Biological Age Reflects Physical Condition and Predicts Postoperative Complications Beyond Chronological Age in Patients With Esophageal Squamous Cell Carcinoma Undergoing Minimally Invasive Esophagectomy

Background Chronological age is an important indicator of the physical condition; however, it may not fully capture their physiological status. Recently, biological age has gained attention as a more accurate predictor of physical condition. This study aimed to investigate the association between biological age and postoperative outcomes in patients with esophageal squamous cell carcinoma (ESCC). Methods This study included 345 patients with ESCC who underwent minimally invasive esophagectomy at Kobe University Hospital. Biological age was estimated using Levine et al.’s model based on data from nine commonly used blood tests. Patients were stratified by biological age: ≥ 75 years and < 75 years. Results Patients with biological age ≥ 75 years ( N = 59) were more likely to be male ( p = 0.012) and had lower serum albumin levels ( p = 0.0003) and higher creatinine levels ( p = 0.0009) than those with biological age < 75 years ( N = 286). Regarding postoperative complications, patients aged ≥ 75 years had higher rates of pulmonary complications ( p = 0.032) and anastomotic leakage ( p = 0.038). No significant differences were observed in overall survival between the ≥ 75 and < 75 age groups, regardless of disease stage. In patients with advanced ESCC, 93% of those with chronological age < 75 years and biological age ≥ 75 years ( N = 27) received preoperative chemotherapy. Conversely, only 80% of patients with chronological age ≥ 75 years and biological age < 75 years ( N = 20), who had better general condition, received preoperative chemotherapy. Conclusions Biological age is associated with postoperative complications. Assessing physical condition using biological age may help determine patients' eligibility for preoperative chemotherapy.