[Clinical evaluation of specificity of serum CA125 as a tumor marker of ovarian carcinoma]

To evaluate whether elevated serum CA125 levels have specificity to ovarian malignancies, CA125 levels were measured in sera of 48 malignancies, 56 benign diseases and 40 healthy women. Furthermore serum CA125 levels were serially followed up in all the patients with positive serum CA125 levels (35 U/ml less than or equal to) to evaluate the correlation between serum CA125 levels and the response to treatment. Results obtained were as follows. A significantly higher positive rate (91%) of serum CA125 levels was observed in patients with ovarian malignancies than that (30%) in patients with other malignancies. Positive serum CA125 levels were also observed in patients with endometriosis, benign ovarian tumor, hydrosalpinx, uterine myoma and peritoneal tuberculosis. Serum CA125 levels in patients with malignancies depend on the volume of the solid part of the tumor irrespective of the tumor type. In patients with positive serum CA125 levels, rising or falling of the serum levels of this antigen correlated well with progression or regression of all kinds of diseases. These results suggested that a high positive rate of this antigen in patients with ovarian malignancies was not merely derived from the tumor specificity of this marker but partly from the fact that tumor sizes of ovarian malignancies were generally larger than those of other malignancies.