Mucin-like carcinoma-associated antigen (MCA) during normal pregnancy

To assess the usefulness of Mucin-like carcinoma-associated antigen (MCA) in monitoring pregnant patients with breast cancer.

Maternal serum (MS) and amniotic fluid (AF) antigen values were measured by an enzyme immunoassay in 30 pregnant women during the second trimester, in 28 during the third and in 26 at parturition. Sera only from 26 women in the first trimester and from 26 healthy, non-pregnant women (controls) were also analyzed.

Maternal serum MCA concentrations increased significantly with gestational age (p<0.0001). The frequency of elevated serum values was 5% in the first, 35% in the second and 100% in the third trimester and at parturition. Antigen values in AF were markedly higher than those in MS (p<0.0001) and increased also significantly with advancing gestation (p<0.0001). A strong correlation was observed between MS and AF antigen values (r=0.77, p<0.0001). Maternal serum values at parturition were dependent on the mode of delivery, being higher in the cases who delivered vaginally, compared to those delivered by elective caesarean section (p<0.006).

Our data suggest that pregnancy affects significantly maternal serum MCA. Consequently, MCA seems to be a non-reliable marker in monitoring pregnant patients.