The following factors were identified as risk factors for predicting tumor recurrence after surgery: dumbbell-shaped tumor morphology (OR = 4.981, P = 0.031), irregular morphology (OR = 4.816, P = 0.039), lobulated shape (OR = 10.446, P = 0.022), subtotal resection (OR = 3.522, P = 0.002), major resection (OR = 43.685, P = 0.001), PRL positivity (OR = 0.226, P = 0.007), Ki-67 ≧ 3 (OR = 3.14, P = 0.042), T2 signal ratio (OR = 3.17, P = 0.046). Here, PRL is linked to neoplasm.