Comparison of molecular and conventional strategies for followup of superficial bladder cancer using decision analysis.

PURPOSE Patients with superficial bladder cancer require long-term surveillance for recurrence. We compared the cost of cystoscopy and cytology (standard care) to that of urinary markers (modified care) for patients with a history of superficial bladder cancer. MATERIALS AND METHODS We constructed a decision analysis model that compared the 2 strategies for a hypothetical followup interval of 3 years. Probabilities required for the decision tree were based on a cohort of 361 patients diagnosed with superficial bladder cancer from 1987 to 1997. Sensitivity analyses were used to determine whether test sensitivity and specificity would affect cost thresholds. Costs for each strategy were then applied to actual practice patterns. RESULTS The cost of modified care ranged from $158 to $228 for each followup visit when using a urinary marker with a sensitivity and specificity of 95% and 77%, respectively. The cost of standard care was $240 for each followup visit. Based on sensitivity analyses the probability of disease recurrence and urinary marker accuracy were important determinants of expected costs. Mean number of followup assessments for patients followed more than 3 years was 4.3, 2.2 and 1.5 for years 1, 2 and 3, respectively. Cumulative costs of modified care were lower than those of standard care. CONCLUSIONS Urinary marker testing for followup of patients with superficial bladder cancer is less expensive than the standard method of cystoscopy and urinary cytology based on our model. Future studies will be required to consider other factors that could affect the cost advantage of urinary markers, including indirect costs, the psychosocial impact of testing and different surveillance frequencies.