[The treatment of severe dysplasias by CO2 laser: the respective indications for vaporization and conization. 84 cases].

Fifty-nine conisations and 25 vaporizations were carried out using laser CO2 in order to treat a series of 84 cases of severe dysplasias (CIN III). After a follow-up of 4 and 12 months (median period of observation 25 months) it was found that out of 74 patients that were followed up in this way 72 had benefitted from the use of the treatment. There were 5 cases however of recurrence of dysplasia (1 CIN I, 2 CIN II, 2 CIN III). These had further treatment with laser. Four of those were controlled properly, the fifth had to have surgery. Complications of treatment did not occur when vaporization was used and only rarely when conisation was used. With vaporisation it is not possible to obtain a piece for histological examination, but if it is done according to precise criteria it is safe (7 mm depth at least and vaporisation carried out to 3 mm beyond the lesions). It can be used particularly in young patients who have never been pregnant. If these have been examined carefully with directed biopsies taken colposcopically and where the lesion is strictly limited to the exocervix and the transformation zone has been seen and the lesion is small (2 cm of less), 84% were controlled therapeutically and using Bruhat's criteria the success rate was 96%. Conisation was effective for every one of the other cases. Laser CO2 probably lessens local complications of the procedure and if vaporization is carried out on the rim of the cervix better control of the condition is obtained (98% controlled in the period under review).