Can ABO Blood Type Determine Small Cell Lung Cancer Risk?

Introduction: Many cases of small cell lung cancer (SCLC) are diagnosed at an advanced stage, which remains the biggest barrier to improving survival. Identifying high-risk patients for early diagnosis and treatment is crucial. ABO blood groups and Rh factor may influence the risk of SCLC. Materials and Methods: The medical records of 118 SCLC patients with confirmed ABO/Rh blood types were retrospectively reviewed. A control group was selected from healthy blood donors of the Turkish Red Crescent. The distribution of ABO/Rh blood groups between the patients and controls was compared. Results: The median age was 66 years (range: 39-87). A clear male predominance was observed (87.3% vs. 12.7%). Significant differences were found between patients and controls in terms of non-A vs. A (P=0.04391) and non-O vs. O (P=0.006289). Additionally, there was no significant difference between the patients and controls in the general distribution of ABO blood groups (P=0.1747). There were no statistically significant differences in terms of gender, age, or smoking status between the blood groups. Conclusion: In the study population, ABO blood groups were associated with SCLC. Having blood group A was found to reduce the risk of SCLC, whereas having blood group O increased the risk. This study is the largest to compare ABO blood groups with SCLC patient data in the literature. However, further prospective studies are required to define how ABO blood groups may influence the risk of SCLC.