• cytokeratin 19 fragments;
  • CYFRA 21-1;
  • carcinoembryonic antigen;
  • cytological fluid;
  • computed tomography–guided needle aspiration biopsy;
  • ground-glass opacity



The purpose of this study was to assess whether analyses of tumor markers in cytological fluid can improve the performance of computed tomography (CT)-guided needle aspiration biopsy (NAB) for the diagnosis of ground-glass opacity (GGO) pulmonary lesions.


Forty-two patients were prospectively enrolled for CT-guided NAB. Levels of cytokeratin 19 fragments (CYFRA 21-1) and carcinoembryonic antigen (CEA) from serum and cytological fluid were measured. The cutoff values of 3.3 ng/mL for CYFRA 21-1 and 5.0 ng/mL for CEA (threshold A) or thresholds by adding 2 standard deviations to the mean levels of markers found in patients without malignancy (threshold B) were used to identify malignancy. The sensitivity and area under the curve (AUC) of NAB alone were compared with those of NAB combined with serum or cytological tumor markers.


Among the 42 patients, 30 (71.4%) had malignant and 12 (28.6%) had benign lesions. For NAB alone, the sensitivity, specificity, and AUC for diagnosing GGO were 70.0%, 100%, and 0.850, respectively. The sensitivity and AUC increased significantly for NAB with cytological CYFRA 21-1 compared with NAB alone, using both thresholds (threshold A: 86.7%, P = .026 and .933, P = .016; threshold B: 93.3%, P = .008 and .925, P = .046).


Cytological fluid measurements of CYFRA 21-1 can improve the diagnostic performance of CT-guided NAB for GGO pulmonary lesions. Cancer (Cancer Cytopathol) 2013;121:214–222. © 2012 American Cancer Society.