Ovarian cancer: the prognostic value of the serum half-life of CA125 during induction chemotherapy.

Eighty-five patients with epithelial ovarian cancer were studied to assess the prognostic value of the prechemotherapy serum concentration of CA125 and its half-life during induction therapy. The endpoints of the analysis were progression rate and time to progression. The prechemotherapy CA125 level had no prognostic value (P = 0.36) if the patients were stratified for tumor size. The half-life of CA125, however, was an independent prognostic variable (P = 0.01). Patients with a half-life of 20 days and more had a 3.2 times higher progression rate and a significantly shorter median time to progression of only 11 months, as compared to 43 months for patients with a half-life of less than 20 days.