Aims
Non-muscle invasive bladder cancer (NMIBC) is a chronic condition requiring frequent follow-up, endoscopic examinations, tumour resections, and intravesical treatments. In this clinical context, patient-reported outcomes (PROs) have enormous potential to inform treatment assessment and recommendations for NMIBC; however, current PRO measures are inadequate for NMIBC because they lack key NMIBC-specific symptoms and side-effects associated with contemporary treatments. This study aimed to develop and evaluate a patient-reported NMIBC Symptom Index (NMIBC-SI) that is acceptable to patients; reliable, valid, and responsive to treatment effects; and fit-for-purpose as an endpoint in clinical trials.
Methods
We developed a draft 104-item NMIBC-SI through a systematic review and interviews with 26 patients and 20 clinicians, and pre-tested using cognitive interviews. We then administered the NMIBC-SI to patients on active treatment from nine Australian sites. NMIBC-SI item responses were analysed and flagged for exclusion if they had low prevalence, were conceptually similar, or highly correlated (≥0.50). Nine Urologists reviewed the results and final items for inclusion.
Results
Planned target accrual, n=220, was reached (178 male, mean age 69.3) representing all risk groups (Low 27.7%; Intermediate 13.2%; High 50.9%). >80% of participants did not experience 21 items, seven items were highly correlated, and four excluded as >50% of urologists rated them not directly related to NMIBC treatment (e.g. “have you had a cough?”). The final 56-item NMIBC-SI includes a 23-item symptom burden scale, two treatment-specific modules, and three optional function scales.
Conclusions
The NMIBC-SI allows comprehensive assessment of patients’ self-reported symptom burden and functioning impairment. A validation study commenced July 2018, recruiting newly diagnosed NMIBC patients from 15 centres across four countries. It will assess key PROs across treatments, disease trajectory (acute to 1-year survivorship), and patient risk categories. The NMIBC-SI will be suitable for use in clinical practice and future clinical trials of treatments for NMIBC.