Purpose: We designed this retrospective study to identify predictive value of prognostic nutritional index (PNI) and albumin-globulin ratio (AGR) in nasopharyngeal cancer patients (NPC).
Methods: 95 non-metastatic NPC patients were included in the study. AGR was calculated as the absolute counts between albumin and globulin measurements. (Globulin values were obtained via excluding albumin counts from total protein counts). PNI was calculated using the following formula: [10 × serum albumin value (g/dL) + 0.005 × total lymphocyte count] in the peripheral blood (per mm3).
Results: The statistically significant cutoff value of PNI was identified as 45.45 (area under the curve (AUC): 0.636, p = 0.03) for overall survival. The 5-year OS rate for patients with PNI ≤ 45.45 and PNI > 45.45 were 52.9% and 79.0%, respectively. There were statistically significant difference between groups (p = 0.03).The statistically significant cutoff value of AGR was identified as 1.19 (AUC: 0.689, p < 0.01) for overall survival. The 5-year OS rate for patients with AGR ≤ 1.19 and AGR > 1.19 were 57.7% and 82.0%. There were statistically significant differences between the groups (p = 0.04). 5-year OS rate was 42.9% in the high-risk group (low-PNI and low-AGR patients), it was 80.3% in the intermediate group (low PNI and high AGR or high PNI and low AGR) and it was 80.9% in low-risk group (high PNI and high AGR) (p = 0.004). In the multivariate analysis, age and PNI were independent prognostic factors for poorer OS (HR 2.70, 95% CI 1.091-6.719, p = 0.32 and HR 2.44, 95% CI 1.009-5.940, p = 0.48).
Conclusions: Low PNI is independent prognostic factor for poorer OS. Patients with low-PNI and low-AGR have worse survival than patients with high PNI and high AGR.
Keywords: Albumin–globulin ratio; Nasopharyngeal cancer; Overall survival; Prognostic nutritional index.