Systemic immune-inflammation index, SII, for prognosis of elderly patients with newly diagnosed tumors.

Background: Cancer in the elderly has become a common problem due in part to the increase in life expectancy. Compared to younger counterparts, the biological characteristics of tumors and their responsiveness to therapy may differ in elderly patients, and the elderly also can have a decreased tolerance to anticancer therapy. In addition, there is less evidence from clinical trials to guide physicians in treating aged patients with solid tumors. Thus, we often face a dilemma as to how actively to treat these patients and it would be highly useful to have a simple and powerful indicator of their prognosis. In this paper we evaluated the predictive value of the Systemic Immune-inflammation Index, SII, in determining the one-year survival and tumor differentiation status in elderly patients with newly diagnosed solid tumors.

Results: A high SII > 390×109 cells/L was correlated with poor tumor differentiation (χ2 = 9.791, P = 0.002) and poor one-year survival (χ2 = 7.658, P = 0.006). Patients with low SII had improved survival and better tumor differentiation (Stage I-II). The SII was not associated with Ki-67 expression.

Materials and Methods: Data from 119 patients, 70 to 89 years of age with newly diagnosed solid tumors in 2014 were retrospectively analyzed. The patients were divided into two groups according to age: (1) 70-75 years of age and (2) over 75 years of age. We calculated SII from the equation, SII = P x N/L, where P, N and L are the preoperative peripheral blood platelet, neutrophil and lymphocyte counts per liter respectively. The optimum cutoff point for SII for a favorable prognosis was determined to be 390×109 cells/L. For evaluation of SII as a prognostic indicator, the patients were divided into high SII (> 390×109 cells/L) and low SII (≤ 390×109 cells/L) groups. Individual values were used to determine the relationship between SII and one-year survival, tumor differentiation and Ki-67 expression in the two age groups.

Conclusions: SII was a robust indicator of tumor differentiation and one-year survival in elderly patients with newly diagnosed solid tumors. Patients in the high SII group showed poor tumor differentiation and poor prognosis compared to patients with a low SII score.