Predictive value of the systemic immune-inflammation index for the efficacy of neoadjuvant chemotherapy and prognosis in patients with stage III ovarian cancer—a retrospective cohort study

BACKGROUND: The systemic immune-inflammation index (SII) has been proven to be related to the prognoses of multiple malignant tumors. However, there are still few studies on the relationship between the SII and the effect of neoadjuvant chemotherapy in patients with ovarian cancer. It is of great significance to predict the efficacy of neoadjuvant chemotherapy in patients with ovarian cancer. Our study was aimed at determining the predictive value of the SII for the efficacy of neoadjuvant chemotherapy and prognosis in patients with stage III ovarian cancer. METHODS: A total of 102 patients with stage III ovarian cancer treated in Tongji Hospital of Tongji University from January 2017 to January 2019 were retrospectively collected. According to the level of the SII before neoadjuvant chemotherapy, patients were divided into the high SII group and low SII group. We compared the effect of neoadjuvant chemotherapy between the 2 groups, and observed the progression-free survival and mortality of patients in the 2 groups after 3 years follow-up. RESULTS: Compared with patients in the low SII group, the complete response rate of patients in the high SII group decreased significantly after neoadjuvant chemotherapy (13.73% vs. 45.10%, P=0.001), and the progressive disease rate increased (19.61% vs. 1.96%, P=0.011). The SII had certain value in predicting the inefficacy of neoadjuvant chemotherapy in patients with stage III ovarian cancer, and the area under the curve was 0.655 (95% CI: 0.548–0.762, P=0.007). The progression-free survival of patients in the high SII group was shorter than that of patients in the low SII group (P<0.001), and the overall survival rate of patients in the high SII group was lower (47.06% vs. 70.59%, P=0.016). The SII had predicting value for the postoperative death of ovarian cancer patients after neoadjuvant chemotherapy, and the area under the curve was 0.646 (95% CI: 0.537–0.756, P=0.012). Multivariate regression analysis showed that higher SII was a risk factor for death in ovarian cancer patients after neoadjuvant chemotherapy (OR: 2.700, P=0.017). CONCLUSIONS: A high SII was a predictor of inefficacy of neoadjuvant chemotherapy in patients with stage III ovarian cancer and was related to poor prognosis.