Histologic Comparison of Ablative Techniques for Endometriosis: A Randomized Trial

Abstract

Study Objective

To compare ablative energy technologies and evaluate their ability to destroy native endometriosis tissue in humans.

Design

Prospective, randomized, triple-arm, single-blind, clinical trial.

Setting

Good Samaritan Hospital, Cincinnati, Ohio.

Patients or Participants

Women undergoing excision of lesions for pelvic pain symptoms or endometriosis by a high-volume minimally invasive gynecologic surgeon.

Interventions

During the already planned excision of lesions, just prior to excision, identified lesions were uniquely numbered and randomized to ablative treatment with either 1) electrical diathermy, 2) Argon beam coagulation, or 3) CO₂ laser. The lesions were ablated with the assigned technologies. Excision of the ablated lesions was then performed for pathologic evaluation.

Measurements and Primary Results

The primary outcome was the frequency of positive histology for endometriosis within the ablated surgical specimens. Sample size was calculated in advance to be 140 samples, which would provide power of 0.8 and significance of 0.0167. A total of 153 samples of ablated lesions were excised and collected from a total of 34 patients, with 51 samples in each of the three surgical technology arms. Overall, 20 (13%) of the ablated lesions still contained endometriosis identified on pathology after subsequent excision. Stratified by treatment arm, the numbers of specimens that remained endometriosis-positive after ablative treatment were 10 (20%) for electrical diathermy, 4 (8%) for Argon beam coagulation, and 6 (12%) for CO₂ Laser (p=0.20).

Conclusion

Endometriosis lesions are incompletely treated at similar rates with electrical diathermy, Argon beam coagulation, or CO₂ laser. Excision of these areas post-ablation removes more disease. Histologic effectiveness of these treatments stratified by stage or depth of lesions remains to be elucidated.