Radiotherapy in lung adenocarcinoma with brain metastases: Effects of activating epidermal growth factor receptor mutations on clinical response
Journal
Clinical Cancer Research
Journal Volume
14
Journal Issue
1
Pages
162-168
Date Issued
2008
Author(s)
Gow C.-H.
Chien C.-R.
Chiu Y.-H.
Abstract
Purpose: Whole-brain radiation therapy (WBRT) has been applied to inoperable brain metastases in lung adenocarcinoma. Recently, an in vitro studys howed reduced clonogenic survival of mutant epidermal growth factor receptor (EGFR) lung cancer cell lines in response to ionizing radiation compared with that of the wild type. To elucidate the role of EGFR mutations in radiation treatment, we evaluated the clinical response to WBRT and survival of lung adenocarcinoma patients with brain metastases. Experimental Design: This was a retrospective analysis of 63 patients with brain metastases from lung adenocarcinoma who were treated with WBRT. Demographic data, EGFR mutation status, response to WBRT, and survival data were collected. Clinical response was assessed 1 month after the start of WBRT. Univariate and logistic regression models were used to test potential predictive factors associated with clinical response. Log-rank test and Cox regression were analyzed to identify factors that affected survival. Results: Clinical response to WBRT was observed in 29 patients (46%), with 34 nonresponder patients (54%). Patients with EGFR mutations had higher response rates to WBRT compared with those with the wild-type (54% versus 24%; P = 0.045). Both the administration of EGFR tyrosine kinase inhibitor (P = 0.034) and EGFR mutation (P = 0.029) were independently as sociated with response to WBRT. In Cox regression analysis, WBRT responder (P = 0.010) and absence of extracranial metastases (P = 0.002) were associated with better survival. Conclusions: Both the EGFR mutations and the administration of EGFR TKI during WBRT were independent predictors of response to WBRT in brain metastases of lung adenocarcinoma. ? 2008 American Association for Cancer Research.
SDGs
Other Subjects
epidermal growth factor receptor; epidermal growth factor receptor kinase inhibitor; gefitinib; adult; aged; article; brain metastasis; brain radiation; cancer survival; clinical assessment; controlled study; disease association; female; gene mutation; human; human cell; human tissue; log rank test; lung adenocarcinoma; major clinical study; male; priority journal; proportional hazards model; radiation response; treatment response; Adenocarcinoma; Adult; Age Factors; Aged; Aged, 80 and over; Brain Neoplasms; Combined Modality Therapy; Enzyme Inhibitors; Female; Humans; Lung Neoplasms; Male; Middle Aged; Mutation; Protein-Tyrosine Kinases; Radiation Tolerance; Receptor, Epidermal Growth Factor; Retrospective Studies; Smoking
Type
journal article