We studied atypical cells which were observed through the healing process of the CO₂ laser vaporization. From 1993 to 1995, 24 patients with carcinoma in situ of uterine cervix were treated by CO₂ laser at our outpatient clinic. The cervical Pap. tests and histology from punch biopsy of 24 Patients were examined retrospectively.
In 21 of the 24 (87.5%) patients, no abnormal microscopically findings were observed after treatment, and we thought they were cured.
In 2 of the 21 (9.5%) patients who were cured, atypical cells were transiently observed from 4 to 12 weeks after therapy.
Cytologically, these cells were eosinophilic superficial, intermediate cells with dyskaryosis and showed irregular nuclear ridge. But these cells were different from tissue repair cells or parabasal type dysplastic cells which were observed before treatment.
It was suggested that the origin of these cells were reserve cells that were remained after laser. vaporization and caused dyskaryosis because of rapid maturation during healing.
Therefore, these cells disappeared after 12 weeks without therapy. It was suggested that the evaluation of CO₂ laser vaporization should be performed after follow up for certain period.