The Impact of Non-Compliance to a Standardized Risk-Adjusted Protocol on Recurrence, Progression, and Mortality in Non-Muscle Invasive Bladder Cancer

Abstract

Purpose: Non-muscle invasive bladder cancer (NMIBC) is a potentially curable or controllable disease if strict adherence to a surveillance protocol is followed. Management and surveillance of NMIBC begins at the time of diagnosis up to a few years thereafter. There is scanty data in the literature evaluating the impact of non-compliance with the surveillance protocols on progression, recurrence, and mortality rate.

Patients and methods: An observational, retrospective cohort study recruited data between 2012 and 2017 at two tertiary hospitals. Data were collected consecutively. NMIBC patients who had at least 3 years of follow-up data were included. Patients were divided into different groups based on their compliance with the cystoscopy follow-up protocol as recommended by the European guidelines. We compared the cystoscopy compliant group with the non-compliant group in view of recurrence, progression, and mortality. In addition, missing variable items during surveillance were calculated using a new scoring model to predict adverse outcomes.

Results: Eighty-eight NMIBC patients met our criteria. Recurrence rate (RR), progression rate (PR), metastasis rate (MsR), and mortality rate (MR) are significantly higher in non-compliant group, RR: (92.6%) (P<0.001), PR: (54.1%) (P<0.001), MsR: (37.7%) (P<0.001), MR: (23.5%) (P= 0.002) respectively. In the subgroup analysis, intermediate and high-risk groups have a PR rate of zero in the compliant group, while it is 100% (P<0.001) and 56.4% (P=0.001) in the non-compliant group, respectively. Use of a Kaplan Meier (KM) graph shows that compliant patients had a better survival in comparison to non-compliant patients. Scoring there or more is statistically and clinically significantly associated with higher recurrence, progression, and mortality. RR: (94%) (P=0.016), PR: 49% (P<0.001) and MR (26%) (P=0.012).

Conclusion: Non-compliance to a standardized surveillance protocol in NMIBC is associated statistically and clinically with adverse outcomes in comparison to a compliant group. This mandates strict adherence to surveillance guidelines particularly in patients with high-risk disease.

Keywords: COVID-19; NMIBC; haematuria; urological malignancies.

Figure 1

Comparison of the estimated probability of mortality among compliant versus non-compliant patients in the follow-up of NMIBC based on the Kaplan–Meier method for 5 years post-diagnosis.