Epidermal growth factor receptor mutation analysis in previously unanalyzed histology samples and cytology samples from the phase III Iressa Pan-ASia Study (IPASS)

Histology samples with low tumor content and cytology samples can be used for EGFR mutation testing; patients whose mutation status was confirmed using these sample types achieved a response to treatment consistent with those confirmed using high-quality histology samples. Better sample quantity/quality can potentially reduce false-negative results.