The genotype and clinical outcomes of patients with rarer mutation or multiple mutations are listed in Table 3. Some of these include mutations known to be associated with sensitivity (L861Q) or resistance (exon 20 insertions) to EGFR-TKI. Other mutations or combinations of mutations, however, occur much less frequently. Of particular note is a patient with both an EGFR exon 19 deletion and a KRAS mutation; this patient did well with erlotinib therapy, achieving stable disease for 25.8 months.