Is ABO blood group a risk or prognostic factor for patients with endometrioid endometrial cancer? A retrospective analysis in Germany

BACKGROUND: A relationship is known to exist between gastric and pancreatic cancers and ABO antigens, caused by various immune modulations related to the ABO blood group of the patient. A similar relationship with regard to gynaecological cancers remains controversial. MATERIALS AND METHODS: Patients who underwent surgery for endometrioid endometrial cancer in International Federation of Gynaecology and Obstetrics (FIGO) stage I, II, III or IV from 2006 to 2018 were identified. The research explored the existence of a relationship between the patients' blood group or Rhesus factor and the incidence of endometrial cancer, grade (G1, G2, G3), FIGO stage, nodal status, recurrence, menopausal status, parity, and body mass index. Statistical methods such as the chi-square test, analysis of variance and the Scheffé post-hoc test were used. RESULTS: Two hundred and two patients with endometrioid endometrial cancer were included: 96 had blood group A, 19 blood group B, 75 blood group 0, and 12 had blood group AB. This distribution corresponds to the general blood group distribution in Germany. The vast majority of the dependent variables, such as grade, FIGO stage, nodal status or recurrence were not significantly associated with ABO blood group or Rhesus factor status. The relative frequencies of G1 and G3 endometrial cancers with respect to blood group were similar. Menopausal status, parity, and body mass index were not related to more advanced FIGO stages at initial diagnosis or to ABO blood group. DISCUSSION: Blood group screening would probably not be helpful in the diagnosis of endometrioid endometrial carcinomas in early stages compared to the current gold standard. Furthermore, a specific blood group does not increase either the risk of recurrence or the risk of a dedifferentiated type of endometrial carcinoma.