Decreased total psoas muscle area after neoadjuvant therapy is a predictor of increased mortality in patients undergoing oesophageal cancer resection

Background Oesophagectomy for locally advanced cancer carries high rates of morbidity and mortality. Patients require a thorough risk assessment alongside preoperative counselling. Total psoas area (TPA) measurements have been used as a surrogate marker of sarcopenia to predict post‐operative complications in oesophageal cancer patients. No studies to date have determined whether there is an association between the proportion of TPA lost during neoadjuvant therapy and post‐operative outcomes. Methods Clinical data and imaging of patients who underwent neoadjuvant therapy followed by open two‐stage oesophagectomy between January 2008 and April 2018 were analysed retrospectively. Patients who did not undergo restaging computed tomography scan prior to surgery were excluded from the study. The TPA was measured on two cross‐sectional slices at L4 on computed tomography scans pre‐ and post‐neoadjuvant therapy. Results A total of 53 patients who met inclusion criteria were identified. The mean loss of TPA was 7.3%. Patients who had a decrease of TPA of more than 4% had significantly increased 30‐day mortality compared to those who lost 4% or less (24% versus 0%, P = 0.02). Patients aged over 65 years who also had a loss of TPA >4% had significantly increased 30‐day mortality (37% versus 2.9%, odds ratio 19, P = 0.008). Conclusion A decrease in TPA of >4% is associated with a significantly higher risk of post‐operative mortality in patients undergoing neoadjuvant therapy followed by oesophagectomy. Measuring the loss of TPA during neoadjuvant treatment could be a novel aid to preoperative risk assessment. The total psoas muscle area (TPA) has been used as a measurement of frailty and can be easily measured on computed tomography scans. In patients undergoing curative treatment for oesophageal cancer, there is a significant decrease in their TPA during their neoadjuvant therapy. A decrease of greater than 4% of their TPA is associated with high post‐operative mortality in these patients.