Table 1. Clinical characteristics of patients.
| No. of patients (%) | Treatment groups | p-value | ||
|---|---|---|---|---|
| Pemetrexed maintenance | Conventional chemotherapy | |||
| All | 114 (100) | 41 (36) | 73 (64) | |
| Sex | 0.273 | |||
| Female | 35 (31) | 10 (25) | 25 (34) | |
| Male | 79 (69) | 31 (75) | 48 (66) | |
| Age, yr | 0.208 | |||
| <65 | 59 (52) | 18 (44) | 41 (56) | |
| ≥65 | 55 (48) | 23 (56) | 32 (44) | |
| Smoking | 0.890 | |||
| Never | 38 (33) | 14 (34) | 24 (33) | |
| Ever | 76 (67) | 27 (66) | 49 (67) | |
| ECOG performance status | 0.541 | |||
| 0, 1 | 95 (83) | 33 (80) | 62 (84) | |
| ≥2 | 19 (17) | 8 (20) | 11 (16) | |
| T stage | 0.614 | |||
| T1 | 7 (6) | 3 (7) | 4 (5) | |
| ≥T2 | 107 (94) | 38 (93) | 69 (95) | |
| N stage | 0.855 | |||
| N0 | 9 (8) | 4 (10) | 5 (7) | |
| ≥N1 | 105 (92) | 37 (90) | 68 (93) | |
| Stage | 0.215 | |||
| IIIB | 10 (9) | 2 (5) | 8 (11) | |
| IV | 104 (91) | 39 (95) | 65 (89) | |
| Metastatic organs | 0.329 | |||
| 0–2 | 72 (63) | 30 (73) | 42 (56) | |
| ≥3 | 42 (37) | 11 (27) | 31 (44) | |
| Brain metastasis | 0.182 | |||
| No | 70 (61) | 29 (70) | 41 (55) | |
| Yes | 44 (39) | 12 (30) | 32 (43) | |
| ALK translocation* | 0.711 | |||
| Negative | 45 (83) | 16 (80) | 29 (85) | |
| Positive | 9 (16) | 4 (20) | 5 (15) | |
| KRAS mutation* | 0.168 | |||
| Negative | 36 (83) | 11 (100) | 25 (66) | |
| Positive | 7 (17) | 0 (0) | 7 (34) | |
| Differentiation | 0.276 | |||
| Well | 78 (69) | 30 (74) | 48 (66) | |
| Moderate-poor | 36 (31) | 11 (26) | 25 (34) | |
| Second-line treatment | 0.805 | |||
| Yes | 82 (72) | 29 (70) | 53 (73) | |
| No | 18 (28) | 12 (30) | 6 (27) | |
| Second-line regimens† | 0.279 | |||
| EGFR-TKIs | 26 (32) | 8 (27) | 18 (34) | |
| Pemetrexed | 14 (17) | - | 14 (26) | |
| Gemcitabine | 15 (18) | 9 (31) | 6 (11) | |
| Vinorelbine | 10 (12) | 6 (21) | 4 (8) | |
| Taxens | 11 (13) | 4 (14) | 7 (12) | |
| Crizotinib | 6 (7) | 2 (7) | 4 (8) | |
Values are presented as number (%).
*ALK translocation and KRAS mutation data were available in 54 and 43 patients, respectively. †82 patients received second-line treatment.
ECOG: Eastern Cooperative Oncology Group; T: tumor; N: lymph node; ALK: anaplastic lymphoma kinase; KRAS: Kirsten rat sarcoma; EGFR-TKI: epidermal growth factor receptor tyrosine kinase inhibitor.