Understanding ethnic inequalities in diagnostic intervals of cancer: a cohort study of patients presenting suspected cancer symptoms to general practitioners in England.

Abstract

Background: UK Asian and black patients experience longer cancer diagnostic intervals - period between initial symptomatic presentation in primary care and cancer diagnosis.

Aim: To determine whether these differences are due to prolonged primary care intervals (period between first primary care presentation and secondary care referral), referral interval (period between referral and first secondary-care appointment) or secondary care interval (period between the first secondary care appointment and diagnosis).

Design and setting: We conducted a cohort study of patients with seven common cancers (breast, lung, prostate, colorectal, oesophagogastric, myeloma, and ovarian), diagnosed after presenting symptoms in English primary care.

Methods: Information on symptom presentation and cancer diagnosis was extracted from cancer registry-linked primary care data. Accelerated failure-time models were used to investigate ethnic differences across all four intervals.

Results: Across all sites, diagnostic intervals were longer for Asian and black patients compared to white patients. Site-specific analyses showed that, for myeloma, lung, prostate, and colorectal, the secondary care interval was longer in Asian and black patients who also had longer primary care interval in breast and colorectal cancer. There was little evidence of ethnic differences in referral interval.

Conclusion: We found evidence of ethnic differences in diagnostic intervals, with prolonged secondary care intervals for four common cancers and prolonged primary care intervals for two. Although these differences are relatively modest, they are unjustified and may indicate shortcomings in healthcare delivery that disproportionately affect ethnic minorities.