ABSTRACT
<p><b>OBJECTIVE</b>To investigate the value of carcinoembryonic antigen (CEA) or cytokeratin 19 fragment (CYFRA21-1) as an assessment indicator of therapeutic efficacy in advanced non-small cell lung cancer (NSCLC) patients.</p><p><b>METHODS</b>228 cases of advanced NSCLC with chemotherapy were enrolled into this retrospective study. The serum CEA or CYFRA21-1 levels of all patients were above the cut-off limit before treatment. The relationship between changes of tumor markers (TMs) and imaging therapeutic efficacy or progression-free survival (PFS) was analyzed, and the value of TMs in therapeutic efficacy assessment was evaluated.</p><p><b>RESULTS</b>According to RECIST criteria, partial response (PR) occurred in 40 cases, stable disease (SD) in 151 and PD (progressive disease) in 37. The cut-off values of the changes of TMs between pre- and post-treatment were determined according to the above mentioned criteria. The CEA down (D), stable (S), above (A) groups were 90, 49 and 66 cases, respectively. CYFRA21-1 down (D), stable (S), above (A) groups were 84, 26 and 37 cases, respectively. PR groups were 68.4% and 88.9% in CEA and cyfra21-1 down groups, respectively, 7.9% and 5.6% in the above groups, respectively. PD groups were 59.4% and 76.2% in CEA and CYFRA21-1 above groups, respectively. No PD cases were in the down groups. The changes of TMs in SD group were between them. Statistically significant correlations were observed between changes of TMs and imaging therapeutic efficacy (r(CEA) = 0.45, P = 0.00; r(CYFRA21-1) = 0.44, P = 0.00). PFS among different TMs groups were significantly different (all P < 0.05), which can be used to further distinguish the prognosis among SD subgroups.</p><p><b>CONCLUSION</b>Changes of TMs can be used to predict the imaging therapeutic effect and PFS of the patients, and if the SD group is divided into subgroups according to different therapeutic efficacy and prognosis, it may help the patients to receive individualized treatment.</p>