[Urinary gonadotropin fragment measurement in the monitoring of trophoblastic disease].

Urinary gonadotropin fragment (UGF) is a small peptide which is present in the urine of pregnant women and of women with trophoblastic diseases as well as with certain nontrophoblastic malignancies. 275 samples each of urine and blood from 46 patients with trophoblastic diseases were taken for UGF and hCG measurements and compared. 24 samples from 12 healthy, nonpregnant women were taken as control. Cut-off values of UGF and hCG used for measuring the sensitivity of trophoblastic diseases were respectively > 0.2 microgram/L and above 20 micrograms/L. It was found that 64.0% of the urine samples gave UGF values > 0.2 microgram/L and 66.5% of the blood samples showed hCG levels above 20 micrograms/L (P > 0.1). No false-positive rate was observed in the control group. However, among patients who were found to have low or negative hCG values, 57.6% showed positive UGF levels. These findings suggest that in patients with positive levels of both UGF and hCG, the UGF measurement may not be necessary. But for patients with low or negative blood hCG values, certain percentage of urine UGF could still be detected.