The clinical value of Cyfra 21-1 estimation for lung cancer patients

Int J Biol Markers. Jul-Sep 1996;11(3):172-7.


Cytokeratin-19, one of the cytoskeletal proteins, is expressed both in bronchial epithelium and in lung cancer cells. The aim of our study was to establish the value of serum cytokeratin-19 soluble fragment (Cyfra 21-1) measurement in lung cancer patients. Cyfra 21-1 levels were estimated in 35 patients (pts) with benign lung diseases and in 116 lung cancer patients: 55 pts with squamous cell lung cancer, 38 pts with small cell lung cancer and 23 pts with adenocarcinoma. The cutoff level was set at 4 ng/ml with a specificity of 94% and a sensitivity of 40%. Elevated Cyfra 21-1 values were found in 44% of squamous cell lung cancer, 39% of adenocarcinoma and 34% of small cell lung cancer pts (the difference was not significant). In squamous cell lung cancer and in adenocarcinoma elevated Cyfra 21-1 values were observed more often in patients with advanced disease than in patients with limited disease. There was no significant correlation between the initial Cyfra 21-1 level and the response to chemotherapy. Cyfra 21-1 was not a prognostic indicator, although in operable squamous cell lung cancer the proportion of survivors in the second year of observation was higher among the patients with normal preoperative Cyfra 21-1 levels.

MeSH terms

  • Adenocarcinoma / blood
  • Adult
  • Aged
  • Antigens, Neoplasm / blood*
  • Biomarkers, Tumor / blood
  • Carcinoma, Small Cell / blood
  • Carcinoma, Squamous Cell / blood
  • Female
  • Humans
  • Keratin-19
  • Keratins
  • Lung Neoplasms / blood*
  • Male
  • Middle Aged
  • Survival


  • Antigens, Neoplasm
  • Biomarkers, Tumor
  • Keratin-19
  • antigen CYFRA21.1
  • Keratins