Time to Diagnosis Among Children and Adolescents With Cancer in Québec, Canada: A Population‐Based Study

BACKGROUND: Timely cancer diagnosis in children and adolescents is important to improving outcomes. We aimed to quantify time to diagnosis and assess variations by patient, demographic and system-level factors. PROCEDURE: We conducted a population-based study of individuals aged 0-19 years diagnosed with one of 12 cancers from 2010 to 2022 in Québec, Canada. The diagnostic interval was defined as the time from first cancer-related healthcare encounter to diagnosis. We calculated medians and interquartile ranges (IQRs) overall and by cancer type and used multivariable quantile regression to identify factors associated with time to diagnosis at the 25th, 50th and 75th percentiles. RESULTS: Among 2927 patients, diagnostic intervals differed by cancer type, age and rurality, but not by sex, material or social deprivation. Median intervals were longest for carcinomas (100 days; IQR 33-192) and shortest for leukaemias (8 days; IQR 3-44). Older children had longer intervals. Compared with children living in Montréal, living in regional areas and other large urban centres was associated with longer 50th and 75th percentiles of time to diagnosis for hepatic (30 days; 95% confidence interval [CI], 6-53) and central nervous system (CNS) tumours (91 days; 95% CI, 23-159). Diagnostic intervals were shorter in 2020-2022 across several cancer sites, with CNS tumours showing reductions across all quantiles and a higher proportion of emergency department visits as the first cancer-related healthcare encounter. CONCLUSION: Shorter diagnostic intervals in 2020-2022 suggest that pandemic-related changes in care pathways may have expedited diagnosis for some cancers.