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

Abstract

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.