UGT1A1 and neoplasm: Neither hematologic toxicity (grade ≥ 3 in 52.9%, 30.0%, and 33.3%, respectively, of the 6/6, 6/7, and 7/7 genotype groups) nor tumor RR (41.2%, 33%, and 33%, respectively) were found to differ significantly by UGT1A1 genotype.