The impact of pre- and post-operative weight loss and body mass index on prognosis in patients with oesophageal cancer

Background: Weight loss is a cardinal symptom of oesophageal cancer and is often continued after surgery. High body mass index (BMI) is a strong risk factor for oesophageal adenocarcinoma. This study aimed to assess the impact of pre- and post-operative weight loss and BMI on long-term mortality after resection for oesophageal cancer. Methods: This prospective and nationwide cohort study included 390 patients, operated on for oesophageal cancer in Sweden in 2001-2005 with follow-up until 2016, who responded to a questionnaire on weight history 6 months after surgery. Multivariable Cox proportional hazard models provided hazard ratios (HRs) and 95% confidence intervals (95% CIs) of mortality while adjusting for several prognostic factors, including tumour stage. Results: Compared to weight stable patients, pre-surgery weight loss indicated increased HRs of overall all-cause mortality (HR = 1.32, 95% CI 0.94-1.86) and disease-specific mortality (HR = 1.36, 95% CI 0.93-1.98). Patients with >20% weight loss post-surgery had worse overall all-cause mortality (HR = 1.71, 95% CI 1.01-2.88) and disease-specific mortality (HR = 2.20, 95% CI 1.24-3.89). Compared to patients with normal BMI, decreased HRs were indicated for patients who were obese at the time of surgery (overall all cause mortality HR 0.87 95% CI, 0.58-1.31 and disease-specific mortality HR = 0.89, 95% CI 0.57-1.40), while patients with BMI <= 19.9 at 6 months post-surgery had increased all-cause mortality (HR = 1.41, 95% CI 1.03-1.95) and disease-specific mortality (HR = 1.55, 95% CI 1.09-2.21). Conclusion: Post-operative weight loss and low BMI at 6 months post-surgery are independent markers of poor prognosis in patients who undergo surgery for oesophageal cancer. (C) 2017 Elsevier Ltd, BASO similar to The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.