Serum selenium and thromboxane in patients with gynaecological cancer

To explore the relationships between the antioxidant selenium and pro-aggregatory thromboxane A2 in patients with gynaecological cancer, we measured the serum concentrations of selenium and the production of thromboxane B2 (TxB2, a stable metabolite of thromboxane A2) by the aggregating platelets in patients with endometrial (n = 35), ovarian (n = 30) and cervical cancer (n = 25), and in 32 control women. The selenium concentration in endometrial (1.14 +/- 0.04 mumol/l; mean +/- SE), ovarian (0.96 +/- 0.04 mumol/l) and cervical cancer (0.97 +/- 0.06 mumol/l) was significantly lower than in control subjects (1.26 +/- 0.03 mumol/l). The release of TxB2 into serum during spontaneous clotting of the blood was significantly increased in ovarian cancer (229.2 +/- 15.9 ng/ml), decreased in endometrial cancer (142.6 +/- 12.4 ng/ml) and normal in cervical cancer (185.9 +/- 14.8 ng/ml) as compared with control subjects (185.9 +/- 11.9 ng/ml). The levels of selenium and TxB2 did not correlate with each other in the whole series or in any subgroup. Thus, selenium does not seem to be an important determinant in the biosynthesis of TxB2 in patients with gynaecological malignancy.