The Predictive Significance of the Advanced Lung Cancer Inflammation Index (ALI) in Patients with Melanoma Treated with Immunotherapy as Second-Line Therapy

PURPOSE: The advanced lung cancer inflammation index (ALI) is a useful tool to predict the clinical outcome in several malignancies. The ALI not only contains indices related to inflammation but also the body mass index (BMI), which was reported to correlate with the sarcopenic status. However, to date, its predictive significance in metastatic melanoma patients treated with second-line immunotherapy has not been evaluated. METHODS: We retrospectively analyzed data from patients who were diagnosed with metastatic melanoma and treated with immunotherapy as second-line therapy between 2016 and 2019. Weight, height, neutrophil, lymphocyte and serum albumin were collected at baseline prior to receiving immunotherapy. The BMI was calculated by dividing the weight by height squared. The neutrophil-to-lymphocyte ratio (NLR) was calculated by dividing the absolute neutrophil count by the absolute lymphocyte count. The ALI was defined as follows: ALI=BMI×serum albumin/NLR. The receiver operator curve (ROC) was used to determine the best cutoff value for ALI in predicting disease control (consisting of complete response, partial response and stable disease). The aim of this study was to investigate whether the ALI is a predictive indicator for progression-free survival in melanoma patients. RESULTS: Forty-three patients were included in this retrospective cohort study. By ROC, ALI>50.98 before immunotherapy was predictive of disease control. Baseline continuous variables, such as BMI, NLR, C-reactive protein and C-reactive protein-to-albumin ratio, had significantly worse scores in patients of the low-ALI group (n=24) than high-ALI group (n=19). The median progression-free survival was significantly worse in the patients with ALI<50.98 than the patients with ALI>50.98 (2.60 months vs 11.17 months, P = 0.023, hazard ratio: 2.241, 95% confidence interval: 1.167–5.097). CONCLUSION: The advanced lung cancer inflammation index (ALI) >50.98 before immunotherapy is a strong predictor for disease control. The ALI also provides great predictive value for metastatic melanoma patients treated with immunotherapy as second-line therapy.