Metastatic rules and clinical significance of lymph nodes in thyroid minimal cancer        FAN Xi-hong*，HE Qing-qing，ZHUANG Da-yong，et al. *Department of Thyroid Breast Surgery, Jinan Military General Hospital, Jinan 250031, China
Corresponding author: FAN Xi-hong, E-mail:fxh1023@yahoo.com.cn
Abstract    Objective To investigate the metastatic rules of cervical lymph nodes in thyroid minimal cancer (TMC), and guide the appropriate treatments. Methods    Cervical lymph node metastasis of 117 cases of TMC performed  cervical lymph node dissection(CLND) from January 1999 to May 2010 in Jinan Military General Hospital was analyzed retrospectively. Characteristics, influencing factors, diagnosis methods and treatment suggestions in regional lymph nodes metastases were analyzed. Results    The rate of lymph nodes metastasis was 53.8%(63/117). The most common areas of cervical lymph nodes metastases was Ⅵ(47.9%), Ⅲ(20.9%), Ⅳ(16.5%), Ⅱ(6.1%)regions respectively. With the increasing of the number of lymph nodes metastases in Ⅵ region, the number of lateral lymph nodes metastases was also increased. Tumor number and size were related to the lymph nodes metastases (P=0.000，P=0.014). The ultrasonography estimates of the lymph nodes metastases sensitivity, specificity and accuracy was 19.0%, 98.1% and 55.5% respectively. The lymph nodes false negative rate was 13.8% by pathological examination in operation. There weren’t recurrences, metastases and deaths in all cases. Conclusion    The regional lymph nodes have high metastases rates in TMC cases. The preoperative evaluation, the intraoperative rapid biopsy and the characteristics of lymph nodes metastases in TMC should be stressed, which is more helpful in guiding clinical treatment. Preventive regional cervical lymph node dissection can  benefit the patients.