Lymph node metastasis of CN0 papillary thyroid carcinoma / 中华内分泌外科杂志

ABSTRACT

Objective To discuss the metastasis principle of cervical lymph nodes in CN0 papillary thyroid carcinoma(PTC) and to define the proper surgery scope.Methods Clinical data of the 450 cases of CN0 PTC patients undergoing surgery from Feb.2008 to Feb.2011 in the First Hospital,Jilin University were retrospectively analyzed.Results There were 219 (48.67％) pN + cases and 231 (51.33 ％) pN0 cases.In CN0 PTC cases,lymph node metastasis was most commonly detected in area Ⅵ,about 46.22％ (208/450) (unilateral cancer 41.08％,bilateral cancer 58.09％).The lymph node metastasis rate was 4.44％ (20/450),6.00％ (27/450),and 8.89％ (40/450)respectively in area IIa,area Ⅲ,and area Ⅳ.The metastasis of lymph node was rare in Vb area,only about 2.22 ％ (10/450).No metastasis was found in the 2 cases undergoing area I lymph node dissection.When the tumor diameter was no less than 1.0 cm,capsule invaded or multifocal,male,＜ 45 years old,lymph node metastasis rate was significantly increased (P ＜ 0.05).In addition,when the tumor was located at the upper pole of the thyroid,the lymph node metastasis rate was 33.57％ (48/143) in Ⅱa,Ⅲ,Ⅳ areas in the affected side.When the tumor was at the lower pole of the thyroid,the lymph node metastasis rate was 10.48％ (13/124)in the contralateral area Ⅵ.Conclusion Lymph node metastasis occurs most commonly in area Ⅵ in PTC,followed by area Ⅱ a,area Ⅲ,area Ⅳ.Routine lymph node dissection in area Ⅵ is recommended for the initial surgery.When the tumor diameter is ≥ 1.0 cm,thyroid capsule invasion is involved or more than 3 metastasized lymph nodes were found in area Ⅵ,the range of lymph node dissection should properly be expanded to area Ⅱa-Ⅳ.When the tumor is located at the lower pole of the thyroid,area Ⅵ in the contralateral side should be cleaned.If the tumor is located at the upper pole of the thyroid,area Ⅱa,Ⅲ,Ⅳ in the affected side should be cleaned.