Predictive values of serum squamous cell carcinoma antigen and its changes in neoadjuvant chemotherapy sensitivity of cervical squamous cell carcinoma

Abstract

Objective To explore the changes of serum squamous cell carcinoma antigen (SCC-Ag) before and after neoadjuvant chemotherapy (NACT) in cervical squamous cell carcinoma (SCC), and to assess its predictive values of NACT sensitivity in cervical SCC. Methods A total of 68 patients who underwent NACT before surgery and were diagnosed as cervical SCC by postoperative biopsy from January 2009 to January 2017 in the Second Hospital of Shanxi Medical University were selected as research subjects. The efficacy of NACT in treatment of patients with cervical SCC were analyzed. Serum SCC-Ag values and its positive rates before and after NACT were compared by paired-samples t test and paired-chi-square test, respectively. The area under curve (AUC) of receiver operating characteristic (ROC) was used to analyze the predictive values of serum SCC-Ag value before NACT and changes of serum SCC-Ag values before and after NACT in NACT sensitivity of cervical SCC. Multiple unconditional logistic regression analysis was used to analyze the influencing factors of NACT efficacy in cervical SCC. Chi-square test or Fisher′s exact test was used to analyze the relationship between the positive rate of serum SCC-Ag before and after NACT in cervical SCC patients and their clinicopathological characteristics. Independent-samples t test was used to compare serum SCC-Ag values in cervical SCC patients with recurrent and non-recurrent before receiving NACT. This study met the requirements of the World Medical Association Declaration of Helsinki revised in 2013. And every subject signed an informed consent form. Results ①The efficacy of NACT in treatment of patients with cervical SCC was 75.0% (51/68). ②The value and positive rate of serum SCC-Ag after NACT in 68 patients with cervical SCC were (2.9±1.6) ng/mL and 45.6% (31/68), respectively, which were significantly lower than those before NACT (5.1±1.7) ng/mL and 91.2% (62/68), and both the differences were statistically significant (t=7.991, P<0.001; χ2=32.682, P<0.001). ③The ROC-AUC of serum SCC-Ag value before NACT and changes of serum SCC-Ag values before and after NACT in predicting the efficacy of NACT for cervical SCC were 0.839 (95%CI: 0.717-0.965, P<0.001) and 1.000 (95%CI: 1.000-1.000, P<0.001), respectively, with the optimal cut-off values of 3.0 ng/mL and 0.6 ng/mL, respectively. ④The results of multiple unconditional logistic regression analysis of influencing factors of NACT efficacy in cervical SCC showed that the serum SCC-Ag value before NACT and changes of serum SCC-Ag values before and after NACT both were independent predictors of NACT sensitivity of cervical SCC (OR=0.365, 95%CI: 0.224-0.608, P<0.001; OR=0.984, 95%CI: 0.899-0.998, P<0.001). ⑤Among 68 patients with cervical SCC in this study, the positive rate of serum SCC-Ag before NACT in patients with vascular metastasis was higher than those without vessel metastasis, and the positive rates of serum SCC-Ag after NACT in patients with lymph node metastasis, vascular metastasis, International Federation of Gynecology and Obstetrics (FIGO) stage ⅡA2 were significantly higher than those without lymph node metastasis, vascular metastasis, and stage ⅠB2, respectively, and all the differences were statistically significant (P=0.007, P<0.001, P =0.035, P<0.001). ⑥Among 68 patients with cervical SCC in this study, 13 cases relapsed, with a recurrence rate of 19.1% (13/68). The serum SCC-Ag value before NACT in patients with recurrence was (7.1±1.1) ng/mL, which was higher than that of those without recurrence (4.7±1.5) ng/mL, and the difference was statistically significant (t=5.253, P<0.001). Conclusions Whether serum SCC-Ag value and its changes can be used as effective predictors of NACT sensitivity of cervical SCC, and whether they can be used as detection indexes of cervical SCC recurrence or not, it still remains to be further confirmed by large-sample, multi-center, and randomized controlled studies as the sample size included in this study is relatively small. Key words: Uterine cervical neoplasms; Carcinoma, squamous cell; Antigens, neoplasm; Squamous cell carcinoma antigen; Antineoplastic combined chemotherapy protocols; Sensitivity and specificity; Women