Table 1.
Patient characteristics
| Characteristic | TSR < − 6.6% | TSR ≥ − 6.6% | P value |
|---|---|---|---|
| No. (%) | No. (%) | ||
| (n = 119) | (n = 116) | ||
| Age, years | 64 (27–82) | 63 (31–85) | 0.149 |
| ≥ 70 | 27 (23%) | 36 (31%) | |
| < 70 | 92 (77%) | 80 (69%) | |
| Sex | 0.318 | ||
| Male | 104 (87%) | 96 (83%) | |
| Female | 15 (13%) | 20 (17%) | |
| ECOG score | 0.228 | ||
| 0–1 | 111 (93%) | 103 (89%) | |
| ≥ 2 | 8 (7%) | 13 (11%) | |
| Smoking status | 0.910 | ||
| ≥ 20 pack/year | 89 (75%) | 84 (72%) | |
| < 20 pack/year | 27 (23%) | 31 (27%) | |
| Missing | 3 (2%) | 1 (1%) | |
| CNS metastasis at baseline | 12 (10%) | 8 (7%) | 0.381 |
| Body mass index (BMI) | 0.891 | ||
| ≥ 24 | 37 (31%) | 37 (32%) | |
| 18.5–23.9 | 69 (58%) | 65 (56%) | |
| < 18.5 | 9 (8%) | 9 (8%) | |
| Missing | 4 (3%) | 5 (4%) | |
| Stage at initial diagnosis | 0.858 | ||
| ED | 65 (55%) | 63 (54%) | |
| LD | 54 (45%) | 54 (46%) | |
| Response to initial chemotherapy | < 0.001* | ||
| CR | 8 (7%) | 0 (0) | |
| PR | 106 (89%) | 68 (59) | |
| SD | 4 (3%) | 25 (21) | |
| PD | 1 (1%) | 23 (20) | |
| Regimen of initial chemotherapy | 0.193 | ||
| Cisplatin plus etoposide | 95 (80%) | 86 (74%) | |
| Carboplatin plus etoposide | 16 (13%) | 17 (15%) | |
| Cisplatin plus irinotecan | 3 (3%) | 4 (3%) | |
| Other* | 5 (4%) | 9 (8%) | |
| Patients with prior radiotherapy | 62 (52%) | 42 (36%) | 0.014* |
BMI: body mass index; CNS: central nervous system; CR: complete response; ECOG: Eastern Cooperative Oncology Group; ED: extensive disease; LD: limited disease; PD: progressive disease; PR: partial response; TSR: tumor shrinkage rate; SD: stable disease