High and/or Non-Decreased Systemic Inflammatory Index During Treatment Indicates Poor Prognosis in Patients with Esophageal Cancer

Original Article
Introduction: The initial high systemic inflammatory index (SII), which is calculated as platelets × (neutrophils / lymphocytes), indicates a poor prognosis in patients with various malignant tumors, but its value after treatment in esophageal cancer is not well described. Methods: The prognostic value of the perioperative SII was evaluated in 103 esophageal cancer patients treated by radical esophagectomy. Fifty-nine of the patients received neoadjuvant chemotherapy (NAC); 44 received surgery only. The prognostic value of the SII was evaluated at each stage of the treatment. The impact of clinicopathological factors on the SII and prognosis was also evaluated after stratifying patients by treatment with surgery and NAC or surgery only. Results: Pre-treatment SII was not associated with prognosis, but pre-operative SII (p = 0.11), post-operative SII (p = 0.07), and post-NAC SII (p < 0.05) were associated with prognosis. A decrease in the SII during treatment was also associated with a good prognosis. A high SII before NAC was significantly associated with a decrease of SII during treatment (p < 0.05). Conclusions: A high or non-decreased SII after treatment of esophageal cancer was a poor prognostic indicator. The prognosis of patients with high SSIs might be improved by NAC.