Purpose: To investigate the clinical value in lung cancer of a combination of four serum tumor markers,haptoglobin (Hp), carcinoembryonic antigen (CEA), neuron specific enolase (NSE) as well as the cytokeratin 19fragment (CYFRA21-1). Materials and
Methods: Serum Hp (with immune-turbidimetric method), CEA, NSE,CYFRA21-1 (with chemiluminescence method) level were assessed in 193 patients with lung cancer, 87 patientswith benign lung disease and 150 healthy controls. Differences of expression were compared among groups,and joint effects of these tumor markers for the diagnosis of lung cancer were analyzed.
Results: Serum tumormarker levels in patients with lung cancer were obviously higher than those with benign lung disease and normalcontrols (p<0.01). The sensitivities of Hp, CEA, NSE and CYFRA21-1 were 43.5%, 40.9%, 23.3% and 41.5%,with specificities of 90.7%, 99.2%, 97.9% and 97.9%. Four tumor markers combined together could produce apositive detection rate of 85.0%, significantly higher than that of any single test. With squamous carcinomas, thepositive detection rates with Hp and CYFRA21-1 were higher than that of other markers. In the adenocarcinomacase , the positive detection rate of CEA was higher than that of other markers. For small cell carcinomas, thepositive detection rate of NSE was highest. The area under receiver operating characteristic curve (AUCROC) ofHp in squamous carcinoma (0.805) was higher than in adenocarcinoma (0.664) and small cell carcinoma (0.665).
Conclusions: Hp can be used as a new serum tumor marker for lung cancer. Combination detection of Hp, CEA,NSE and CYFRA21-1 could significantly improve the sensitivity and specificity in diagnosis of lung cancer, andcould be useful for pathological typing.