OBJECTIVES: A prior retrospective chart review study described treatment patterns and drug-related adverse events (AEs) for mRCC pts treated with sunitinib or sorafenib in a tertiary center in Italy (ECCO-ESMO, 2009).  This study modeled the costs of these treatments and AEs.  METHODS: Medical records were reviewed for non-trial pts with mRCC, ≥18 years old, treated with sunitinib (n=85) or sorafenib (n=60) after January 1, 2005.  Data collected included patients’ health care resource utilization.  Cost data for the Italian health care system were obtained from various sources including published literature and publicly available information from the Italian government.  The components of the total per-patient-per-month (PPPM) costs (in 2008 Euro) included costs of MKI drugs, diagnostic and therapeutic procedures, hospitalizations, management of MKI-treatment-related adverse events (AEs), and prescription drugs for conditions other than mRCC.  RESULTS: Median treatment duration was 6.6 months (sunitinib) and 5.8 months (sorafenib).  Total costs PPPM were (mean±SD) €3868.97±710.49 (sunitinib) and €3448.01±1,178.96 (sorafenib).  MKI drug costs, equal to €3566.33±481.36 (sunitinib) and €3110.85± 622.25 (sorafenib), were the largest contributor to total PPPM costs, followed by AE treatment costs of €107.89±405.42 (sunitinib) and €222.16±991.18 (sorafenib), and procedure costs of €75.48±72.15 (sunitinib) and €79.94 (sorafenib).  Given the median treatment durations, the total cost over the course of first-line MKI treatment is estimated to be €25,535 for sunitinib and €19,998 for sorafenib, with the cost of AE treatment amounting to €712 for sunitinib and €1,289 for sorafenib. CONCLUSIONS: This study used health care resource utilization data from a real clinic setting and costs from published literature to estimate costs associated with MKI treatment in patients with mRCC in Italy.  MKI drug cost was the major contributor to total PPPM cost, followed by the cost associated with treatment of AEs.  This retrospective study is limited by small sample sizes from a single center.