Table 2. Clinical Subsets of EGFR-Mutated Patients by Survival Group.
| Characteristic | Category | No. (%) | ||||
|---|---|---|---|---|---|---|
|
|
||||||
| <2 years n = 46 | 2 - <5 years n = 71 | 5+ years n = 20 | Total n = 137 | P Value | ||
| Gender | Female | 35 (76) | 54 (76) | 17 (85) | 106 (77) | 0.75 |
| Male | 11 (24) | 17 (24) | 3 (15) | 31 (23) | ||
|
| ||||||
| Race | White | 41 (89) | 62 (87) | 15 (75) | 118 (86) | 0.14 |
| Asian | 3 (7) | 6 (8) | 4 (20) | 13 (9) | ||
| Black | 0 (0) | 3 (4) | 1 (5) | 4 (3) | ||
| Other/Missing | 2 (4) | 0 (0) | 0 (0) | 2 (1) | ||
|
| ||||||
| Smoking Statusa | Never | 25 (54) | 41 (58) | 11 (55) | 77 (56) | 0.38 |
| Former | 17 (37) | 29 (41) | 9 (45) | 55 (40) | ||
| Current | 4 (9) | 1 (1) | 0 (0) | 5 (4) | ||
|
| ||||||
| Stageb | I | 2 (4) | 5 (7) | 4 (20) | 11 (8) | 0.26 |
| II | 2 (4) | 5 (7) | 1 (5) | 8 (6) | ||
| III | 7 (15) | 4 (6) | 1 (5) | 12 (9) | ||
| IV | 35 (76) | 57 (80) | 14 (70) | 106 (77) | ||
|
| ||||||
| Age at Diagnosis of Metastatic Disease | Mean (SD) | 60.8 (11.8) | 58.5 (10.4) | 59.2 (11.1) | 59.4 (10.9) | 0.48 |
| Median (Q1, Q3) | 63 (53, 70) | 58 (50, 66) | 62 (54, 64) | 60 (51, 67) | ||
|
| ||||||
| Presence of Extrathoracic Metastasisc | No | 13 (28) | 31 (44) | 14 (70) | 58 (42) | 0.01 |
| Yes | 33 (72) | 40 (56) | 6 (30) | 79 (58) | ||
|
| ||||||
| Liver Metastasisc | No | 36 (78) | 61 (86) | 19 (95) | 116 (85) | 0.22 |
| Yes | 10 (22) | 10 (14) | 1 (5) | 21 (15) | ||
|
| ||||||
| Adrenal Metastasisc | No | 44 (96) | 69 (97) | 20 (100) | 133 (97) | 0.81 |
| Yes | 2 (4) | 2 (3) | 0 (0) | 4 (3) | ||
|
| ||||||
| Bone Metastasisc | No | 19 (41) | 44 (62) | 15 (75) | 78 (57) | 0.02 |
| Yes | 27 (59) | 27 (38) | 5 (25) | 59 (43) | ||
|
| ||||||
| Brain Metastasisc | No | 30 (65) | 57 (80) | 20 (100) | 107 (78) | 0.003 |
| Yes | 16 (35) | 14 (20) | 0 (0) | 30 (22) | ||
|
| ||||||
| Exon of EGFR Mutation | 18 | 2 (4) | 2 (3) | 0 (0) | 4 (3) | 0.06 |
| 19 | 19 (41) | 41 (59) | 16 (80) | 76 (55) | ||
| 21 | 24 (52) | 26 (38) | 4 (20) | 54 (39) | ||
| 18, 21d | 0 (0) | 2 (3) | 0 (0) | 2 (1) | ||
| 20, 21d | 1 (2) | 0 (0) | 0 (0) | 1 (1) | ||
|
| ||||||
| EGFR AA Change | Exon 19 Deletion | 19 (41) | 41 (58) | 16 (80) | 76 (55) | 0.09 |
| L858R | 19 (41) | 24 (34) | 4 (20) | 47 (34) | ||
| L861Q/R | 5 (11) | 2 (3) | 0 (0) | 7 (5) | ||
| G719 | 2 (4) | 2 (3) | 0 (0) | 4 (3) | ||
| L861+G719d | 0 (0) | 2 (3) | 0 (0) | 2 (1) | ||
| L858R+T790Md | 1 (2) | 0 (0) | 0 (0) | 1 (1) | ||
|
| ||||||
| EGFR-TKI | Erlotinib | 43 (93) | 61 (86) | 17 (85) | 121 (88) | 0.38 |
| Gefitinib | 3 (7) | 10 (14) | 3 (15) | 16 (12) | ||
|
| ||||||
| Line of TKI | First-Line | 31 (67) | 46 (65) | 16 (80) | 93 (68) | 0.74 |
| Second-Line | 14 (30) | 21 (30) | 3 (15) | 38 (28) | ||
| Third-Line | 1 (2) | 3 (4) | 1 (5) | 5 (4) | ||
| Fourth-Line | 0 (0) | 1 (1) | 0 (0) | 1 (1) | ||
Abbreviations: OS, overall survival; SD, standard deviation; Q1, first quartile; Q3, third quartile; AA, amino acid.
a
Never: <100 lifetime cigarettes; Former: quit ≥1 year before therapy; Current: active or quit within 1 year prior to therapy.
b
Initial staging at time of diagnosis:AJCC Staging System, 7th edition.
c
Presence or absence of metastasis at the specified site, characterized at up to 1 month within start of therapy.
d
Outlier, removed from analysis for the computation of P value.