Table 2 Demographic and pathological characteristics of the 1730 patients in the current study
Characteristic | All patients | |
|---|---|---|
n | % | |
Sex | ||
 Male | 1250 | 72.3 |
 Female | 480 | 27.7 |
Age (years) | ||
 ≤ 60 | 1037 | 59.9 |
 > 60 | 693 | 40.1 |
Primary tumor site | ||
 Upper | 223 | 12.9 |
 Medium | 265 | 15.3 |
 Lower | 1188 | 68.7 |
 Mixed | 54 | 3.1 |
Size (cm) | ||
 ≤ 4.5 | 1016 | 58.7 |
 > 4.5 | 714 | 41.3 |
 Median (IQR, cm) | 4 (3–6) |  |
Histological type | ||
 Differentiated | 671 | 38.8 |
 Undifferentiated | 1059 | 61.2 |
8th UICC/AJCC T stage | ||
 T1 | 402 | 23.2 |
 T2 | 328 | 19.0 |
 T3 | 566 | 32.7 |
 T4a | 402 | 23.2 |
 T4b | 32 | 1.9 |
8th UICC/AJCC N stage | ||
 N0 | 812 | 46.9 |
 N1 | 331 | 19.1 |
 N2 | 294 | 17.0 |
 N3a | 212 | 12.3 |
 N3b | 81 | 4.7 |
8th UICC/AJCC TNM stage | ||
 IA | 344 | 19.9 |
 IB | 196 | 11.3 |
 IIA | 299 | 17.3 |
 IIB | 283 | 16.4 |
 IIIA | 340 | 19.7 |
 IIIB | 187 | 10.7 |
 IIIC | 81 | 4.7 |
LBVI | Â | Â |
 Present | 353 | 20.4 |
 Absent | 1187 | 68.6 |
 Unknown | 190 | 11.2 |
Number of examined LNs | ||
 ≤ 15 | 553 | 32.0 |
 > 15 | 1177 | 68.0 |
 Median (IQR) | 21 (13–32) |  |
 Mean ± SD | 23.8 ± 14.3 |  |
Number of metastatic LNs | ||
 Median (IQR) | 1 (0–4) |  |
 Mean ± SD | 3.3 ± 6.0 |  |