Prognostic Nutritional Index is a valuable preoperative prognostic biomarker in Mexican patients surgically intervened on gastrointestinal stromal tumors: a retrospective cohort study.

Purpose: The immunonutritional status of cancer patients has a profound impact on lifespan. Prognostic Nutritional Index (PNI) evaluates prognosis in operated patients with both neoplastic and non-neoplastic conditions. This study estimates the overall survival (OS) of Mexican patients operated on gastrointestinal stromal tumors (GIST) based on PNI. Methods: Immune-nutritional status was retrospectively analyzed in a cohort of 104 patients operated on GIST. Receiver operating characteristic (ROC) curves and X-tile software were used to estimate the optimal cutoff point and predict OS stratifying patients by PNI. Survival curves were obtained through Kaplan-Meier and log-rank methods. Multivariate analysis of survival was performed by Cox regression. Results: PNI (≥ 36.5) (p = 0.024) and mitotic index (≥ 5) (p = 0.013) were the only independent prognostic scores; the PNI-high group had better survival with 81.5% less risk of death (HR = 0.185). High PNI was correlated with favorable characteristics, i.e., low/intermediate risk (p = 0.046), reduced mitotic index (< 5) (p = 0.001), and younger age (< 55 years, p = 0.047). Conclusions: PNI ≥ 36.5 entails a better prognosis for Mexican patients with surgically resected GIST. PNI represents a simple, reliable, and cost-effective prognostic tool, besides the pathological approach. [ABSTRACT FROM AUTHOR]