DPYD and Thrombocytopenia: Significant associations were identified between both DPYD c.1905+1G/A (OR, 9.69 [95% CI, 1.56–60.39]; P = 0.02) and DPYD c.2846A/T (OR, 9.69 [95% CI, 1.56–60.39]; P = 0.02) variants and grade ≥3 stomatitis (Supplementary Table 4) and between DPYD c.1905+1G/A and grade ≥ 3 thrombocytopenia (OR, 21.50 [95% CI, 2.02–228.16]; P = 0.01).