Decline of posttreatment tumor marker levels after therapy of nonsmall cell lung cancer. A useful outcome predictor

Abstract

Background. The assessment of treatment efficacy in nonsmall cell lung cancer (NSCLC) is limited by the lack of a clear association between clinical response and survival. The prognostic usefulness of treatment‐induced tumor‐marker declines in NSCLC has not been established. The authors investigated the prognostic significance of treatment‐induced declination in tumor marker levels of carcinoembryonic antigen, CA 19‐9, and CA 125 in a group of patients with NSCLC treated with a brief course of cisplatin‐based chemotherapy. Methods. Eighty‐three patients with NSCLC enrolled on 2 related treatment protocols had pretreatment tumor‐marker determinations. Patients were restaged 10 to 12 weeks after study entry, and clinical and marker responses were determined. Results. Thirty‐eight patients (46%) had elevated pretreatment tumor markers, 36 (42%) of whom were evaluable for both clinical and marker responses. Pretreatment, the latter 36 individuals had measurable or evaluable disease, and at least one elevated tumor marker (greater than twice normal); posttreatment, they had follow‐up measurements of both parameters. Of the 36 patients, 8 had normalization of tumor marker levels, 13 had 50‐99% marker level declination, and 15 had less than 50% or no declination. In the same group of 36 patients, there were, 1 patient with complete clinical response, 11 with partial response, 19 with stable disease, and 5 with progressive disease. Marker responses occurred with equal frequency in clinical responders an nonresponders. There was no association between clinical response and survival, but there was a strong association between marker response and survival. Conclusions. In patients with nonsmall cell lung cancer with elevated pretreatment tumor marker level: treatment‐induced marker level declination can be a surrogate indicator for survival. Cancer 1995;75:1586‐93. Copyright © 1995 American Cancer Society