EGFR gene copy number in adenocarcinoma of the lung by FISH analysis: investigation of significantly related factors on CT, FDG-PET, and histopathology.
It has been suggested that a high EGFR gene copy number may be an indicator of good response to EGFR tyrosine kinase inhibitor therapy and a marker of poor prognosis in NSCLC. However, imaging features related to EGFR gene copy number status in adenocarcinoma are still unknown. We therefore retrospectively analyzed CT, FDG-PET, and histopathologic slides of surgical resected lung adenocarcinoma in 132 patients. Tumor characteristics on preoperative chest-CT, such as, GGO proportions, tumor diameters, and cavitation; FDG-PET SUV(max); and histopathologically determined differentiation degrees and tumor subtypes were evaluated. EGFR gene copy number status was categorized as FISH-positive or -negative. FISH-positivity was found in 53 patients (40.2%) and was significantly more frequent in tumors with a SUV(max)>7.0 (P=0.007). Furthermore, FISH-negativity was found to be more frequent in tumors with a GGO>50% (P=0.023) and diameter <15.5mm (P=0.006) on CT, or a well-differentiated histopathology (P=0.002). Moreover, the frequency of FISH-positivity increased as SUV(max) increased (P=0.0008) and as the proportion of GGO decreased (P=0.01). SUV(max)>7.0 was an independent predictor of FISH-positive results (odds ratio, 3.941; 95% CI, 1.691-9.182; P=0.01). In conclusion, a high SUV(max) on FDG-PET was significantly related to FISH-positive results. A high proportion of GGO, small tumor diameter on CT, and a well-differentiated histopathology were more frequent in FISH-negative adenocarcinomas.
Park
Eun-Ah
EA
Department of Radiology, Seoul National University Hospital, 28 Yeongeon-dong, Chongno-gu, Seoul 110-744, Republic of Korea.
Lee
Hyun Ju
HJ
Kim
Young Tae
YT
Kang
Chang Hyun
CH
Kang
Keon Wook
KW
Jeon
Yoon Kyung
YK
Goo
Jin Mo
JM
Lee
Chang Hyun
CH
Park
Chang Min
CM
D000230:Adenocarcinoma / Q000000981:diagnostic imaging* / Q000235:genetics*; D000328:Adult; D000368:Aged; D066246:ErbB Receptors / Q000235:genetics*; D005260:Female; D019788:Fluorodeoxyglucose F18; D018628:Gene Dosage; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D017404:In Situ Hybridization, Fluorescence; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D066246:ErbB Receptors