Epidermal growth factor receptor mutations in non- small cell lung cancers in a multiethnic malaysian patient population.

BACKGROUND: Mutations in the tyrosine kinase domain of the epidermal growth factor receptor (EGFR) in non- small cell lung cancer (NSCLC) are predictive of response to EGFR-targeted therapy in advanced stages of disease. This study aimed to determine the frequency of EGFR mutations in NSCLCs and to correlate their presence with clinical characteristics in multiethnic Malaysian patients. MATERIALS AND METHODS: In this prospective study, EGFR mutations in exons 18, 19, 20 and 21 in formalin-fixed paraffin-embedded biopsy specimens of consecutive NSCLC patients were asessed by real-time polymerase chain reaction. RESULTS: EGFR mutations were detected in NSCLCs from 55 (36.4%) of a total of 151 patients, being significantly more common in females (62.5%) than in males (17.2%) [odds ratio (OR), 8.00; 95% confidence interval (CI), 3.77-16.98; p<0.001] and in never smokers (62.5%) than in ever smokers (12.7%) (OR, 11.50; 95%CI, 5.08-26.03; p<0.001). Mutations were more common in adenocarcinoma (39.4%) compared to non-adenocarcinoma NSCLCs (15.8%) (p=0.072). The mutation rates in patients of different ethnicities were not significantly different (p=0.08). Never smoking status was the only clinical feature that independently predicted the presence of EGFR mutations (adjusted OR, 5.94; 95%CI, 1.94- 18.17; p=0.002). CONCLUSIONS: In Malaysian patients with NSCLC, the EGFR mutation rate was similar to that in other Asian populations. EGFR mutations were significantly more common in female patients and in never smokers. Never smoking status was the only independent predictor for the presence of EGFR mutations.

Outcomes of Malaysian patients with advanced lung adenocarcinoma and unknown epidermal growth factor receptor mutation status treated with gefitinib.

AIMS: To evaluate the response and progression-free survival (PFS) of Malaysian patients with advanced lung adenocarcinoma and unknown epidermal growth factor receptor (EGFR) mutation status treated with gefitinib. METHODS: A retrospective analysis of consecutive patients with EGFR mutation unknown stage III or IV lung adenocarcinoma with EGFR mutation unknown treated with gefitinib until disease progression. RESULTS: Of 71 patients, none had complete response while 26 (36.6%) had partial response and 26 (36.6%) had stable disease. Multivariate analysis showed the independent predictor of response to gefitinib was Eastern Cooperative Oncology Group (ECOG) performance status 1 (odds ratio [OR] 5.39, 95% confidence interval [CI 1.64-17.74]P = 0.006). The median PFS was 6.5 months and was significantly longer in female than male patients (39.0 vs 21.2 weeks; P < 0.001), never smokers vs smokers (32.3 vs 8.3 weeks, P = 0.001), and stage III versus stage IV disease (44 vs 24 weeks, P = 0.021). In a multivariate Cox proportional hazards model with age group, gender, ethnicity, smoking history, disease stage, ECOG performance status and prior cytotoxic chemotherapy as covariates, the independent predictors of longer median PFS were female gender (HR 95% CI 0.38 [0.22-0.66]; P < 0.001) and stage III disease (HR 95% CI 0.54 [0.30-0.98], P = 0.042). CONCLUSION: In our patients with EGFR mutation unknown advanced lung adenocarcinoma treated with gefitinib, the response rate was 36.6% and the median PFS was significantly longer in female patients, never smokers and patients with stage III disease.

Successful pregnancy with epidermal growth factor receptor tyrosine kinase inhibitor treatment of metastatic lung adenocarcinoma presenting with respiratory failure.

We report a woman presenting with respiratory failure due to a right-sided pleural effusion, lung metastases and lymphangitis carcinomatosis from advanced lung adenocarcinoma in the third trimester of pregnancy, who showed good response to EGFR tyrosine kinase inhibitor.