Costo efectividad del uso de 18FDG-PET/CT comparado con CT seguido de 18FDG-PET/CT como prueba confirmatoria de un caso positivo en la evaluación al final del tratamiento en pacientes pediátricos con linfoma hodgkin

Objective To estimate the cost-effectiveness of 18FDG-PET/CT compared to CT followed by 18FDGPET/CT as a confirmatory test for a positive case at the end of treatment in patients less than 18 years with Hodgkin lymphoma. Materials and Methods A decision tree in TreeAge® was built to compare the use of 18FDG-PET/CT with CT followed by 18FDG-PET/CT as a confirmatory test for a positive case in detecting residual lesion at end of treatment in pediatric patients with Hodgkin lymphoma. The perspective was that of the health system, including all direct costs. All monetary amounts are expressed in Colombian pesos of 2010. The outcome was measured in life years gained. The data of the operating characteristics of the tests were taken from the literature. We calculated the costeffectiveness ratio. The threshold was 3 times the per capita GDP per life year gained (the Colombian 2010 per capita GDP was $ 12 047 418 COP). In the absence of reported data for life expectancy of true positives and false negatives, deterministic and probabilistic sensitivity analyzes were performed, in order to identify the effect of differential life expectancy upon the 18FDG-PET/CT cost effectiveness. Results Assuming a difference of 13.4 years in the life expectancy of true positives vs false negatives, the cost of an additional life year gained with 18FDG-PET/CT compared to CT followed by 18FDG-PET/CT as confirmatory test for a positive case in the evaluation at the end of treatment in pediatric patients with Hodgkin lymphoma was 2 789 788 (COP). The results were sensitive to the differential life years gained between true positive and false negative cases, the prevalence of residual lesion, the operating characteristics of the tests and the cost of 18FDG-PET/CT. 18FDG-PET/CT becomes cost effective for life expectancy differences of at least a year. Conclusion If the differential life-expectancy between true positives and false negatives is at least one year, using 18FDG-PET/CT in the evaluation at the end of the treatment of pediatric patients with LH is a cost-effective strategy for Colombia. The size of the differential may have effects on the cost-effectiveness of 18FDG-PET/CT at other stages of diagnosis or treatment.