Nutritional Surveillance from Surgery to Post-Radiotherapy in Oral Cavity Cancer: A Prospective Longitudinal Study

Abstract Purpose Patients diagnosed with oral cavity cancer are highly vulnerable to nutritional deterioration due to both tumor-related factors and treatment-induced side effects. This prospective longitudinal study aimed to trace the nutritional progression of these patients using a structured surveillance framework and to examine how key nutritional indicators influence clinical outcomes. Methods The study enrolled 100 individuals with histologically confirmed oral cavity cancer, all of whom were scheduled for surgical resection followed by radiotherapy. Nutritional evaluations—including bioelectrical impedance analysis (BIA) for body composition, handgrip strength (HGS), serum albumin, and dietary intake assessments—were conducted at five critical visits: pre-surgery (V0), post-surgery (V1), before radiotherapy (V2), end of radiotherapy (V3), and one-month post-radiotherapy (V4). Outcome measures included length of hospital stay (LOHS), mucositis severity, hospital re-admissions, and mortality. Results Significant declines were noted in body weight, body mass index (BMI), fat mass, and HGS across treatment phases (p < 0.01). A weight loss greater than 5% was associated with a higher prevalence of Grade III/IV mucositis (p < 0.05). Reduced muscle mass correlated with longer hospital stays, while preoperative hypoalbuminemia (< 3.5 g/dL) was significantly linked to increased mortality (p = 0.022) and readmissions (p = 0.007). No significant association was found between albumin and mucositis severity. Conclusion This study demonstrates a clear link between nutritional deterioration and adverse clinical outcomes in oral cancer patients. Regular, multi-dimensional nutritional monitoring is essential, and early individualized interventions may improve treatment tolerance and patient recovery.