Where are the inequalities in colorectal cancer care in a country with universal healthcare? A systematic review and narrative synthesis

Objective Patients diagnosed with colorectal cancer living in more deprived areas experience worse survival than those in more affluent areas. Those living in more deprived areas face barriers to accessing timely, quality healthcare. These barriers may contribute to socioeconomic inequalities in survival. We evaluated the literature for any association between socioeconomic group, hospital delay and treatments received among patients with colorectal cancer in the UK, a country with universal healthcare. Design MEDLINE, EMBASE, CINAHL, CENTRAL, SCIE, AMED and PsycINFO were searched from inception to January 2023. Grey literature, including HMIC, BASE and Google Advanced Search, and forward and backward citation searches were conducted. Two reviewers independently reviewed titles, abstracts and full-text articles. Observational UK-based studies were included if they reported socioeconomic measures and an association with either hospital delay or treatments received. The QUIPS tool assessed bias risk, and a narrative synthesis was conducted. The review is reported to Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020. Results 41 of the 7209 identified references were included. 12 studies evaluated 7 different hospital intervals. There was a significant association between area-level deprivation and a longer time from first presentation in primary care to diagnosis. 32 studies evaluated treatments received. There were socioeconomic inequalities in surgery and chemotherapy but not radiotherapy. Conclusion Patients with colorectal cancer face inequalities across the cancer care continuum. Further research is needed to understand why and what evidence-based actions can reduce these inequalities in treatment. Qualitative research of patients and clinicians conducted across various settings would provide a rich understanding of the complex factors that drive these inequalities. Further research should also consider using a causal approach to future studies to considerably strengthen the interpretation. Clinicians can try and mitigate some potential causes of colorectal cancer inequalities, including signposting to financial advice and patient transport schemes. PROSPERO registration number CRD42022347652.