Nickan Research Institute Immunopathologia Persa 2423-8015 11 2 2025 07 01 The association between systemic immune-inflammation index and risk of prostate carcinoma; a systematic review and meta-analysis e43810 e43810 10.34172/ipp.2025.43810 EN Atefeh Nourmohammadi https://orcid.org/0009-0004-6887-8001 Sajad Ataei Azimi https://orcid.org/0000-0003-4542-9647 Radhwan Abdul Kareem Sarah Qutaiba Badraldeen https://orcid.org/0009-0001-1840-2599 Rasoul Jafari Arismani https://orcid.org/0000-0001-7440-0507 Roozbeh Roohinezhad https://orcid.org/0000-0002-0866-2047 Hossein Pourmasomi https://orcid.org/0000-0002-8662-3529 Armin Attar https://orcid.org/0009-0006-0946-0259 Seyed Sohrab Vahdati https://orcid.org/0009-0003-1722-158X Journal Article 10.34172/ipp.2025.43810 2024 10 12 2025 01 30 Introduction: Prostate carcinoma is the second most common cancer in the world, and the association between the systemic immune inflammation (SII) index and prostate cancer is not clear. Objectives: The present study aimed to investigate the relationship between the SII index and prostate carcinoma using systematic review and meta-analysis methods. Materials and Methods: Databases ProQuest, Embase, PubMed, Web of Science, Cochrane, and Google Scholar Search Engine were used to find articles published by November 10, 2024. There was no limitation for the time or location of the studies in the search for resources. Data was analyzed using STATA software version 14, and tests with P values<0.05 were considered statistically significant. Results: In general, high SII index levels increased the risk of prostate carcinoma (Odds ratio [OR]: 1.44; 95% CI: 1.22, 1.70). High SII index levels in the United States and cross-sectional studies increased the risk of prostate cancer by 44 percent; however, there was no significant relationship between the SII index and prostatic neoplasms in China or case-control (OR: 1.27; 95% CI: 0.47, 3.43) studies. Furthermore, the increase of the SII index in the middle one-third (OR: 1.35; 95% CI: 1.11, 1.64), upper one-third (OR: 1.57; 95% CI: 1.16, 2.10), and the fourth quartile (OR: 2.17; 95% CI: 1.44, 3.27) increased in the risk of prostate carcinoma. However, in the second quartile (OR: 0.91; 95% CI: 0.53, 1.55) and third quartile (OR: 1.26; 95% CI: 0.59, 2.70), there was no significant association between the SII index and the risk of prostatic neoplasms. High neutrophil-to-lymphocyte ratio (NLR) levels increased the risk of prostate carcinoma (OR: 1.50; 95% CI: 1.24, 1.82), but there was no statistically significant relationship between total prostate specific antigen and prostate cancer (OR: 1; 95% CI: 0.72, 1.39). Conclusion: High SII index levels and high NLR levels increased the risk of prostate carcinoma by 44% and 50%, respectively, and those with elevated SII and NLR were at higher risk. Registration: This study has been compiled based on the PRISMA checklist, and its protocol was registered on the PROSPERO (ID: CRD42024616273) and Research Registry (UIN: reviewregistry1921) websites.