4582 Cost-effectiveness of endoscopic ultrasonography in upper gi submucosal tumors: a prospective multicenter study of the german eus-club.

Background : A large number of studies have dealt with the accuracy of endoscopic ultrasonography (EUS) in upper GI submucosal lesions (SML). We aimed at determining the potential influence of EUS on the further management of these lesions and its cost-effectiveness. Methods : In a prospective multicenter study (23 German centers) patients with the suspicion of a SML underwent endoscopy and EUS. Referring physicians were asked about the further management without EUS (without knowledge of EUS results at this time). After obtaining EUS results, they were asked again about their further diagnostic and/or therapeutic approach in the patients, complemented by a 6 month follow-up. These data were then used for a cost-minimization analysis, the endpoint of which was the establishment of the final diagnosis. The frequency of each diagnostic step in the study population was taken for its probability of occurence. For both strategies (with/without EUS) the used ressources and the net costs of a representative hospital were calculated for Germany and the USA (Germany: EUS 148 $, CT 241 $, endoscopy 79 $; USA EUS: 338 $, CT: 205 $, endoscopy 162 $). Data were analyzed using Tree Age Data 3.5. Results were validated with a sensitivity analysis. Results: Final diagnoses: 102 SML, of those 84 tumors (SMT), 18 other lesions, and 48 extraluminal compressions (ELC), mostly by normal structures/ organs. EUS reduced the rate of further diagnostic tests from 93% to 47%, whereby 2 tests were replaced in 38% and 1 test in 72%. 97% of all CTs, 70% of all endoscopic controls and 64% of all large particle biopsies (LPB) were replaced by EUS. In 9 of 10 ELC cases LBP was not performed after EUS; some cases were due to compression by vessels or by the spleen, which would have led to potentially severe complications. For the cost minimzation analysis however, costs of complications were not considered. The costs of the EUS strategy based on German hospital costs, were 207 $/pt., the costs of the strategy without EUS 265 $, these differences being preserved after sensitivity analysis. For the US, From an USA hospital perspective, however, these values were 480 $/pt (EUS strategy) and 362 $/pt. (non-EUS strategy). Conclusions: EUS replaces 2/3 of other tests, among those also potentially hazardous procedures. EUS is also cost-effective in the diagnosis of SML in the German health care system; in the USA, where EUS is substantially more expensive than CT, this advantage of the EUS strategy could not be maintained.