J. M. Sharib1, K. Wimmer1, A. L. Fonseca3, S. Hatcher1, L. Esserman1, A. Maitra2, Y. Shen4, E. Ozanne5, K. S. Kirkwood1 1University Of California – San Francisco,Surgery,San Francisco, CA, USA 2University Of Texas MD Anderson Cancer Center,Pathology,Houston, TX, USA 3University Of Texas MD Anderson Cancer Center,Surgery,Houston, TX, USA 4University Of Texas MD Anderson Cancer Center,Biostatistics,Houston, TX, USA 5University Of Utah,Population Health Sciences,Salt Lake City, UT, USA
Introduction: Consensus guidelines recommend resection of intraductal papillary mucinous neoplasms (IPMN) with high risk stigmata, and laborious surveillance for cysts with worrisome features. In practice, resections are performed at higher rates due to fear of malignancy. As a result, many cysts harboring no or low grade dysplasia (LGD) are removed unnecessarily, with undue risk to patients. This study compares the costs and effectiveness of practice patterns at UCSF and MD Anderson to alternative management strategies for pancreatic cysts. Potential cost savings that would be realized if diagnostic accuracy were improved and prevented resection of LGD are also estimated.
Methods: We developed a decision analytic model to compare costs and effectiveness of three treatment strategies for a newly diagnosed pancreatic cyst: 1) Immediate surgery, 2) Do nothing, and 3) “Surveillance” based on consensus guidelines. Model estimates were derived from published literature and retrospective data for pancreatic cyst resections at UCSF and MD Anderson from 2005-2016. Costs and effectiveness (quality adjusted life years, QALYs) were predicted and used to develop incremental cost effectiveness ratios (ICERs). To estimate the cost burden of resecting LGD, the “Surveillance” strategy was adjusted to remove the possibility of resecting LGD, “Precision Surveillance”, and these costs were compared with the original model.
Results: The “Immediate surgery” strategy was the costliest and most effective, while the “Do nothing” strategy was least costly and least effective (Fig 1a). The “Surveillance” strategy was the preferred strategy, however, it increased costs by $129,372 per quality adjusted life year gained (ICER) compared to “Do nothing”; above the commonly accepted $100,000/QALY willingness to pay threshold. When resection of LGD was eliminated, the cost of “Precision Surveillance” decreased by $21,295, while the effectiveness increased by 0.6 QALY, making it the preferred strategy (Fig 1b). The resulting incremental cost discount of “Precision Surgery” was $35,905 per QALY compared to “Surveillance” with current diagnostic accuracy. This cost reduction brought the “Precision Surveillance” strategy below the $100,000/QALY threshold compared to the “Do Nothing” strategy.
Conclusion: Surveillance under current consensus guidelines for IPMN is the preferred strategy compared to the ”Immediate surgery” and “Do nothing” strategies. Our present inability to distinguish LGD from high grade/invasive lesions adds significant costs to the treatment of IPMN. Improved diagnostics that accurately grade cystic pancreatic neoplasms and empower clinicians to reduce the resection of LGD would decrease overall costs and improve effectiveness of surveillance.
