Table 2.

Advantages and disadvantages of screening and targeted methods for EGFR mutation testing

	Screening methods (samples screened for all EGFR mutations, known and novel variants)	Targeted methods (samples analysed for known EGFR mutations only)
Advantages	▸ All mutations, including novel mutations, may be detected (analytical sensitivity)▸ Direct sequencing technology is widely available	▸ Less time-consuming than the screening method direct sequencing, leading to reduced turnaround times▸ Sensitivity (limit of detection) tends to be higher than with screening methods▸ Technology is fairly widely available
Disadvantages	▸ Sensitivity tends to be lower than with targeted methods▸ Often require enrichment of tumour cells by macro- or micro-dissection▸ Experienced operators needed▸ Tend to be more labour intensive and time consuming than targeted methods, leading to longer turnaround times	▸ Rare mutations not assayed for are not detected▸ Reagents may be more expensive than for screening methods such as direct sequencing

EGFR, epidermal growth factor receptor.