[The rule of metastatic pelvic lymph node distribution in patients with early stage cervical carcinoma].

Objective: To investigate the distribution of metastatic pelvic lymph nodes in the women with early stage cervical carcinoma, and the feasibility of dividing these nodes into three stations in those patients.

Methods: (99m)Tc-DX of 2 ml was injected into the cervix to a depth of 5 to 10 mm at 3, 6, 9, 12 o'clock positions preoperatively in 196 patients with early stage cervical cancer. Pelvic lymphadenectomy and radical hysterectomy were performed in all patients. Pelvic lymph nodes were detected by gamma-probe. The sentinel lymph nodes (SLN) were determined if the radioactivity reached 5 times higher than that in the ipsilateral nodes. All resected pelvic lymph nodes were examined by histopathology with HE stained serial sections.

Results: Of the 196 patients, 41 were found to have metastasis in 83 lymph nodes. The metastatic rate was 78.3% (65/83) in the parametrial and obturator lymph nodes, 20.5% (17/83)in the internal and external iliac lymph nodes, 1.2% (1/83) in the commmon iliac lymph nodes. Of the 22 patients with metastatic parametrial lymph nodes, metastatic external iliac lymph nodes were detected in 5 patients, and metastatic internal iliac lymph nodes in 3 patients. Among the 19 patients with metastatic obturator lymph nodes, metastatic external iliac lymph nodes were found in 4 patients, and metastatic internal iliac lymph nodes in 3 cases. It was shown by Chi-sqare test that the metastases in parametrial and/or obturator lymph nodes were positively correlated with lymph node metastases in other pelvic sites. Eighty-one SLN were found to have metastasis. The metastatic rate of parametrial and obturator SLN was 79.0% (64/81) versus 21.0% (17/81) of internal and external iliac SLN. No statistically significant difference in 1- and 3-yr survival was observed between the groups with and without metastasis in parametrial and obturator lymph nodes, while the 5-yr survival rate in the patients without metastatic lymph node was 93.2%, significantly higher than that of patients with lymphatic metastasis (65.1%).

Conclusion: It is feasible for cervical cancer to divide the pelvic lymph nodes into three levels. The level I lymph nodes consist of parametrial and obturator lymph nodes. Internal and external iliac lymph nodes can be considered as level II lymph nodes, and the common iliac and inguinal lymph nodes as level III nodes. A rational treatment plan can be made according to the distribution of metastatic pelvic lymph nodes.