Metabolic Predictors in Risk Stratification for Oral Cavity and Oropharyngeal Cancer Patients Undergoing Free Flap Tissue Transfer: A Retrospective Study.

: Oral and oropharyngeal cancers are highly prevalent and associated with a high mortality. The primary treatment modality is surgery with free flap reconstruction becoming the gold standard. Our study aimed to assess the anthropometric and metabolic predictors of the occurrence of postoperative complications after free flap reconstruction, and to present a PRISM (Predictive Reconstructive Index for Soft-tissue Microflaps) scoring system. : This retrospective cohort study included 92 patients with advanced oral and oropharyngeal squamous cell carcinoma who underwent primary surgical treatment with microvascular free flap reconstruction between 2020 and 2024. Clinical, surgical, and biochemical parameters (operative and flap ischemia time, BMI; serum albumin, total protein, and calcium) were analyzed in relation to postoperative complications. Associations were assessed using correlation analyses and binary logistic regression. Based on the key predictive variables, the PRISM scoring system was developed to estimate perioperative risk. : Underweight or overweight patients showed higher complication rates (Kruskal-Wallis, = 0.019). Longer surgeries were associated with a higher incidence of SIRS, which in turn correlated with increased flap ischemia (Man-Whitney, = 0.032 and 0.039). Lower albumin and total protein levels on the second postoperative day were linked to more complications (Kruskal-Wallis, = 0.001 and 0.010), as were lower calcium levels on the first postoperative day ( = 0.033). Additionally, longer hospitalization was significantly associated with complication severity ( = 0.031). The PRISM score stratified patients into low-, moderate-, and high-risk groups. : Free flap outcomes in oral and oropharyngeal cancer are influenced by SIRS, nutritional status, and surgical factors. Longer surgeries, flap ischemia, low albumin, protein, calcium, and abnormal BMI increased the complication risk. Careful preoperative assessment, optimization of patient condition, and strategies to minimize operative time and ischemia are essential. The PRISM score may help stratify patients and guide clinical decisions.