Abstract
Background Previous research on connection between the ABO blood group and bladder cancer has
been based on determining the ABO phenotype. This specific research is extended to
the molecular level, providing more information about particular ABO alleles.
Aim To investigate the impact of the ABO blood group genotype or phenotype as a risk
factor for urinary bladder cancer.
Materials and Methods In the case–control study, we included 74 patients who underwent surgery for a urinary
bladder tumor at the Urology Clinic, Clinical Hospital Centre Zagreb, in 2021 and
2022. The control group comprised 142 asymptomatic and healthy blood donors. ABO genotyping
to five basic alleles was done using a polymerase chain reaction with sequence-specific
primers. We compared ABO phenotypes, genotypes, and alleles between patients and the
healthy controls and investigated their distribution according to the clinical and
histological stage and recurrence rate.
Results No statistically significant difference was found among the groups, nor for the observed
disease stages in terms of the phenotype and genotype. At the allele level, the results
show a significantly lower proportion of malignancy in O1 (p < 0.001), A1 (p < 0.001), and B (p = 0.013), and a lower proportion of metastatic disease in A2 (0%, p = 0.024). We also found significantly higher proportions of high-grade tumors in
patients with O1 (71.4%, p < 0.001), A1 (70.1%, p = 0.019), of nonmuscle invasive tumors in patients with O1 (55.1%, p < 0.001), O2 (100%, p = 0.045), and recurrent tumors in patients with O1 (70.2%, p < 0.001) and A1 (74.2%, p = 0.007) alleles.
Conclusion We did not find an association between the ABO blood group genotype or phenotype
as a genetic risk factor for urinary bladder cancer. However, an analysis at the allelic
level revealed a statistically significant association between certain alleles of
the ABO blood group system and urinary bladder tumors, clinical or histological stage,
and recurrence rate, respectively.
Keywords
ABO blood groups - urinary bladder cancer - ABO phenotype - ABO genotype - ABO allele
- case–control study
