Table 1:
Patients’ characteristics according to the kind of surgery before and after propensity score matching
| Before matching |
After matching |
|||||||
|---|---|---|---|---|---|---|---|---|
| Thymomectomy (n = 129) | Thymectomy (n = 126) | P-Value | Standardized difference | Thymomectomy (n = 88) | Thymectomy (n = 88) | P-Value | Standardized difference | |
| Age >56 years, n (%) | 78 (60.5) | 59 (46.8) | 0.029 | 0.28 | 59 (67.0) | 35 (39.7) | <0.001 | 0.57 |
| Gender male, n (%) | 67 (51.9) | 76 (60.3) | 0.18 | 0.17 | 44 (50.0) | 52 (59.1) | 0.23 | 0.18 |
| Charlson index, n(%) | 0.49 | 0.09 | 1.00 | 0.00 | ||||
| 0–2 | 67 (51.9) | 60 (47.6) | 45 (51.1) | 45 (51.1) | ||||
| 3–7 | 62 (48.1) | 66 (52.4) | 43 (48.9) | 43 (48.9) | ||||
| Stage Masaoka, n (%) | 0.11 | 0.20 | 0.54 | 0.09 | ||||
| I | 65 (50.4) | 51 (40.5) | 41 (46.6) | 37 (42.0) | ||||
| II–III | 64 (49.6) | 75 (59.5) | 47 (53.4) | 51 (58.0) | ||||
| Tumour size >63 mm, n (%) | 67 (51.9) | 61 (48.4) | 0.57 | 0.07 | 54 (61.4) | 54 (61.4) | 1.00 | 0.00 |
| Histology WHO, n(%) | 0.91 | 0.01 | 1.00 | 0.00 | ||||
| A–AB–B1 | 100 (77.5) | 97 (77.0) | 65 (73.9) | 65 (73.9) | ||||
| B2–B3 | 29 (22.5) | 29 (23.0) | 23 (26.1) | 23 (26.1) | ||||
| Approach, n (%) | <0.001 | 0.49 | 1.00 | 0.00 | ||||
| Minimal | 46 (35.7) | 19 (15.1) | 17 (19.3) | 17 (19.3) | ||||
| Open | 83 (64.3) | 107 (84.9) | 71 (80.7) | 71 (80.7) | ||||
| Residual, n (%) | 8 (6.2) | 15 (11.9) | 0.11 | 0.20 | 3 (3.4) | 10 (11.4) | 0.044 | 0.31 |
| Chemotherapy, n (%) | <0.001 | 0.91 | <0.001 | 0.92 | ||||
| Adjuvant | 9 (7.0) | 54 (42.9) | 2 (2.3) | 31 (35.2) | ||||
| None | 120 (93.0) | 72 (57.1) | 86 (97.7) | 57 (64.8) | ||||
| Radiotherapy, n (%) | 0.79 | 0.03 | 0.14 | 0.23 | ||||
| Adjuvant | 14 (10.9) | 15 (11.9) | 6 (6.8) | 12 (13.6) | ||||
| None | 115 (89.1) | 111 (88.1) | 82 (93.2) | 76 (86.4) | ||||
| Death related to thymoma, n (%) | 10 (7.7) | 17 (13.5) | 0.14 | 0.19 | 3 (3.4) | 8 (9.1) | 0.12 | 0.24 |
| Deaths, n (%) | 27 (20.9) | 18 (14.3) | 0.16 | 0.17 | 22 (25.0) | 13 (14.8) | 0.089 | 0.26 |
| Follow-up, months, mean ± SD | 64.1 ± 51.5 | 153.6 ± 107.8 | <0.001 | 1.06 | 59.6 ± 54.8 | 141.7 ± 103.8 | <0.001 | 0.99 |
| Disease-free interval, months, mean ± SD | 60.5 ± 50.4 | 132.6 ± 110.0 | <0.001 | 0.84 | 57.9 ± 54.6 | 122.9 ± 104.8 | <0.001 | 0.78 |
| Time to recurrence, months, mean ± SD | 54.3 ± 42.0 | 32.6 ± 37.9 | 0.14 | 0.54 | 50.7 ± 35.8 | 26.5 ± 35.2 | 0.17 | 0.68 |
| Recurrence, n (%) | 11 (8.5) | 24 (19.0) | 0.015 | 0.31 | 6 (6.8) | 16 (18.2) | 0.023 | 0.35 |
| Recurrence site, n (%) | 0.95 | 0.02 | 0.26 | 0.53 | ||||
| Local | 4 (36.4) | 9 (37.5) | 3 (50.0) | 4 (25.0) | ||||
| Distant | 7 (63.6) | 15 (62.5) | 3 (50.0) | 12 (75.0) | ||||
SD: standard deviation; WHO: World Health Organization.