166P - Accuracy of pleural carcinoembryonic antigen (CEA) assay in patients with benign and malignant pleural effusions requiring thoracentesis

Date 17 April 2015
Event ELCC 2015
Session Poster lunch
Topics Supportive Care
Lung and other Thoracic Tumours
Translational Research
Presenter Franco Lumachi
Citation Annals of Oncology (2015) 26 (suppl_1): 51-54. 10.1093/annonc/mdv053
Authors F. Lumachi1, F. Mazza2, A. Del Conte3, G.B. Chiara4, S.M.M. Basso4
  • 1Department Of Surgery Oncology & Gastroenterology (discog), University of Padua, School of Medicine, 35128 - Padova/IT
  • 2Pneumology, S. Maria degli Angeli Hospital, 33170 - Pordenone/IT
  • 3Oncology Unit, Azienda Ospedaliera Sta Maria degli Angeli, 33170 - Pordenone/IT
  • 4Surgery 1, S. Maria degli Angeli Hospital, 33170 - Pordenone/IT

Abstract

Aim/Background

Pleural effusion (PE) is a common condition, which recognizes various etiologies. Malignancies are a frequent cause of PE, but the diagnosis is often difficult, because positive cytology shows low sensitivity (50-60%). Several tumor markers have been tested in differentiating malignant from benign PEs, with the aim of avoiding invasive procedures. The aim of our study was to evaluate the usefulness of the pleural carcinoembryonic antigen (CEA) assay (PCEA) of patients with PE requiring thoracentesis.

Methods

We measured PCEA in 106 patients (65 males, 41 females, mean age 68.5 ± 11.5 years) with PE who underwent videoassisted thoracoscopic (VATS) thoracentesis with minimally invasive biopsy, VATS or open pulmonary resection. The samples were assayed without any pretreatment or particular type of preservation with automated method of immuno-chemiluminescence (LOCI, Dimension Vista, Siemens HD, Camberry, UK). The cut-off used was 5 ng/mL.

Results

Final pathologic evaluation showed 31 (29.2%) non-small cell lung carcinomas (NSCLC), 14 (13.2%) mesotheliomas, 26 (24.6%) metastases and 35 (33.0%) benign lesions. In PE suggesting malignancy (N = 71) the sensitivity of cytology was 57.7%. The PCEA was above the cut-off in 30/31 (96.8%) patients with NSCLC (1096.9 ± 398.9 ng /mL), 2/26 (7.7%) of metastases (31.6 ± 106.9 ng/mL), 1/35 (2.9%) of the benign conditions, and in none patients with mesotheliomas (1.1 ± 0.9 ng/mL). In patients with NSCLC, PCEA measurement was very sensitive (96.8%), while in those with benign lesions it was very specific (97.1%), resulting in an overall diagnostic accuracy of 97% (NSCLC vs. benign).

Conclusions

Our results suggest that PCEA assay is effective, especially in differentiating NSCLC from benign lesions, and can be used in all patients with PE, potentially reducing the need for more invasive procedures.

NSCLC (N = 31) Benign (N = 35) NSCLC (N = 31) vs. Benign (N = 35) Malignant (N = 71) vs. Benign (N = 35)
Sensitivity 96.8% - 96.8% 45.1%
Specificity - 97.1% 97.1% 97.1%
Positive predictive value 100% (95%CI 88.6-100) - 96.8% (95%CI 83.3-99.4) 97.0% (95%CI 84.7-99.4)
Accuracy 96.8% 97.1% 97.0% 62.3%
Prevalence - - 47.0% 67.0%
True positive/ False negative ratio - - 30 0.82

Disclosure

All authors have declared no conflicts of interest.