Univariate analysis revealed that disease-free survival (DFS) was significantly correlated with maxSUV (<7 versus ≥7, p = 0.001),% Ki-67 expression (<25% versus ≥25%, p = 0.047), tumor size (<3 cm versus ≥3 cm, p = 0.027), and tumor cell differentiation (well / moderate versus poor, p = 0.011).