Prognostic Relationship Between the ABO Blood Groups and Metastatic Gastric Cancer

Aim: Gastric cancer is one of the most common malignant tumors of the digestive system and has a poor prognosis. Since recurrence and distant metastasis are common in gastric cancer, it is important to use practical and reliable prognostic parameters. In this study, the prognostic relationship between the ABO blood groups and metastatic gastric cancer was investigated. Method and Material: Data were collected by retrospectively scanning the files of 225 patients who were followed up with the diagnosis of metastatic gastric cancer in 2010-2022. The patients' demographic data (age, gender), tumor histopathology, tumor location, and ABO and Rh blood groups were evaluated. Results: Of the patients, 138 (61.3%) were male and 87 (38.7%) were female. According to the distribution of the ABO system, blood group A was present in 109 (48.4%) patients, B in 33 (14.7%), AB in 20 (8.9%), and O in 63 (28%). Signet ring cell carcinoma, antrum tumor localization, and distant metastasis were more common in blood groups A and O. According to both the univariate and multivariate analyses, overall survival (OS) was statistically worse in patients with signet ring cell carcinoma and peritoneal metastasis (p < 0.05). The OS rate was the worst in blood group A and best in blood groups AB and B. Conclusion: In this study, blood group A presented as both a risk factor and a poor prognostic factor in the development of metastatic gastric cancer. In addition, signet ring cell histopathology and presence of metastasis were found to be more common in patients with blood group A and associated with a poor prognosis. Blood groups are inexpensive, easily available, and reliable parameters that can provide an idea about both prognosis and survival in gastric cancer. Therefore, they can serve as a guide for clinicians in the follow-up and evaluation of the prognosis of these patients.