Promoter methylation of RASSF1A gene may be involved in the early-stage during thyroid tumorigenesis, and the similar change in P16INK4a gene is related to lymphatic metastasis of PTC.

• 5．甲状腺乳头状癌组织中RASSF1A基因启动子甲基化可能出现在甲状腺肿瘤发生的早期阶段，P16INK4a基因启动子甲基化在甲状腺乳头状癌的淋巴转移中发挥一定作用。