When facing small benign non-functional adrenal incidentaloma, patients and urologists must decide between follow-up and surgery. This decision hinges on the critical issues of effectiveness, morbidity, and cost. Both options have good outcomes. Only I Belmihoub8 repoted one case that benign adrenal incidentaloma progressed adrenocortical carcinoma. Loh HH7 reported that no surgery is done due to primary adrenal malignancy during follow-up. Likewise, the morbidity of surgery is mild9–12. Cost may, therefore, play an important role in directing clinical decisions in this disease. A detailed decision-tree model was developed for projecting the management costs for small benign non-functional adrenal incidentaloma. The model’s advantage lies in the ease with which various hypotheses can be rapidly tested through the use of sensitivity analysis.
Enhanced recovery after surgery(ERAS) is popular nowadays, however, shortening length of stay(LOS) does not meet the equivalent point in our model. ERAS could not make immediate surgery less cost than follow-up.
The current model includes treatment-related morbidity, because the various cost derived from the actual charge from patients and/or medical insurance bureau. Three of 21 patients had surgery complication, which is similar with other reports9–12. One patient complicated major hemorrhage and transferred to open surgery, another one had urinary infection and fever, the third one had pneumonia after surgery. Although these three patients stayed longer than average length of stay and cost more than the others, they were discharged with good health finally.
It is important to differentiate the cost analysis presented here from a formal cost-effectiveness analysis. Given the small relative differences in mortality among follow-up and immediate surgery, use of mortality as a measure of effectiveness is unavailable. An alternative strategy would be to assign estimated quality-of-life utility values to all the outcome states within the model. As noted previously, the morbidity differences between follow-up and immediate surgery are also likely to be small. Estimates based on such small and controversial differences in morbidity would add an unacceptable degree of systematic error to results, and would cloud their interpretation. As more comprehensive morbidity data become available, however, extension of this analysis to include effectiveness would likely be valuable.
It is critical to appreciate the limitations as well as the strengths of a modeling exercise of this type. Any model depends on a set of critical assumptions, some of which can
be supported by the literature, whereas others are simply estimates or reflect local clinical practice. Cost modeling is also inherently dependent on institution and region, and
these results may not be valid for all institutions. Yet the structure of the model reflects general management principles for small benign non-functional adrenal incidentaloma, and should be easily translated to other centers provided that institution-specific cost components are modified.
Finally, because we examined the costs from the perspective of the medical establishment, indirect costs, such as psychological factor, were not included. No published work is available regarding the indirect costs of follow-up vs immediate surgery. This is an area worthy of additional study.