. 2011 Jun;23(2):112–117. doi: 10.1007/s11670-011-0112-5

Table 3. Clinical outcome by subgroups: EGFR mutation status, tumor histology, sex and smoking history.

Subgroup	Progression-free survival (months)^a				Overall survival (months)^a
	Immediate	Delayed	PFS for Immediate Vs. delyayed	P	Immediate	Delayed	OS for Immediate Vs. delyayed	P
	Median	Median	HR(95%CI)^b	P	Median	Median	HR(95%CI)^b	P
EGFR mutation positive^c	27.2	13.5	0.48	0.012	33.2	24.9	0.53	0.072
			(0.27-0.85)				(0.27-1.06)
EGFR mutation negative	13.0	15.6	1.23	0.564	24.3	21.3	1.19	0.660
			(0.61-2.51)				(0.55-2.58)
Adenocarcinoma^d	17.3	12.0	0.73	0.115	26.1	20.2	0.81	0.331
			(0.49-1.08)				(0.52-1.25)
Non-adenocarcinoma	18.3	24.8	1.83	0.530	30.2	24.9	0.48	0.571
			(0.28-12.11)				(0.04-6.25)
Female	15.4	16.6	0.97	0.905	24.0	23.3	1.02	0.955
			(0.57-1.66)				(0.57-1.81)
Male	18.3	14.2	0.87	0.125	25.2	23.8	0.95	0.871
			(0.35-1.26)				(0.56-1.45)
Never smoker^e	17.5	14.7	0.76	0.189	26.3	21.9	0.76	0.231
			(0.50-1.15)				(0.48-1.19)
Ever smoker	12.9	11.6	0.59	0.252	26.1	19.9	0.63	0.406
			(0.24-1.45)				(0.21-1.87)

^a: The statistical analysis was based upon the entire sample of 159 subjects; b: Hazard ratio was calculated against the delayed group using a Cox proportional-hazards model, with sex, smoking history, and histology as covariantes; c: EGFR mutation included exon 19 deletion and exon 21 L858R only; d: Also included bronchoalveolar carcinoma; e: <100 cigarettes in lifetime.