Intra-operative frozen section analysis of common iliac lymph nodes in patients with stage IB1 and IIA1 cervical cancer

INTRODUCTION: To evaluate frozen section analysis of common iliac lymph nodes for developing the accuracy of para-aortic lymphadenectomy and detection of para-aortic lymph node metastasis in patients with stage IB1 and IIA1 cervical cancer treated by surgical intent. METHODS: Three hundred and ninety-two patients with stage IB1 and IIA1 cervical cancer who underwent radical hysterectomy with pelvic and/or para-aortic lymphadenectomy were retrospectively analyzed. Among those patients, 183 (group A) underwent para-aortic lymphadenectomy when para-aortic lymph nodes were identified as suspicious by visualization and palpation. Other 209 patients (group B, underwent intra-operative frozen section analysis of common iliac lymph nodes) underwent para-aortic lymphadenectomy when frozen section analysis was positive, or para-aortic lymph nodes were identified as suspicious metastases by visualization and palpation. RESULTS: We found 21 positive cases (10.0%) of 209 patients by frozen section examination, represented by 1 false negative (4.5%) and 0 false positive case. The specificity and the positive predictive value of frozen section examination were 100%; the negative predictive value was 99.5% (187/188). Overall, the metastasis rates of pelvic lymph node, common iliac lymph node, and para-aortic lymph node were 35.7, 10.2, and 3.3%, respectively. We found the dissection and metastasis rates of para-aortic lymph node in group B statistically significantly higher than group A (14.4% vs. 7.1%, for dissection rates of group B vs. group A, P = 0.022) (5.3% vs. 1.1%, for metastasis rates of group B vs. group A, P = 0.021). CONCLUSION: The frozen section analysis of common iliac lymph nodes can develop the accuracy of the para-aortic lymphadenectomy and metastasis rate of para-aortic lymph node in patients with stage IB1 and IIA1 cervical cancer.