Table 1. Clinical and pathologic characteristics of patients with EGFR mutant NSCLC before and after EGFR-TKI therapy.
| Characteristics | N = 69 |
|---|---|
| Age (mean, Years) | 60.2 (34–78.4) |
| Sex | |
| Men | 19 (27.5%) |
| Women | 50 (72.5%) |
| ECOG Performance status | |
| 0 | 47 (68.1%) |
| 1 | 18 (26.1%) |
| 2 | 4 (5.8%) |
| Smoking history | |
| Current or ex-smoker | 15 (21.7%) |
| Never smoker | 54 (78.3%) |
| Clinical stage at diagnosis | |
| Stage IIIB | 5 (7.2%) |
| Stage IVa | 19 (27.5%) |
| Stage IVb | 45 (65.2%) |
| Presence of brain metastasis | 24 (34.7%) |
| Histology | |
| Adenocarcinoma | 66 (95.7%) |
| Adenosquamous cell carcinoma | 2 (2.9%) |
| Squamous cell carcinoma | 1 (1.4%) |
| EGFR mutation at diagnosis | |
| Exon 19 del | 49 (71.1%) |
| Exon 21 L858R/L861Q | 18 (26.1%) |
| Exon 18 G719X | 1 (1.4%) |
| Exon 20 S768I | 1 (1.4%) |
| Rebiopsy histology | |
| Adenocarcinoma | 59 (85.6%) |
| Small cell carcinoma/neuroendocrine carcinoma | 4 (5.8%) |
| Adenosquamous/Squamous cell carcinoma | 4 (5.8%) |
| Large cell carcinoma | 1 (1.4% |
| Sarcomatoid carcinoma | 1 (1.4%) |
| Acquired EGFR Exon 20 T790M mutation in rebiopsy | |
| Exon20 T790M | 22 (31.9%) |
| No exon20 T790M | 40 (58.0%) |
| Unknown | 7 (10.1%) |
| Treatment just before rebiopsy | |
| EGFR-TKIs | 57 (82.6%) |
| Cytotoxic chemotherapy | 12 (17.4%) |
| Median PFS for EGFR-TKIs | Median Months (95% CI) |
| First line (n = 53) | 13.4 (11.7–15.0) |
| Second line (n = 16) | 20.4 (8.7–32.5) |