Youkyung Lee MD, Presenter: Nothing to Disclose

Hyun Ju Lee MD, Abstract Co-Author: Nothing to Disclose

Young Tae Kim, Abstract Co-Author: Nothing to Disclose

Chang Hyun Kang, Abstract Co-Author: Nothing to Disclose

Jin Mo Goo MD, PhD, Abstract Co-Author: Nothing to Disclose

Chang Min Park, Abstract Co-Author: Nothing to Disclose

So Young Choi MD, Abstract Co-Author: Nothing to Disclose

00030490-DMT et al, Abstract Co-Author: Nothing to Disclose

To identify CT and FDG-PET features of stage I non-small cell lung cancer (NSCLC) that correlate with epidermal growth factor receptor (EGFR) protein overexpression, and to evaluate the value of imaging features and EGFR expression in the prediction of early recurrence after curative resection.  

In 220 patients (M:F=135:85; mean age, 63) who underwent curative resection of stage I NSCLC between Oct. 2005 and Dec. 2007, EGFR protein expression was determined by immunohistochemical analysis. EGFR overexpression was defined as when >10% of tumors were stained with monoclonal anti-EGFR. Imaging characteristics on CT and FDG-PET in terms of SUVmax, GGO proportions, tumor diameters, cavitation, air-bronchogram, marginal spiculation and lobulation were correlated with EGFR expression status using the Chi-square test and multivariate logistic regression analysis. Mean follow-up period was 663 days. The value of imaging features and EGFR expression status for prediction of early recurrence was evaluated using Cox proportional hazards model and the Chi-square test.

EGFR overexpression was found in 55 patients (25%): in 22 of 136 adenoca (16.2%), 26 of 55 squamous cell ca (47.3%), 0 of 11 BACs (0%), and 2 of 9 large cell ca (22.2%). EGFR overexpression was significantly frequent in tumors with SUVmax >6.2 (P<0.0001), diameter >24 mm (P<0.0001), and in GGO ≤50% (P=0.006). The frequency of EGFR overexpression was 28.3% in tumors with ≤ 50% of GGO, but 6.1% in tumors with > 50% GGO. SUVmax >6.2 (odds ratio, 3.8; 95% CI, 1.7–8.1; P=0.01) and diameter >24 mm (odds ratio, 2.8; 95% CI, 1.3–6.1; P=0.08) were independent predictors of EGFR overexpression. Recurrence rate at 1 year was significantly higher in tumors with EGFR overexpression (P=0.04), SUVmax >6.2 (P=0.03), diameter >24 mm (P=0.008), and absence of air-bronchogram (P=0.02). Diameter >24 mm was an independent predictor of shorter time to recurrence (hazard ratio, 5.0; 95% CI, 2.1–11.7; P=0.0001).

EGFR expression status was significantly associated with SUVmax, diameter, and GGO proportion of stage I NSCLC. Imaging characteristics as well as EGFR expression status can be valuable in the prediction of early recurrence.

Examination of the relationship between imaging characteristics and molecular studies can establish an important clinical profile with which we can identify patients at high risk for tumor recurrence.

Lee, Y, Lee, H, Kim, Y, Kang, C, Goo, J, Park, C, Choi, S, et al, 0, Imaging Characteristics of Stage I Non–Small Cell Lung Cancer on CT and FDG-PET: Relationship with EGFR Protein Expression Status and Time to Recurrence.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8011033.html