Nutritional index for immune-checkpoint inhibitor in patients with metastatic gastro-esophageal junction/gastric cancer

Background: Nutritional status is strongly associated to prognosis in mGOJ/GC patients. The aim of the present study was to develop an ICI-specific nutritional index (NI).Methods: Ten serum and anthropometric nutritional markers derived from blood tests or CT scans were analyzed at baseline in patients treated with second-line ICI and correlated with overall survival (OS). An ICI-specific NI (the NUTRIICI) was developed with its specificity assessed in an independent group of patients treated with standard second-line chemotherapy.Results: From June 2014 to December 2018, 57 mGOJ/GC patients (14 females, 43 males) with a median(m) age of 61 years (range 29-85) received ICI as second-line therapy (Pembrolizumab n=26, Nivolumab n=1 6, Avelumab n=15). Among the 10 analyzed variables, Onodera's prognostic NI (PNI) <= 33 and waist-to-hip (WHR) <1 were independent predictors of OS and used to build the NUTRIICI. Patients with both favorable factors (i.e., PNI >33 and WHR >= 1, comparator group) had a mOS of 18.0 vs. 6.7 months of patients with one unfavorable factor (either PNI <= 33 or WHR <1, Hazard Ratio, HR 3.06), vs. 1.3 months of patients with both unfavorable factors (HR 17.56), overall P<0.0001. In the independent group of patients treated with standard chemotherapy NUTRIICI was not associated with prognosis (P=0.57).Conclusions: NUTRIICI is the first ICI-specific NI for mOGJ/GC patients receiving second-line ICI. A validation in larger cohorts is strongly encouraged.