The clinical significance of serum sialyl Tn antigen levels in patients with gynecologic tumors

In order to estimate the clinical significance of sialyl Tn (STN) antigen, the antigen was measured with an "STN" Otsuka Kit in sera from patients with various gynecologic tumors and healthy women. The antigen in ovarian fluid was also determined. Furthermore, the amount of serum STN antigen was serially checked in the patients with increased serum STN to evaluate the correlation between serum STN and the response to treatment. Results obtained were as follows. 1) Among the patients with uterine myoma, uterine malignancies and benign ovarian tumors, the incidence of increased serum STN antigen was low. 2) Among the patients with ovarian malignancies, serum STN antigen was significantly increased in the following order: Clinical stage I (18%) stage II (22%) stage III (68%). 3) The highest STN value was observed in the cyst fluid from ovarian malignancies. 4) The serum STN concentration was correlated with the effect of treatment. Interestingly, the increase in serum STN preceded the clinical detection of recurrence in one case. Thus STN appears to be a useful marker for monitoring ovarian malignancies.