Albumin-globulin ratio is a predictive biomarker of antitumor effect of anti-PD-1 antibody in patients with non-small cell lung cancer.

BACKGROUND

Anti-programmed cell death receptor (PD)-1 antibody treatment results in better prognosis than standard chemotherapy in patients with non-small cell lung cancer (NSCLC), especially those with high PD-ligand 1 (PD-L1) expression. However, several studies have reported a lack of antitumor effect of PD-1 antibody, even in patients with high PD-L1 expression. Therefore, reliable predictors of treatment response are urgently needed. The albumin-globulin ratio (AGR) is associated with prognosis in several cancers. We aimed to determine whether AGR is a predictive biomarker of anti-PD-1 antibody response in patients with NSCLC.

PATIENTS AND METHODS

Seventy-four NSCLC patients treated with anti-PD-1 antibody were retrospectively enrolled. Patients with driver mutations were excluded.

RESULTS

The mean AGR was significantly higher in the disease control (DC) group than in the progressive disease (PD) group (p < 0.001). Receiver operating characteristic curve analysis revealed an AGR cutoff value for dividing patients into the DC or PD groups of 1.17. Multivariate logistic regression analysis showed that a high AGR (≥1.17, cutoff value) was an independent predictor of DC (p = 0.001). Progression-free survival (PFS) and overall survival (OS) were significantly longer in the high-AGR group than in the low-AGR group (p = 0.008, p = 0.002, respectively). Multivariate Cox regression analysis of PFS and OS showed that high AGR was an independent prognostic factor (p = 0.020, p < 0.001, respectively).

CONCLUSION

Pretreatment serum AGR may be a useful predictor for DC and prognostic factor of anti-PD-1 antibody in patients with NSCLC. The clinical utility of AGR still needs to be confirmed in a prospective analysis.