"We decided to do the study when we realized that Taiwanese patients were doing much better on Gefitinib than studies from abroad would predict," said Huang Hsiu-feng (黃秀芬), the principle investigator of the research into 65 non-small cell lung cancer patients conducted by the National Health Research Institutes.
According to Huang, they found that more than 50 percent of participants responded to the therapy, in contrast to a response rate of around 10 percent found in Western studies.
"A genetic mutation of the epidermal growth factor receptor [EGFR] is found in most of the patients where Gefitinib helped," Huang explained. "This mutation is rare in the West, but much more common in East Asian countries, contributing to our higher rates of lung cancer."
Carrying this mutation increases one's likelihood of developing adenocarcinoma of the lungs, as opposed to small-cell carcinoma, which is most commonly caused by smoking, he said.
"If a non-smoker develops lung cancer, it is most likely adenocarcinoma," Huang said. "Unfortunately, those cancers are often only discovered in their latter stages, when survival is measured in mere months."
For doctors prescribing the drug, Huang said "it's a numbers game."
Of the roughly 6,800 non-small-cells lung cancer patients in Taiwan every year, 65 percent are adenocarcinoma sufferers, according to a National Health Research Institute news release.
"Of that group, 57 percent will have the gene," Huang said. "And of that 57 percent, roughly half will respond."
For some, like former minister of justice Chen Ding-nan (陳定南), who passed away last week from adenocarcinoma, Gefitinib has little effect.
"He wasn't among the percentage who respond," Huang said.
source - The TaiPei Times