Introduction: Triple-negative breast cancer (TNBC) has a poorer prognosis; the factors that contribute to this remain unclear. We hypothesized that TNBC is associated with ABO blood type/Rh factors that account for differences in survival.
Methods: We identified 468 patients with stage I-III TNBC [estrogen receptor (ER)-negative, progesterone receptor (PR)-negative, and HER2 nonamplified]. Patient/tumor characteristics, treatments, and outcomes were obtained. Data were examined for associations with specific ABO blood type/Rh factors. Descriptive statistics and χ (2) analysis were utilized for data summary and comparisons.
Results: Of 468 TNBC patients, 283 had known ABO blood type [122 (43 %) O, 108 (38 %) A, 39 (14 %) B, and 14 (5 %) AB] and Rh factor [253 (89 %) positive and 30 (11 %) negative]. Mean patient age was 53.7 ± 12.5 years, and median follow-up was 30.2 ± 20.5 months. The incidence of each ABO blood type/Rh factor in our TNBC cohort was not different from the general population or a cohort of ER-positive breast cancers (P > 0.05). Compared with patients with blood type O, there was no difference in breast cancer-specific mortality for type A [hazard ratio (HR) 0.906; 95 % confidence interval (CI) 0.554-1.481], type B (HR 1.534; 95 % CI 0.792-2.972), or type AB (HR 0.488; 95 % CI 0.113-2.106). Compared with women with negative Rh, there was no difference in breast cancer-specific mortality for women with positive Rh (HR 1.161; 95 % CI 0.568-2.374).
Conclusions: TNBC was not associated with a specific ABO blood type or Rh factor. Our results failed to demonstrate an association between ABO blood type/Rh factor and breast cancer mortality in patients with TNBC.