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Published on: March 8, 2012
A study comparing LETZ and CO2 laser treatment for cervical intra epithelial neoplasia with and without associated
K S Raju1, E Henderson, A Trehan
1Department of Obstetrics and Gynaecology, St. Thomas' Hospital UMDS, London, UK.
Objective:
To evaluate the recurrence of cervical intraepithelial neoplasia (CIN) following treatment with CO2 laser ablation and loop excision of the transformation zone (LETZ) and its correlation with the presence of HPV.
Methods:
Six hundred and forty two women diagnosed as having CIN were treated either by CO2 laser (318) or LETZ (324) and were followed up for a minimum of 12 months. Recurrence rates in each group were evaluated and correlated with the presence or absence of HPV prior to treatment.
Results:
There was a considerably higher rate of recurrent disease observed after treatment with laser ablation than LETZ (9% after LETZ and 37% after laser ablation) p < 0.001. Two hundred and sixty four women (41%) had HPV infection prior to treatment and 29% of these required further treatment for recurrent CIN whereas there were only 11% of women out of the 374 who had no evidence of HPV infection p < 0.001.
Conclusion:
Treatment of CIN in the presence of HPV infection results in higher failure rates and this is significantly increased when the treatment is by laser ablation rather than by LETZ.

