The prognostic value of squamous cell carcinoma antigen for predicting tumor recurrence in cervical squamous cell carcinoma patients

OBJECTIVE: The aim of this study was to evaluate the prognostic value of squamous cell carcinoma antigen (SCC-Ag) and the optimal cut-off value for predicting recurrence in cervical squamous cell carcinoma patients with complete remission after primary treatment. METHODS: We reviewed the records of 783 cervical squamous cell cancer patients who underwent primary therapy and showed complete remission at our institution between January 2000 and April 2014. A receiver operating characteristic curve was used to determine the optimal SCC-Ag threshold to predict recurrence. Cox regression model for disease free survival was used to assess differences in outcome. RESULTS: The median follow-up period was 41.2 months, and 154 patients (19.7%) had recurrent disease. The median pretreatment and posttreatment SCC-Ag level was 2.6 ng/mL (range, 0.1 to 532.0 ng/mL) and 0.7 ng/mL (range, 0.0 to 46.8 ng/mL), respectively. Both pretreatment and posttreatment SCC-Ag levels were higher in the recurrence group (P=0.017 and P=0.039). Optimal cut-off value of pretreatment and posttreatment SCC-Ag for predicting recurrence was 1.86 ng/mL (area under the curve, 0.663; P=0.000), and 0.9 ng/mL (area under the curve, 0.581; P=0.002), respectively. In the multivariate Cox regression model, pretreatment SCC-Ag >1.86 ng/mL (odds ratio, 2.11; 95% confidence interval, 1.38 to 3.22; P=0.001) and posttreatment SCC-Ag >0.9 ng/mL (odds ratio, 1.64; 95% confidence interval, 1.18 to 2.28; P=0.003) were significantly associated with poor disease free survival. CONCLUSION: Patients with pretreatment SCC-Ag >1.86 ng/mL or posttreatment SCC-Ag >0.9 ng/mL should be considered at high risk for cancer recurrence after complete remission, and therefore, closer surveillance is needed.