Abstract
Background: The aim of this study was to evaluate potential disparities in the probability of undergoing surgical treatment among patients with synchronous colorectal liver metastases (CRLM) and to investigate which non-tumour-related characteristics influenced postoperative outcomes. Methods: This was a population-based study of all patients diagnosed with synchronous CRLM between 2015 and 2021 in the Netherlands. Data were retrieved from the Netherlands Cancer Registry (NCR) and data of patients who underwent surgical exploration were retrieved from the Dutch Hepato Biliary Audit (DHBA). The association between non-tumour-related factors, the chance of getting local treatment of CRLM and outcomes after resection were evaluated using multivariable logistic regression models. Results: From the NCR, 14,047 patients with synchronous CRLM were included. Of these 2753 (20 %) patients underwent local treatment of CRLM. Non-tumour-related factors associated with a lower likelihood of local treatment of CRLM included age (OR 0.94 95 %CI 0.94–0.95) and female sex (OR 0.87, 95 %CI 0.78–0.97). Middle and high Socioeconomic status (SES) compared to low SES (respectively OR 1.35, 95 %CI 1.18–1.54 and OR 1.61, 95 %CI 1.41–1.84) and presentation in a hospital that performed liver surgery (OR 1.52, 95 %CI 1.26–1.84) were associated with a higher likelihood of getting local treatment. From the DHBA 2535 patients were included. Non-tumour-related factors associated with both major morbidity and mortality included age (OR 1.01 95 %CI 1.00–1.03 and OR 1.07, 95 %CI 1.02–1.11, respectively) and ASA-score ≥3 (OR 1.7, 95 %CI 1.34–2.29 and OR 2.88, 95 CI 1.92–1.11) respectively. Conclusion: In addition to tumour-related factors, non-tumour-related factors, including age, male sex, SES and hospital of presentation, all contributed to the likelihood of getting local treatment for CRLM. As not all these factors influence postoperative outcomes, healthcare systems should also focus on eliminating barriers to accessing appropriate care.