Table 1 Patient characteristics

Age (range)

63 (42–85)

59 (36–80)

0.59

Sex (male/female)

11/14

10/18

0.54

ECOG

  0

1 (4.0)

0 (0.0)

0.01

  1

12 (48.0)

24 (85.7)

  2

12 (48.0)

4 (14.3)

  0/1 vs. 2

13 (52.0) vs. 12 (48.0)

24 (85.7) vs. 4 (14.3)

0.008

Smoking status

0.88

  Never smokers

22 (88.0)

25 (89.3)

  Current or past smokers

3 (12.0)

3 (10.7)

Histology

0.31

  Adenocarcinoma

23 (92.0)

28 (100.0)

  Squamous cell carcinoma

1 (4.0)

0 (0.0)

  Bronchoalveolar carcinoma

1 (4.0)

0 (0.0)

Initial EGFR mutation status at diagnosis

0.79

  exon 18 mutation

0

1

  exon 19 deletion

11

13

  exon 19 substitution mutation

1

1

   L858R

8

10

   L861Q

0

2

  double mutations

1

1

EGFR mutation status with re-biopsy before afatinib or erlotinib

T790M alone

4

unknown

NA

Brain metastasis before afatinib or erlotinib

6 (24.0)

13 (46.4)

0.09

1^st TKI therapy

NA

  Gefitinib

14 (56.0)

28 (100)

  Erlotinib

11 (44.0)

0 (0)

Median duration of therapy (months, range)

14.5 (3.52–40.64)

9.2 (2.63–24.61)

0.02

 Median Time to progression (months range)

13.9 (0.66–40.15)

9.1 (2.52–24.57)

0.14

 Best response

0.42

  CR

1 (4.0)

1 (3.6)

  PR

23 (92.0)

23 (82.1)

  SD

0 (0.0)

3 (10.7)

  PD

1 (4.0)

1 (3.6)

Number of lines of prior chemotherapy before afatinib or erlotinib

0.08

  1

14 (56.0)

22 (78.6)

  2

11 (44.0)

6 (21.4)

First-line chemotherapy before afatinib or erlotinib

25 (100)

28 (100)

0.88

   Pemetrexed + cisplatin

3 (12.0)

6 (21.4)

   Pemetrexed + carboplatin

9 (36.0)

7 (25.0)

   Paclitaxel + carboplatin

4 (16.0)

4 (14.3)

   Gemcitabine + carboplatin

5 (20.0)

5 (17.9)

   Carboplatin

2 (8.0)

2 (7.1)

   Pemetrexed

2 (8.0)

4 (14.3)

 Median duration of therapy (months, range)

3.50 (0.69–17.97)

2.96 (0.66–17.02)

0.85

 Median time to progression (months, range)

3.35 (0.69–17.97)

3.48 (0.85–16.95)

0.76

Second-line chemotherapy before afatinib or erlotinib

11 (44.0)

6 (21.4)

0.08

   Pemetrexed + carboplatin

1 (4.0)

0 (0.0)

   Paclitaxel + carboplatin

2 (8.0)

2 (7.1)

   Gemcitabine + carboplatin

5 (20.0)

4 (14.3)

   Docetaxel

1 (4.0)

0 (0.0)

   Vinorelbine

1 (4.0)

0 (0.0)

   Pemetrexed

1 (4.0)

0 (0.0)

Median duration of therapy (months, range)

2.30 (0.66–9.63)

2.92 (0.69–4.34)

0.91

Median time to progression (months, range)

3.09 (0.66–10.28)

3.25 (0.72–4.44)

0.74

Median time interval between 1^st TKI therapy and afatinib or erlotinib (months, range)

8.38 (2.30–54.28)

6.39 (2.56–20.07)

0.15

Median time interval between last chemotherapy and afatinib or erlotinib (months, range)

2.79 (0.46–34.28)

2.58 (0.23–17.05)

0.49