Comparative costs of metal versus plastic biliary stent strategies for malignant obstructive jaundice by decision analysis.

BACKGROUND

For palliation of patients with malignant obstructive jaundice, expansile metal stents provide longer patency than plastic stents but are more expensive. The optimal cost-effective strategy has not been established. Our aim was to compare the relative costs of 3 strategies: (1) plastic stent, with exchange on occlusion; (2) metal stent initially, with coaxial plastic stent insertion in the event of occlusion; or (3) plastic stent initially, with metal stent exchange in the event of occlusion.

METHODS

A decision analysis model was created using DATA 2.6 software to assess the relative costs of the three strategies. Values for variables including the probabilities of reintervention and patient survival were obtained from published data. Costs were based on Medicare reimbursements of hospital charges, and the model was evaluated from the perspective of a third-party payer. One-way and two-way sensitivity analysis of the variables was performed over a wide range.

RESULTS

The outcome is highly sensitive to the ratio of metal stent cost relative to endoscopic retrograde cholangiopancreatography cost (cost ratio M:ERCP) and to the length of survival of the patient. The most economical strategies were (2), (3) and (1) for M:ERCP cost ratios of <0.5, 0.5 to 0.7, and >0.7, respectively.

CONCLUSIONS

The choice of stent should be guided by the relative local costs of ERCP and metal stents and by the prognosis of the patient. At current metal stent costs and Medicare reimbursement rates, initial placement of a plastic stent, followed by metal stent placement at first occlusion in longer survivors, is an economical option. If metal stent cost is less than half of ERCP cost, then initial insertion of a metal stent would be most economical. Use of plastic stents is preferable for patients surviving less than 4 months, whereas metal stents are more economical for patients with longer survival.