Elevation of serum CA 19-9 in parallel with HbA 1c in a diabetic female with the Lewis(a + b −) blood group

Abstract

We report a 66-yr-old diabetic female with her serum CA 19-9 levels elevated in parallel with her hemoglobin A 1c (HbA 1c) levels. She was initially suspected of having pancreatic cancer, but this was later proved to be false. Her serum CA 19-9 levels varied between 58 and 235 U/ml over a 3-yr period, and correlated significantly ( r = 0.68, P < 0.01) with her HbA 1c levels (7.2–13.3%). She belonged to the Lewis (a + b −) blood group. Serum CA 19-9 levels were also assessed in 73 diabetic patients (36 males and 37 females) in relation to sex and Lewis blood group. The mean level of serum CA 19-9 was higher in females than in males in each Lewis blood group, and it was the highest in patients with Le(a + b −) and the lowest in Le(a − b −). Patients with a higher level of HbA 1c showed a higher level of serum CA 19-9 in Le(a + b −), but patients with Le (a − b −) showed a low level of serum CA 19-9 irrespective of HbA 1c level. Patients with Le(a − b +) appeared to intermediate between the patients with Le(a + b −) Le(a − b −). Thus, the elevation of serum CA 19-9 level due to hyperglycemia was indicated to be affected by sex as well as Lewis blood group. The biosynthesis of CA 19-9 seemed to be accelerated in hyperglycemic diabetic patients, especially in females. Consequently, it was considered that the present case was a diabetic female with the Le(a + b −) blood group, which led to showing a relatively high level of serum CA 19-9 correlated with HbA 1c level.