Table 1. Demographics and relationship between clinical variables and antitumor response/overall survival in patients treated with gefitinib.
| Characteristic | No. of patients (%) | PR (n) | RR (%) | (95% CI) | P-value* | MST (months) | (95% CI) | P-value |
|---|---|---|---|---|---|---|---|---|
| All | 221 | 54 | 24.4 | (18.9–30.6) | 8 | (6.66–9.34) | ||
| Gender | ||||||||
| Male | 142 (64) | 20 | 14.1 | (8.8–20.9) | <0.001 | 6.8 | (5.04–8.56) | 0.036 |
| Female | 79 (36) | 34 | 43 | (31.9–54.7) | 13.3 | (8.84–17.76) | ||
| Age | ||||||||
| 65< | 100 | 20 | 20 | (12.7–29.2) | 0.208 | 9 | (6.41–11.59) | 0.2852 |
| <65 | 121 | 34 | 28.1 | (20.3–37.0) | 7.3 | (5.88–8.72) | ||
| ECOG PS | ||||||||
| 0–1 | 160 (72) | 44 | 27.5 | (20.7–35.1) | 0.114 | 11.1 | (8.30–13.90) | <0.001 |
| 2–4 | 61 (28) | 10 | 16.4 | (8.2–28.1) | 2.1 | (1.26–2.94) | ||
| Histology | ||||||||
| Adenocarcinoma | 196 (89) | 52 | 26.5 | (20.5–33.3) | 0.048 | 9.3 | (7.66–10.94) | 0.137 |
| Others | 25 (9) | 2 | 8 | (1.0–26.0) | 3.6 | (2.13–5.07) | ||
| Prior chemotherapy | ||||||||
| Yes | 188 (85) | 45 | 24.6 | (18.5–43.3) | 1 | 8.1 | (6.67–9.53) | 1 |
| No | 33 (15) | 9 | 25.7 | (12.5–43.3) | 8.4 | (5.72–11.08) | ||
| Smoking history (n=220) | ||||||||
| No | 89 (40) | 37 | 41.6 | (31.2–52.5) | <0.001 | 14.5 | (10.87–18.13) | <0.001 |
| Yes | 131 (15) | 17 | 13 | (7.7–20.0) | 6.5 | (4.36–8.64) | ||
| BI 1<500 | 25 (11) | 5 | 20 | (6.8–40.7) | 9.5 | (6.41–12.59) | ||
| BI 500 to <1000 | 59 (27) | 9 | 15.3 | (7.2–27.0) | 6.9 | (5.64–8.16) | ||
| BI⩾1000 | 45 (21) | 2 | 4.4 | (0.5–15.1) | 4 | (3.00–5.00) | ||
| EGFR gene status (n=91) | ||||||||
| Wild type | 63 (69) | 7 | 11.1 | (4.6–21.6) | <0.001 | 7.4 | (4.84–9.96) | <0.001 |
| Mutation positive | 28 (31) | 20 | 71.4 | (51.3–86.8) | 24.9 | (14.27–35.53) | ||
| Exon 19 deletion | 19 (21) | 15 | 78.9 | (54.4–93.9) | 16.1 | (6.22–25.98) | ||
| Exon 21 (L858R) | 9 (10) | 5 | 55.6 | (21.2–86.3) | >34.5 | — | ||
| Tumor response (n=191) | ||||||||
| PR | 54 | — | — | 26.2 | (15.76–36.64) | 0.003 | ||
| SD | 59 | — | — | 11.9 | (7.47–16.33) | <0.0001 | ||
| PD | 78 | — | — | 5.6 | (3.20–8.00) | |||
Abbreviations: BI=Brinkman Index; BI=defined as number of cigarettes per day × number of years smoking; CI=confidence interval; EGFR=epidermal growth factor receptor; ECOG PS=Eastern Cooperative Oncology Group performance status; MST=median survival time; PD=progressive disease; PR=partial response; RR=response rate; SD=stable disease.*Fisher's exact test.