Prognostic and clinicopathological significance of systemic immune-inflammation index in colorectal cancer: a meta-analysis

Meilian Dong; Yonggang Shi; Jing Yang; Quanbo Zhou; Yugui Lian; Dan Wang; Taoran Ma; Yue Zhang; Yin Mi; Xiaobin Gu; Ruitai Fan

doi:10.1177/1758835920937425

Prognostic and clinicopathological significance of systemic immune-inflammation index in colorectal cancer: a meta-analysis

Ther Adv Med Oncol. 2020 Jul 11:12:1758835920937425. doi: 10.1177/1758835920937425. eCollection 2020.

Authors

Meilian Dong¹, Yonggang Shi¹, Jing Yang¹, Quanbo Zhou², Yugui Lian², Dan Wang³, Taoran Ma⁴, Yue Zhang¹, Yin Mi¹, Xiaobin Gu⁵, Ruitai Fan⁵

Affiliations

¹ Department of Radiation Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, People's Republic of China.
² Department of Colorectal Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, People's Republic of China.
³ Department of Biotherapy Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, People's Republic of China.
⁴ Department of Education Section, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, People's Republic of China.
⁵ Department of Radiation Oncology, The First Affiliated Hospital of Zhengzhou University, No. 1 Jianshe East Rd, Zhengzhou, Henan 450000, People's Republic of China.

Abstract

Background: Previous studies on the systemic immune-inflammation index (SII), which is based on platelet, neutrophil and lymphocyte counts, as a prognostic marker in patients with colorectal cancer (CRC) yielded inconsistent results. The aim of this study was to evaluate the prognostic and clinicopathological role of SII in CRC via meta-analysis.

Methods: A comprehensive literature survey was performed on PubMed, Web of Science, Embase and the Cochrane Library databases to include studies published up to 6 April 2020. Pooled hazard ratios (HRs) and odds ratios (ORs) with 95% confidence intervals (CIs) were computed to estimate the prognostic and clinicopathological value of SII in CRC.

Results: A total of 12 studies published between 2016 and 2019 were included in our meta-analysis. The combined analysis showed that high SII levels were significantly associated with worse overall survival (OS; HR = 1.61, 95% CI = 1.21-2.13, p = 0.001) and progression-free survival (HR = 1.74, 95% CI = 1.26-2.39, p = 0.001) in CRC. Moreover, elevated SII was also correlated with poor tumor differentiation (OR = 1.60, 95% CI = 1.27-2.02, p < 0.001), presence of distant metastasis (OR = 2.27, 95% CI = 1.10-4.67, p = 0.026), ECOG PS of 1-2 (OR = 1.98, 95% CI = 1.39-2.84, p < 0.001) and tumor size ⩾5 cm (OR = 1.49, 95% CI = 1.18-1.88, p = 0.001). However, high SII was not significantly associated with sex, tumor location, lymph node metastasis, or age in patients with CRC.

Conclusion: Our meta-analysis indicated that high SII levels predicted poor prognosis in CRC. In addition, an elevated SII was also associated with clinical factors, implying higher malignancy of the disease.

Keywords: colorectal cancer; meta-analysis; prognosis; risk factors; systemic immune-inflammation index.