1879 Comparison of MRI, PET-CT, and Frozen Biopsy in The Evaluation of Lymph Node Status Before Fertility-Sparing Robotic or Laparoscopic Radical Trachelectomy in Early Stage Cervical Cancer

Abstract

Study Objective To compare the accuracy of MRI, PET-CT, and frozen biopsy before fertility-sparing radical trachelectomy in early stage cervical cancer. Design This was a retrospective study on 134 young women with early stage cervical cancer who tried fertility-sparing laparoscopic or robotic radical trachelectomy. All patients underwent preoperative MRI and PET-CT. Comprehensive lymph node dissection was performed during surgery. Retrieved lymph nodes were sent for frozen biopsy before undertaking radical trachelectomy. The diagnostic accuracy of MRI, PET-CT, and frozen biopsy was compared using McNemar test and logistic regression using generalized estimating equations. The final pathologic report on lymph nodes was the gold standard for diagnosis. Setting University hospital. Patients or Participants 134 patients with early stage cervical cancer. Interventions Fertility-sparing, robotic or laparoscopic radical trachelectomy. Measurements and Main Results The retrieved lymph nodes totaled 3362 and mean of retrieved lymph nodes was 25 (range 7- 96). Twenty patients (14.9%) showed positive lymph node areas and 39 out of 986 (4.0%) lymph nodes areas were positive. There was no significant difference in sensitivity (22.6% versus 31.0%, p>0.99), specificity (94.3% versus 95.3%, p=0.83), and accuracy (90.8% versus 92.3%, p=0.5) between MRI and PET-CT in station-by-station analysis. There was significant difference in sensitivity, specificity, accuracy between MRI and frozen biopsy in station-by-station analysis. There was also a significant difference between PET-CT and frozen biopsy. Conclusion When comparing patients with patients, frozen biopsy approach is significantly better than MRI and PET-CT to evaluate sensitivity, specificity, and accuracy. Frozen biopsy of all lymph nodes retrieved during surgery is still the best method to evaluate lymph node status before fertility-sparing radical trachelectomy.