[Clinical usefulness of a new tumor marker CYFRA21-1 in patients with lung cancer].
OBJECTIVE
To set the serum cut-off value of CYFRA21-1 in lung cancer patients in china, and to evaluate the clinical usefulness of CYFRA21-1 as a new tumor marker of lung cancer.


METHODS
CYFRA21-1 levels were measured with two monoclonal antibodies (Ks19.1 and BM19.21) in the serum of 72 patients with lung cancer, 50 patients with benign lung diseases and 33 post-therapy lung cancer patients. To set the cut-off value, ROC curve was use.


RESULTS
(1) Serum concentrations of CYFRA21-1 in patients with lung cancer were significantly higher than those with benign lung diseases (P < 0.001). CYFRA21-1 levels in patients with squamous cell carcinoma were significantly higher than those in patients with any other subtypes. The more advanced the clinical stages, the higher the levels of CYFRA21-1. (2) If the threshold of CYFRA21-1 was set at 5.5 micrograms/L, its sensitivity and specificity for lung cancer were 63% and 94%, respectively. The sensitivity for squamous cell carcinoma was 78%, which was the highest among all the pathological subtypes. (3) The sensitivity of CYFRA21-1 in non-small cell lung cancer increased with the advancement of clinical stages. (4) CYFRA21-1 could be a good index in monitoring patient's condition and predicting prognosis for lung cancer. (5) When CYFRA21-1 was used as a screening index for lung cancer, the threshold of CYFRA21-1 should be set at the upper left corner of the receiver operating characteristic curve of stage I-II. The value of CYFRA21-1 in early diagnosis for non-small cell lung cancer was found limited.


CONCLUSIONS
CYFRA21-1 is a sensitive and specific tumor marker of non-small cell lung cancer, especially of squamous cell carcinoma.
Li
R
R
Department of Medical Oncology, First Clinical Medical College, Xi'an Medical University, Xi'an 710061.
Li
R
R
Wang
Y
Y
D000230:Adenocarcinoma / Q000097:blood / Q000473:pathology; D000328:Adult; D000368:Aged; D000951:Antigens, Neoplasm / Q000097:blood*; D014408:Biomarkers, Tumor / Q000097:blood*; D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood* / Q000473:pathology; D018288:Carcinoma, Small Cell / Q000097:blood / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000097:blood / Q000473:pathology; D005260:Female; D006801:Humans; D053539:Keratin-19; D007633:Keratins; D008175:Lung Neoplasms / Q000097:blood* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging
D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D053539:Keratin-19; C102012:antigen CYFRA21.1; D007633:Keratins