CA 125 levels in endometriosis patients before, during and after treatment with danazol or LHRH agonists

The levels of CA 125 in the serum of 54 patients with endometriosis were measured before, during and after treatment with Danazol or LHRH analogues. Patients with minimal and mild endometriosis had mean pre-treatment values significantly higher than control subjects in the luteal phase of the cycle or postmenopausal women (p less than 0.05), but levels were within the overall control range. In contrast, 78.6% of patients with moderate or severe endometriosis had levels in excess of 30 mu/ml and the mean values for these groups were significantly elevated (p less than 0.005). Levels of CA 125 fell, to those found in normal controls, during treatment, but rose again following cessation of treatment. Six of 12 subjects whose follow-up values of CA 125 exceeded 30 U/ml had a proven recurrence of endometriosis, whilst only 2 of 31 patients with values less than 30 U/ml had laparoscopically proven recurrence.