Ethnicity affects response to lung cancer treatment
An analysis of studies spanning 35 years shows a better survival rate among Asian patients with non-small cell lung cancer (NSCLC) compared with whites—a difference that should be taken into consideration when clinical trials are being designed, say the researchers.
“It is recognized that Asian patients [with NSCLC] have a better survival than Caucasian patients when treated with chemotherapy,” noted Ross Soo, MB, BS, in a statement describing his team's findings, which were reported in the Journal of Thoracic Oncology (2011;6:1030-1038). What wasn't known previously was whether this effect was seen in patients given just one or a combination of drugs. Furthermore, the improved survival could have been due to the better chance of targeted therapy working in Asians.”
Soo—senior consultant in the Department of Haematolgy-Oncology at the National University Hospital in Singapore—and colleagues performed a meta-analysis of 191 randomized controlled trials published between 1975 and 2010, involving 6,806 Asian and 41,563 white persons with NSCLC. Median overall survival rates for all chemotherapy regimens reviewed were 10.1 months for Asian patients and 8.0 months for whites; median overall response rates were 32.2% among Asians and 25.9% among whites. Median overall survival was:
- 9.9 months for Asians and 6.8 months for whites for monotherapy
- 10.4 months for Asians and 8.6 months for whites for platinum doublets
- 9.4 months for Asians and 8.0 months for whites for combinations of three or more drugs.
The epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) gefitinib and erlotinib were introduced in many Asian countries in 2002 and were associated with an improvement in overall survival for Asian patients: from a median of 9.1 months in the pre-EGFR-TKI years (vs. 7.3 months for whites), to a median of 11.0 months thereafter (vs. 8.9 months for whites).
“Ethnic differences in survival and response rate to chemotherapy exist and should be considered in clinical trial designs, especially in the global context,” concluded the investigators.