Lung cancer is the second most commonly diagnosed cancer and the leading cause of cancer death in 2020[1]. Non-small cell lung cancer (NSCLC) accounts for the majority (approximately 85 percent) of lung cancers with the remainder as mostly small cell lung cancer (SCLC). For each patient with suspected lung cancer the overall goal is a timely diagnosis and accurate staging so appropriate therapy can be administered.
Blood-based biomarkers are valuable diagnostic tools for the management of lung cancer patients. They support not only differential diagnosis and histological subtyping, but are also applied for estimation of prognosis, stratification for specific therapies, monitoring of therapy response, surveillance monitoring and early detection of residual or progressive disease. [2]
CEA, CYFRA21-1 and NSE are tumor markers used for monitoring the response to chemotherapy in advanced adenocarcinoma, squamous cell carcinoma and small-cell lung cancer, respectively. ProGRP is a useful marker in SCLC, demonstrating association with survival in NSCLC and SCLC limited to univariate analysis.[3] SCCA has been confirmed to be closely related to the prognosis of lung cancer[4] ,especially squamous cell carcinoma.
Clinical Significance
Elevated expression of tumor CEA may be an adverse prognostic indicator in stages IB NSCLC. According to retrospective studies, high CEA level was a negative prognostic factor for survival and a risk factor for occult regional node metastasis in clinical stage I NSCLC patients undergoing surgery.