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Combines assessment of six Tumor Markers for the Diagnosis and Histological Diagnosis of Lung Cancer

Rafael Molina1,*

1Biochemistry, Hospital Clinic. Medical School, Barcelona, Spain, Spain, Spain

We previously identified six serum tumor markers (TM) (CEA, CA15.3, SCC, CYFRA 21-1, NSE and ProGRP) related to lung cancer (LC).

OBJECTIVES: This study sought to (1) validate prospectively the diagnostic performance of these six TM in an independent and larger cohort; and, (2) test the hypothesis that their combined assessment (i.e., presence of ≥1 abnormal TM value) improves it.

METHODS. We recruited 3,144 consecutive individuals (none of them included in our previous studies), referred to our institution because of the clinical suspicion of LC.

MEASUREMENTS AND MAIN RESULTS. Using standard clinical procedures, LC was excluded in 1,316 individuals (41.8%) and confirmed in 1,828 patients (58.2%), of whom 1,563 (85.5%) had non-small cell LC (NSCLC) and 265 (14.5%) small-cell LC (SCLC). Main results: (1) validated the previously published diagnostic performance of each individual TM; and, (2) showed that, as hypothesized, their combined assessment improved it, with a sensitivity of 88.5%, a specificity of 82%, a negative predictive value of 83.7% and a positive predictive value of 87.3%. In patients with early stages of LC these figures were, respectively, 70,4%, 82%, 90,7% and 52,9% for NSCLC stage I/II, and 94.3%, 82%, 99,4% and 29.6% for intra-thoracic SCLC. Finally, two TM (NSE and ProGRP) significantly differentiate NSCLC from SCLC (AUC 0.894 and 0.861, respectively). Combination of these 6 tumor markers allow to differentiate Adenocarcinoma from Squamous NSCLC with a sensitivity higher than 85% and a specificity higher than 90%.

CONCLUSIONS. The combined assessment (i.e., ≥1 abnormal TM value) of these six TM improve their individual performance for the diagnosis of LC.

Keywords: Biomarker, Cancer