Comparison of epidermal growth factor receptor mutation statuses in tissue and plasma in stage I-IV non-small cell lung cancer patients.
BACKGROUND
Epidermal growth factor receptor (EGFR) mutations play essential roles in the treatment of non-small cell lung cancer (NSCLC) patients using EGFR tyrosine kinase inhibitors. Detection of EGFR mutations in blood cell-free DNA (cfDNA) seems promising. However, the mutation status in the plasma/serum is not always consistent with that in the tissues.


OBJECTIVE
The aims of this study were to compare the mutation statuses in plasma to those in tissues and thus to determine the specific subgroups of NSCLC patients who may be the best candidates for EGFR mutation analyses using blood cfDNA.


METHODS
A total of 111 pairs of tissue and plasma samples were collected. Mutant-enriched PCR and sequencing analyses were performed to detect EGFR exon 19 deletions and exon 21 L858R mutations.


RESULTS
Mutations were discovered in 43.2% (48/111) of the patients. The overall rate of consistency of the EGFR mutation statuses for the 111 paired plasma and tissue samples was 71.2% (79/111). The sensitivity and specificity rates of detecting EGFR mutations in the plasma were 35.6% (16/45) and 95.5% (63/66), respectively. The disease stage and tumor differentiation subgroups showed significantly different detection sensitivities; the sensitivity was 10% in early-stage patients and 56% in advanced-stage patients (p = 0.0014). For patients with poorly differentiated tumors, the sensitivity was 77.8%, which was significantly different from those with highly differentiated (20%; p = 0.0230) and moderately differentiated tumors (19%; p = 0.0042).


CONCLUSIONS
Blood analyses for EGFR mutations may be effectively used in advanced-stage patients or patients with poorly differentiated tumors.
Department of Respiratory Diseases, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Peking University, Beijing, China.
Xiao
X
Zhao
Ru-Bing
RB
Han
Jing
J
Zhao
Jun
J
Wang
Fan
F
Yang
Wei
W
Zhong
Li
L
Zhang
Long-Yun
LY
Li
Meng-Zhao
MZ
Wang
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000473:pathology; D004252:DNA Mutational Analysis / Q000379:methods; D066246:ErbB Receptors / Q000235:genetics* / Q000378:metabolism; D005091:Exons / Q000235:genetics; D005260:Female; D006801:Humans; D008168:Lung / Q000378:metabolism / Q000473:pathology; D008175:Lung Neoplasms / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009154:Mutation; D016133:Polymerase Chain Reaction; D012680:Sensitivity and Specificity
D066246:ErbB Receptors