Predictors of the response to gefitinib in refractory non-small cell lung cancer.
Gefitinib, an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, has a response rate of 10% to 20% in refractory non-small cell lung carcinoma. Although female gender, adenocarcinoma, and never having smoked are possible markers of a favorable response, mutations of the EGFR gene have also been reported to be highly significant predictors of response. Seventy patients with relapsed non-small cell lung carcinoma were enrolled in the Expanded Access Program. After the drug became available commercially, 28 more patients were treated with gefitinib. Response evaluations were feasible in 80 patients. Twenty-seven tumor specimens (8 responders and 19 nonresponders) were available for the sequence analysis of the EGFR gene. The response rate was 25% (20/80) and the disease control rate (remission + stable disease) was 47.5% (38/80). The response rate was significantly higher for adenocarcinoma (41.0%) versus non-adenocarcinoma (9.8%, P = 0.001), in those who never smoked (58.8%) versus smokers (15.9%, P < 0.001), and in females (42.1%) versus males (19.7%, P = 0.049). A deletion or mutation of the EGFR gene was found in six of eight responders. Remission was noted in all patients with a mutation, whereas the response rate was 9.5% (2/21) in patients without a mutation (P < 0.001). The predictors of response showed significant correlations with survival and time to progression. In a multivariate logistic analysis, the independent predictors of response were smoking history and adenocarcinoma. Given that 9.5% of smokers and 6.7% of those with non-adenocarcinoma showed a mutation of the EGFR gene, the genetic profile may replace those variables as an independent predictor of a response.
Kim
Kyu-Sik
KS
Lung and Esophageal Cancer Clinic, Chonnam National University Hwasun Hospital, 160 Ilsim-ri, Hwasun, Jeollanam-do, 519-809 South Korea.
Jeong
Ju-Yeon
JY
Kim
Young-Chul
YC
Na
Kook-Joo
KJ
Kim
Yun-Hyeon
YH
Ahn
Sung-Ja
SJ
Baek
Sun-Mi
SM
Park
Chang-Soo
CS
Park
Chang-Min
CM
Kim
Yu-Il
YI
Lim
Sung-Chul
SC
Park
Kyung-Ok
KO
D000230:Adenocarcinoma / Q000188:drug therapy / Q000235:genetics; D002282:Adenocarcinoma, Bronchiolo-Alveolar / Q000188:drug therapy / Q000235:genetics; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy / Q000235:genetics; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000235:genetics; D018450:Disease Progression; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000235:genetics*; D005240:Feasibility Studies; D005260:Female; D000077156:Gefitinib; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D011237:Predictive Value of Tests; D011379:Prognosis; D011799:Quinazolines / Q000627:therapeutic use*; D012074:Remission Induction; D016879:Salvage Therapy; D015996:Survival Rate; D016896:Treatment Outcome
D000970:Antineoplastic Agents; D011799:Quinazolines; D066246:ErbB Receptors; D000077156:Gefitinib