Table 5. Baseline characteristics of included and excluded patients.
| Variable | Included (n = 85) | Excluded (n = 193) | P value |
|---|---|---|---|
| Sex (male/female) | 78/7 | 187/6 | 0.07 |
| Age (years) | 50 (25−76) | 50 (25−83) | 0.24 |
| Alcohol drinking (ever/never ) | 64/21 | 144/49 | 1.00 |
| Betel quid chewing (ever/never) | 62/23 | 157/36 | 0.15 |
| Cigarette smoking (ever/never) | 70/15 | 168/25 | 0.35 |
| Differentiation (poor/well + moderate) | 13/72 | 16/177 | 0.09 |
| Pathological tumor status (T3 + T4 / T1 + T2) | 44/41 | 101/92 | 1.00 |
| Pathological nodal status (N1 + N2/ N0) | 46/39 | 94/99 | 0.44 |
| Pathological stage (III + IV/I + II) | 58/27 | 134/59 | 0.89 |
| Pathological tumor depth (≥ 10 mm/< 10 mm) | 60/25 | 99/94 | 0.004 |
| Pathological close margin (> 4 mm/≤ 4 mm) | 54/31 | 163/30 | < 0.001 |
| Bone invasion (yes/no) | 20/65 | 50/143 | 0.77 |
| Skin invasion (yes/no) | 13/72 | 19/174 | 0.22 |
| Perineural invasion (yes/no) | 37/48 | 80/113 | 0.79 |
| Lymph invasion (yes/no) | 5/80 | 13/180 | 1.00 |
| Vessel invasion (yes/no) | 1/84 | 3/190 | 1.00 |
| Extracapsular spread (yes/no) | 29/56 | 61/132 | 0.68 |
| Level IV/V metastases (yes/no) | 4/81 | 7/186 | 0.74 |
Data are expressed as counts or medians (ranges), as appropriate. Significant P values are marked in bold.