectively (HR 1.00; 95%CI 0.58-1.75). At multivariable analysis, taking into account DMII, BMI, sex, age, line of treatment and type of cancer, we found that BMI ≤25 was associated with a two fold increase in risk of progression (PD) or death (p = 0.005), whereas patients who received immunotherapy as second or subsequent line had a two fold increase in risk of PD or death (p = 0.003). Conclusions: The results of our analysis show that in patients with advanced cancer treated with immune checkpoint inhibitors, the presence of DMII does not adversely affect the clinical outcome. Conversely, lower BMI was associated with a significantly worse PFS and OS, independently from type of cancer, age and gender. As expected, patients who received immunotherapy in later lines of treatment had a significantly shorter survival.