Analysis of Epidermal Growth Factor Receptor Mutations in Serum Among Japanese Patients Treated With First-Line Erlotinib for Advanced Non-Small-Cell Lung Cancer.
BACKGROUND
Obtaining tumor samples for epidermal growth factor receptor (EGFR) mutation analysis during treatment can be difficult; therefore, serum samples may be a convenient alternative. We analyzed serum EGFR mutations in the Japanese phase 2 JO22903 study in chemotherapy-naive non-small-cell lung cancer patients with tumor EGFR mutations.


METHODS
Serum samples were analyzed by Scorpion-ARMS to detect EGFR mutations before and after erlotinib administration. Agreement between serum and tumor EGFR mutations and time course changes of EGFR mutations were evaluated.


RESULTS
A total of 95 of 103 patients consented to examination of serum samples; baseline serum EGFR mutations (exon 19 deletions or L858R) were detected in 25 patients (26.3%). The agreement rate between tumor and serum samples was 96.2%. Among 65 serum samples taken at 190 days after treatment initiation, EGFR mutations were detected in 5 patients (7.7%). Of the serum samples taken at progression (n = 71), EGFR mutations were detected in 16 patients (22.5%). Patients with baseline serum EGFR mutations had a median progression-free survival of 9.7 months; those without baseline serum mutations had a median progression-free survival of 15.2 months.


CONCLUSIONS
The sensitivity of these analyses was not enough to draw firm conclusions; however, the results suggest that serum EGFR mutations correlate with disease activity.
The Cancer Institute Hospital of JFCR, Tokyo, Japan. Electronic address: mnishio@jfcr.or.jp.
Makoto
M
Nishio
National Cancer Center Hospital East, Chiba, Japan.
Koichi
K
Goto
National Hospital Organization Yamaguchi-Ube Medical Center, Yamauguchi, Japan.
Kenichi
K
Chikamori
Aichi Cancer Center, Nagoya, Japan.
Toyoaki
T
Hida
Institute of Biomedical Research and Innovation, Hyogo, Japan.
Nobuyuki
N
Katakami
Miyagi Cancer Center, Miyagi, Japan.
Makoto
M
Maemondo
Chugai Pharmaceutical Co Ltd, Tokyo, Japan.
Norihisa
N
Ohishi
National Cancer Center Hospital, Tokyo, Japan.
Tomohide
T
Tamura
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood* / Q000235:genetics; D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology; D018450:Disease Progression; D066246:ErbB Receptors / Q000097:blood / Q000235:genetics*; D000069347:Erlotinib Hydrochloride / Q000627:therapeutic use*; D005260:Female; D005500:Follow-Up Studies; D005838:Genotype; D006801:Humans; D008175:Lung Neoplasms / Q000097:blood / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D009367:Neoplasm Staging; D016133:Polymerase Chain Reaction; D011379:Prognosis; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use; D015996:Survival Rate
D014408:Biomarkers, Tumor; D047428:Protein Kinase Inhibitors; D000069347:Erlotinib Hydrochloride; C512478:EGFR protein, human; D066246:ErbB Receptors
Asian; Blood-based; EGFR TKIs; Lung neoplasms; Oncogenic drivers