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

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. 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. 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). 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.