ABO blood types and head and neck cancer: a systematic review with meta-analysis of observational studies

ObjectivesThis research aims to explore the correlation between ABO blood groups and neoplasms in the head and neck region, specifically investigating the susceptibility of different blood groups to tumours.DesignSystematic review and meta-analysis.Data sourcesCNKI, WANFANG DATA, PubMed, Web of Science and Embase databases were systematically searched from inception to January 2024.Eligibility criteriaAll studies of ABO blood type and head and neck tumours will be included in this study.Data extraction and synthesisA systematic literature review was performed using digital platforms on CNKI, WANFANG DATA, PubMed, Web of Science and Embase databases, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for meta-analysis. Two authors independently extracted the data and assessed the quality of included studies. The Newcastle-Ottawa Scale was used to assess the quality of the included studies. Comparisons were made between blood types A, B, AB and their combined group versus O, along with subgroup analyses. Systematic analysis was performed by using Review Manager V.5.4 and Stata V.18 statistical software.Results30 articles were included, involving 737 506 subjects, among which 21 382 were patients with head and neck tumours. The overall analysis indicated a significant association between type AB blood (OR 0.762, 95% CI 0.637 to 0.910) and a reduced risk of head and neck tumours. In the Caucasoid race, type A blood is significantly linked to an elevated likelihood of head and neck tumours (OR 1.353, 95% CI 1.076 to 1.702), while in the Mongoloid race, type AB blood is significantly linked to a reduced likelihood of developing tumours in the head and neck area (OR= 0.732, 95% CI 0.588 to 0.910). No significant associations were found in the subgroup analysis by gender. Regarding different types of cancer, type A blood is significantly associated with an increased risk of salivary gland tumours (OR 1.338, 95% CI 1.075 to 1.665), and type AB blood is significantly linked to a lower likelihood of nasopharyngeal carcinoma (OR 0.590, 95% CI 0.429 to 0.812).ConclusionA correlation exists between ABO blood groups and tumours in the head and neck region. However, the link between blood type and head and neck tumours requires further confirmation through more prospective studies.PROSPERO registration numberCRD42024510176.