Prospective, Multi-Center Study Of 5-Fluorouracil (5-Fu) Therapeutic Drug Management (Tdm) In Metastatic Colorectal Cancer (Mcrc) Patients Treated In Routine Clinical Practice.

650Background: Studies have demonstrated that body surface area (BSA)-based dosing of chemotherapy drugs leads to significant individual exposure variability with a substantial risk of under- or overdosing. This study was initiated to validate use of TDM to personalize 5-FU dosing in mCRC patients treated in routine clinical practice. Methods: 75 mCRC patients from 8 German medical centers received up to 6 administrations of infusional 5-FU according to either the AIO (n = 16), FOLFOX6 (n = 26) or FUFOX (n = 33) regimen. Initial infusional 5-FU dosing for all patients was based on BSA. Individual 5-FU exposure (AUC) was measured by an immunoassay using a blood sample drawn during each infusion. To achieve target AUC of 20 to 30 mg•h/L, subsequent infusional 5-FU doses were adjusted according to the previous cycle 5-FU AUC. Tumor markers CEA and CA19-9 were also measured before, during and after treatment. Primary objective was to confirm TDM of infusional 5-FU resulted in an increased proportion of patien...