Impact of COVID-19 on stage migration in bladder cancer: A single-centre retrospective comparative cohort analysis

Objectives: To evaluate whether the COVID-19 pandemic has increased the proportion of patients diagnosed with muscle invasive bladder cancer (MIBC) at first presentation and explore potential causes for this hypothesised stage migration. Subjects/Patients and Methods: All patients undergoing first transuretheral resection of bladder tumour (TURBT) between 2 January 2018 and 30 June 2021. The date of the lockdown restrictions was used to divide patients into pre-COVID and COVID cohorts. Data were collated retrospectively from electronic patient records. Variables included demographics data, TNM stage and presentation (emergent/elective). A comparative analysis of the two cohorts was undertaken using the chi-square test to evaluate for statistical significance. A p-value of <0.05 was regarded as significant. Results: A total of 1064 patient underwent a TURBT for a suspected bladder cancer in the study period. The number of patients in the pre-COVID and COVID cohorts was 704 and 360, respectively. Mean age was comparable between cohorts (74.7 vs 74.2 (p = 0.46)) as was sex ratio (F:M (1:2.84 vs 1:2.95) p = 0.80). The proportion of patients with MIBC pre-COVID was 18% compared to 23.6% in the COVID cohort. This represents a 5.6% increase in the prevalence of first presentation MIBC during the COVID era (p = 0.03 [95% confidence interval (CI) = 0.2-10.4]). The odds of a patient presenting with MIBC was 38% higher during the COVID era versus pre-COVID (odds ratio (OR) [95% CI] = 1.38 [1.01-1.85]). A significantly higher proportion of patients had metastases at presentation in the COVID cohort versus pre-COVID (4.4% vs 2.1% (p = 0.034)). Conclusion: Our data would support the hypothesis that the COVID pandemic has precipitated a stage migration in the presentation of bladder cancer towards muscle invasive disease. This has implications in terms of patient outcomes as well as an increased demand on services to provide radial treatment. Potential reasons for the stage migration are patient-related factors and pathway failure due to widespread service disruption caused by COVID-19. Level of evidence: 3