VI. Exploratory analysis of the effect of cytochrome P450, family 3, subfamily A, polypeptide 5 (CYP3A5), cytochrome P450, family 2, subfamily C, polypeptide 8 (CYP2C8), and cytochrome P450, family 2, subfamily B, polypeptide 6 (CYP2B6) polymorphisms on DFS and toxicity.