We report the results of a prospective, intent-to-treat (ITT) trial on the costs of selective tumor downsizing (DS) before liver transplantation (LT) for patients affected with hepatocellular carcinoma (HCC). The trial started in January 1997 including adult patients with nodular-type HCC within and beyond the Milan criteria. Patients were downsized with transarterial chemoembolization (TACE), percutaneous ethanol injection (PEI) and/or radiofrequency ablation (RFA) according to clinical predictors. TACE and RFA were performed as inpatient procedures, while PEI was performed on an outpatient basis. Costs of DS were obtained according to the Tuscany Health Reimbursement Fee Catalog adjusted to yearly inflation rates from 1997 through 2005. Data analysis was performed at 1 year after the last enrollment of 198 patients, including 161 (81.3%) who were transplanted: 34 (17.2%) dropped out and 3 (1.5%) were still on the waiting list. One hundred and fifty-two patients (76.7%) underwent DS for a total of 201 procedures: 159 TACE, 39 PEI, and 3 RFA. Overall costs in Euros (euro) of waitlisting were 861,801.24 euro: 548,460 euro (63.7%) for pretransplantation evaluation; 197,994.84 euro (22.9%) for control visits and hospitalizations; and 115.346.4 euro (13.4%) for DS. Mean costs of DS were 758.58 euro +/- 270 euro per downstaged patient (747.53 euro +/- 257.1 euro Milan; 774.01 euro +/- 287.71 euro non-Milan); 582.85 euro +/- 398.87 euro per waitlisted patient (520.28 euro +/- 406.23 euro Milan; 520.28 +/- 364.48 euro non-Milan); and 716.4 euro per transplanted patient (580.67 euro Milan; 1026.76 euro non-Milan; +76.8%). A selective policy of tumor DS increased the costs of LT waitlisting by 13.4%, but due to higher dropout rates among non-Milan patients, the cost utility of DS was 76.8% higher in the Milan group.