Recurrence of prostate cancer is significantly lower in men with blood group O

Prostate cancer is the most common cancer in men, with huge differences in incidence across Europe. For localized prostate cancer the current "gold standard" treatment is Radical Prostatectomy (RP). However despite apparently successful surgery, approximately 30% of patients experience biochemical recurrence (shown by a rising level of Prostate Specific Antigen, PSA) during long-term follow-up.

This new study, from a team led by Dr Yoshio Ohno of Tokyo Medical University, has shown that patients with blood group O had a significantly decreased risk of cancer recurrence after radical prostatectomy (RP).

The team looked at 555 patients with localized prostate cancer who underwent RP between 2004 and 2010. After following the patients for an average of 52 months, they found that patients with blood group O were 35% less likely to have a recurrence of prostate cancer than patient who had blood group A.

Dr Ohno commented: "This is the first time that anyone has shown that prostate cancer recurrence can vary with blood group. Of course we need bigger studies to confirm the effect and also to see what practical application the finding might have. For example, we know that there are wide racial and geographical variations in the distribution of the ABO blood groups, and we need to be sure that this effect is significant in other groups.

As yet, we don't know why the risks vary with blood group, but this work may guide us towards new avenues of molecular research on prostate cancer progression. We need to consider what these results means in practical, clinical terms. For example, should we be counselling people with certain blood groups that they have a greater or lesser chance of recurrence, and should these risk factors be built into decisions on treatment?"

In the past, variation in ABO blood groups have been found to be associated with different risk of developing certain cancers, such as gastric and pancreatic cancers, and recently it has also been shown that prostate cancer incidence varies with blood group2.

Commenting, EAU General Secretary, Professor Per-Anders Abrahamsson (Malmo) said: "This is an interesting first finding. There is great geographical variation the incidence of prostate cancer, so there are obviously strong genetic factors at play. Blood groups have already been shown to be associated with prostate cancer incidence, not it looks like they might be associated with treatment outcomes as well."