[Outcome prediction of single-period CO(2) laser therapy for vulvar condylomata acuminate]

To evaluate the outcome of CO(2) laser treatment as primary therapy for vulvar condylomata acuminate and examine the risk factors and prediction model of single-period CO(2) laser treatment.

Between March 2009 and December 2010, a multicenter prospective study was conducted at three 3A hospitals of China (Peking Union Medical College Hospital, Zhejiang Women's Health Hospital & Tongji Hospital). All enrolled patients of vulvar condylomata acuminata received CO(2) laser vaporization as the primary therapy and had return visits at 1, 3 and 6 months individually after treatment. Therapeutic recurrence and side effects were recorded. Logistic regression was used to analyze the associations between demographic or clinical characteristics and the outcome of single-period CO(2) laser treatment and a prediction model was established subsequently. The optimal cutoff value of model was evaluated by area under the receiver operating characteristic curve (AUC ROC).

A total of 160 patients completed a 6-month follow-up with a loss rate of 9.1% (16/176). And 131 patients (82%) were cured after the single-period CO(2) laser therapy with a total recovery rate of 94% (150/160). Side effects occurred in 50 (31%) patients with a complete self-recovery within 6 months. The most common side effects were local ulceration, pain and edema. No severe side effect was present. Large area of lesion (>8 cm(2)), vagina involved and unemployment were associated with the failure of single-period treatment while pain symptom was a protective factor of effectiveness. Age, marital status, symptom-free and vaginal involvement were not related with outcome. A prediction model was established as follows: Logit (P(0)) = -1.511+1.573X(1)+1.679X(2)+3.254X(3)-1.685X(4) (X(1)-X(4) representing area of lesion > 8 cm(2), vaginal involvement, unemployment and pain symptom respectively). The optimal cutoff value of P(0) was 0.35 with AUC ROC of 0.816 (P < 0.01). The sensitivity, specificity, positive predictive value and negative predictive value of model were 58.6%, 91.6%, 60.7% and 90.9% respectively.

CO(2) laser is effective and safe therapy for vulvar condylomata acuminata. A prediction model has been proposed to predict the outcome of single-period CO(2) laser therapy in initially diagnosed patients. It may guide clinical decision-making.