TABLE 1.
Patient and tumor characteristics and true N‐classification
| True N negative | True N positive | p‐value | |
|---|---|---|---|
| n (%) | n (%) | ||
| Total | 57 (66) | 30 (34) | |
| Sex | |||
| Male | 30 (53) | 12 (40) | 0.367 |
| Female | 27 (47) | 18 (60) | |
| Age at first treatment | |||
| Median (IQR) | 64 (57–71) | 66 (59–75) | 0.302 |
| Site | |||
| Tongue | 31 (54) | 21 (70) | 0.209 |
| Floor of mouth | 19 (33) | 4 (13) | |
| Cheek | 3 (5) | 4 (13) | |
| Others | 4 (7) | 1 (3) | |
| pT status (7th TNM) | |||
| 1 | 50 (88) | 19 (63) | 0.012 |
| 2 | 7 (12) | 11 (37) | |
| Tumor infiltration depth (mm) | |||
| Median (IQR) | 3.5 (2.0–5.0) | 5.0 (3.6–7.0) | 0.007 |
| Tumor infiltration depth | |||
| <4.0 mm | 31 (54) | 9 (30) | 0.042 |
| ≥4.0 mm | 26 (46) | 21 (70) | |
| Perineural invasion | |||
| No | 55 (97) | 24 (80) | 0.018 |
| Yes | 2 (3) | 6 (20) | |
| Lymphovascular invasion | |||
| No | 53 (93) | 25 (83) | 0.265 |
| Yes | 4 (7) | 5 (17) | |
| Tumor grade | |||
| Well | 19 (33) | 6 (20) | 0.222 |
| Moderate | 38 (67) | 24 (80) | |
| Tumor pattern of invasion | |||
| Pushing | 42 (64) | 11 (37) | 0.001 |
| Infiltrative | 15 (25) | 19 (60) | |
| Cortactin | |||
| Low expression | 43 (75) | 18 (60) | 0.148 |
| High expression | 14 (25) | 12 (40) | |
| Cyclin D1 | |||
| Low expression | 26 (46) | 11 (37) | 0.497 |
| High expression | 31 (54) | 19 (63) | |
| FADD | |||
| Low expression | 39 (70) | 15 (50) | 0.101 |
| High expression | 17 (30) | 15 (50) | |
| RAB25 | |||
| Low expression | 23 (40) | 8 (27) | 0.245 |
| High expression | 34 (60) | 22 (73) | |
| S100A9 nuclear | |||
| Low expression | 17 (30) | 10 (33) | 0.809 |
| High expression | 40 (70) | 20 (67) | |
| S100A9 cytoplasmic | |||
| Low expression | 23 (40) | 10 (33) | 0.643 |
| High expression | 34 (60) | 20 (67) | |
Note: True N‐classification is determined by the combination of postoperative pathological lymph node classification (pN) combined with regional recurrence (false negatives). Four patients with a negative SLNB (pN0) were diagnosed with a regional recurrence and counted as true N positives. Molecular expression was dichotomized for cortactin, cyclin D1, RAB25, and S100A9 using a ROC‐analysis. FADD was semiquantitatively scored. In bold: significant different variables (p ≤ 0.05).
Abbreviations: IQR, interquartile range; TNM, American Joint Committee of Cancer TNM classification.