Development and internal validation of the survival time risk score in patients treated for oesophageal cancer with palliative intent in South Africa

Background: Most patients who present to South African state hospitals with advanced stage oesophageal squamous cell cancer (OSCC) disease receive palliative treatment. This study aimed to assess the factors that influence survival in patients with OSCC who received palliative management and to develop a prognostic score to aid clinicians in decisionmaking. Methods: Analysis of a prospectively collected database assessed factors influencing survival of patients diagnosed with OSCC receiving palliative treatment. Factors assessed included patient demographics, clinical and laboratory data and tumour factors. A multivariable logistic regression model was used to assess for significant factors associated with survival time and a prognostic score was developed and internally validated based on these factors. Results: There were 384 patients with a male-to-female ratio of 1.3:1. The median survival of the cohort was 3.7 months. Factors that influenced survival on multivariate analysis included area of residence (aOR 1.82, 95% CI 1.02-3.24), performance status (aOR 2.56, 95% CI 1.50-4.35), body mass index (aOR 1.87, 95% CI 1.14-3.06) and serum albumin (aOR 3.06, 95% CI 1.46-6.42). The final prognostic score contained three of the four independent variables based on the regression coefficient for each variable. After internal validation, the risk score maintained fair discrimination and good calibration. Conclusion: The prognostic scoring system based on patient performance status, body mass index and serum albumin, if validated on an independent cohort, would allow more objective decisions on whether to stage or not prior to embarking on palliative treatment, streamlining care and improving quality of life.