ABO and Rh blood groups as factors increase breast cancer risk, modified by age and sex

Cancer is one of the leading causes of death worldwide, a malignant disease that occurs due to abnormal growth of some body cells and their spread to other parts of the body. It is divided into types according to the affected organ (colon, liver, lung, bone cancer... etc.). One of the most common types, especially among women, is breast cancer. Many risk factors associated with the likelihood of many researchers, and some research has shown a link between blood type and increased risk. Blood is divided into four groups; A, B, AB and O Based on the presence or absence of two types of antigens, which are anti A and anti B. This study aimed to investigate the association between blood type and Rh factor with increased risk of breast, as well as to determine the relationship between age, sex, and geographic distribution of breast cancer cases in the study area. The study was conducted on patients attending the African Institute for Cancer Treatment in Sabratha, reviewing data from 125 cases diagnosed in 2020-2021 at the center, and comparing the study sample with a control group of 100 blood donors without cancer. The study lasted from April 2022 to May of the same year. Results showed that there was strong correlation of blood type with positive rate in breast cancer. The most frequent patient population blood type was A+ (39.3%), followed by O+. The study also showed a correlation between sex and age, with 97.6% of the patients being females especially among those who are aged 40-50 years. The study revealed that IR were higher in northern coastal areas notably Zawiya (35.2%).than those in the south (5.6%). Studies in the past have delivered mixed findings on this relation. Based on the study, it could be inferred that blood type, sex and age increase the chances of having breast cancer. It suggested to conduct more precise investigation with larger population and monitoring of A+ blood groups especially female individuals. Keywords: breast cancer, blood type, Rh factor.