Characteristics | Center 1 n (%) | Center 2 n (%) | P |
---|---|---|---|
Gender | Â | Â | 0.243 |
 Male | 60(96.7) | 57(91.9) |  |
 Female | 2(3.3) | 5(8.1) |  |
Age (y) | Â | Â | 0.104 |
 Median; Range | 58; 42–75 | 64; 34–79 |  |
Smoking index | Â | Â | 0.442 |
 Median; Range | 600; 0–2000 | 800; 0–2400 |  |
Differentiation | Â | Â | 0.288 |
 Well | 2 (3.2) | 3 (6.4) |  |
 Moderate | 37 (59.7) | 44 (71) |  |
 Poor | 23 (37.1) | 15 (24.2) |  |
Extra nodal extension | Â | Â | 0.347 |
 Yes | 13 (21.0) | 9 (14.5) |  |
 No | 49 (79.0) | 53 (85.5) |  |
T stage | Â | Â | 0.002* |
 T1 | 3 (4.8) | 0 (0) |  |
  T2 | 9 (14.5) | 27 (43.5) |  |
  T3 | 40 (64.5) | 32 (51.6) |  |
 T4 | 10 (16.1) | 3 (4.8) |  |
N stage | Â | Â | 0.004* |
 N0 | 11 (17.7) | 30 (48.4) |  |
 N1 | 8 (12.9) | 5 (8.1) |  |
 N2 | 31 (50) | 21 (33.8) |  |
 N3 | 12 (19.4) | 6 (9.7) |  |
Stage (UICC 2017) |  |  |  < 0.001* |
 II | 1 (1.6) | 17 (27.4) |  |
 III | 14 (22.6) | 17 (27.4) |  |
 IVA | 34 (54.8) | 22 (35.5) |  |
 IVB | 13 (21) | 6 (9.7) |  |
Concurrent chemotherapy | Â | Â | Â |
 Yes | 27 (43.5) | 7 (11.3) |  < 0.001* |
 No | 35 (56.5) | 55 (88.7) |  |
CDDP prescription |  |  |  < 0.001* |
 100 mg/m2 every 3 weeks | 25 | 7 |  |
 − 40 mg/m2 each week | 2 | 0 |  |
Neck dissection | Â | Â | 0.001* |
 Ipsilateral | 10 (16.1) | 0 (0) |  |
 Bilateral | 52 (83.9) | 62 (100) |  |
Second primary cancer | 13 (21) | 8 (12.9) | 0.231 |
Total | 62 | 62 | NA |