The effect of immunonutrition support on the prognostic nutritional index in the postoperative period in brain tumors

Objective: The prognostic nutritional index (PNI) reflects the immunological response and nutritional status. We evaluated the effect of immunonutrition on PNI in patients with brain tumors receiving chemoradiotherapy and immunonutritional support. Methods: Demographic, laboratory and clinical data were collected retrospectively from 30 consecutive brain tumor patients who received brain chemoradiotherapy between 2019 and 2022 in our clinic and who were given immunonutrition support during their treatment. The cut-off PNI value before adjuvant therapy was calculated in patients who received immunonutrition support in the postoperative period and compared with the PNI values after adjuvant therapy. Results: While glioblastoma patients constitute the majority (60%) of all patients diagnosed as pathological, different histopathological brain tumors were also included in the study (meningioma, oligodendroglioma). The mean albümin value before adjuvant treatment was 4.04 g/dL, while the mean albümin value after adjuvant treatment increased to 4.16 g/dL (p=0,057). The optimal cut-off value for PNI was found to be 45.5 by ROC analysis. PNI was calculated as 49.38 ± 6.03 SD before adjuvant treatment and 49.40 ± 6.12 SD after adjuvant treatment (p>0.05). Retrospective analysis was conducted on over 30 HGG patients who did not receive immunonutritional supplementation containing Arg/gln/HMB (Arginine/glutamine/Beta-Hydroxy Beta-Methylbutyrate). Interestingly, the analysis revealed that the average PNI was 45.15 before adjuvant therapy and decreased to 42.26 after adjuvant therapy, indicating a statistically significant decline in PNI among those without immunonutritional supplementation. This finding suggests a potential beneficial impact of immunonutritional supplementation on PNI. Conclusions: Immunonutrition support has positive effects on PNI and albumin levels in brain tumor patients who will undergo postoperative radiotherapy/chemoradiotherapy. It can be thought that low PNI, which may be an indicator of hematological and nutritional toxicity predicted by brain chemoradiotherapy, can be prevented by immunonutrition support.