Development of a nomogram for predicting survival of breast cancer patients with neoadjuvant chemotherapy: a dynamic analysis for systemic inflammation response index

Background: The systemic inflammation response index (SIRI) has been reported to associate with survival outcomes in breast cancer patients. However, the effects of baseline SIRI and SIRI change after neoadjuvant chemotherapy (NACT) have not been thoroughly investigated. This study aimed to evaluate the role of baseline SIRI and SIRI change after NACT in predicting survival outcomes, and establish a nomogram based on SIRI. Methods: A total of 260 patients diagnosed with breast cancer who received NACT between January 2014 and December 2018 at our hospital were included. The clinical data were retrospectively collected from the medical records management system. The associations between clinicopathological factors and baseline SIRI, pathological complete response (pCR) were analyzed by Student's t -test, Chi -squared test, or Fisher's exact test. The association between clinicopathological factors and disease -free survival (DFS) was evaluated by univariate and multivariate Cox regression analyses. Results: Patients with a tumor -node -metastasis (TNM) stage of I, II, and III were 1.9%, 20.0%, and 78.1% respectively. The median follow-up time was 40 months, and 74 (28.5%) patients had cancer recurrence during the follow-up. Both in the univariate and multivariate analysis, Ki-67, pCR, and baseline SIRI were independent factors associated with DFS. Patients with low baseline SIRI had prolonged DFS compared with those with high baseline SIRI [<= 1.6x109 vs. >1.6x109, hazard ratio (HR) =0.545, P=0.028]. In addition, SIRI change after NACT was also an independent factor associated with DFS, and patients with minor SIRI change had longer DFS than patients with major SIRI change (>50% or <-30% vs. <= 50% and >=-30%, HR =1.721, P=0.037). Nomograms were established based on Ki-67, pCR, and baseline SIRI or SIRI change after NACT with a concordance index of 0.665 and 0.663 respectively, and the nomogram provided a convenient tool for predicting the probability of DFS. Conclusions: The baseline SIRI and SIRI change after NACT could act as potential biomarkers for predicting survival outcomes in breast cancer. Besides, the nomogram with SIRI is an economic and convenient tool for predicting DFS. Larger prospective studies are needed to verify the results.