Background: This study aimed to assess the prognostic accuracy of serum CA 19-9 in patients with advanced lung adenocarcinoma.
Methods: We retrospectively reviewed data of 246 patients who were diagnosed at our institute with advanced (stage IIIB or IV) lung adenocarcinoma between March 2006 and December 2012. We excluded patients who received no chemotherapy, or for whom we had no data on pre-treatment tumor markers. We also evaluated 116 consecutive resected specimens from patients with clinical stage I lung adenocarcinoma pathologically.
Results: The 76 (31 %) patients who were CA 19-9+ had shorter overall survival (OS) than CA 19-9- group (12.5 vs 26.2 months, P = 0.005). Cox's multivariate regression analysis identified Eastern Cooperative Oncology Group Performance Status 0 or 1 (P < 0.001), mutated epidermal growth factor receptor (EGFR) status (P < 0.001), stage IIIB (P < 0.001), CYFRA 21-1- (P < 0.001), CA 19-9- (P = 0.005) and use of platinum doublet therapy (P = 0.034) as independent predictors of longer OS. We stratified patients by CA 19-9 and CYFRA 21-1 as double positive (CA 19-9+/CYFRA 21-1+, n = 59), single positive (either CA19-9+ or CYFRA 21-1+, n = 113), or double negative (CA 19-9-/CYFRA 21-1-, n = 74). Their respective OS were 10.0, 23.3 and 31.8 months (P < 0.001). Pathological analysis also correlated CA 19-9 expression with malignant features such as vessel invasion, pleural invasion, cancer invasive factors and mucin production.
Conclusions: CA 19-9 and CYFRA 21-1 are independent prognostic markers in patients with advanced lung adenocarcinoma. Combined use of CA 19-9 and CYFRA 21-1 provides further prognostic information in patients with advanced lung adenocarcinoma.
Keywords: CA 19-9; CYFRA 21-1; Lung adenocarcinoma; Prognostic marker; Tumor marker.