Association Between Thoracic Inlet Size and Cervical Anastomosis Outcomes in Oesophageal Cancer Surgery

Background: Cervical anastomosis is widely used in esophageal cancer surgery. Although thoracic inlet size has been associated with anastomotic complications in retrosternal reconstruction, their relevance in posterior mediastinal (PM) reconstruction remains uncertain. This study evaluated whether thoracic inlet dimensions influence postoperative outcomes after cervical anastomosis performed through the PM route. Methods: A retrospective review was conducted on patients who underwent PM reconstruction between January 2021 and March 2025. Preoperative computed tomography was used to measure interclavicular distance (ICD), sterno-vertebral distance (SVD), and thoracic inlet area (TIA). Demographic, operative, and postoperative variables were analyzed. Univariable comparisons were performed according to postoperative mortality, and multivariable logistic regression was used to assess the independent association between TIA and mortality. Results: Sixty-seven patients were included. Postoperative complications occurred in 20 patients (29.9%), and anastomotic leakage was observed in 10 (15.0%). Overall mortality was 13.4% (n = 9). Among non-survivors, 6 patients (66.7%) had anastomotic leakage, compared with 4 of 58 survivors (6.9%). Thoracic inlet area was significantly lower in non-survivors than in survivors (median 513.5 vs 703.3 mm², p = 0.012). In multivariable logistic regression analysis adjusted for age, ASA classification, and sex, TIA demonstrated an inverse association with mortality (OR 0.996, 95% CI 0.992–1.000, p = 0.060), although statistical significance was not retained after adjustment. Conclusions: A smaller thoracic inlet area was associated with increased postoperative mortality after PM esophagectomy. The markedly higher rate of anastomotic leakage among non-survivors suggests that leakage may represent an important clinical pathway linking thoracic inlet geometry to adverse outcomes. Larger multicenter studies are needed to validate the prognostic relevance of thoracic inlet anatomy in PM reconstruction.