Table 1. Basic characteristics for the recruited participants in the primary training cohort (N = 235), internal validation cohort (N = 93), and external validation cohort (N = 84).
| Demographic or characteristic factor | Training cohort (N = 235) | Internal cohort (N = 93) | P-value* | External cohort (N = 84) | P-value# |
|---|---|---|---|---|---|
| Age, years (± SD) | 56.8 ± 11.2 | 58.7 ± 9.1 | 0.119 | 58.4 ± 11.9 | 0.298 |
| Sex (Male/Female) | 158/77 (67.2%/32.8%) | 54/39 (58.1%/41.9%) | 0.118 | 49/35 (58.3%/41.7%) | 0.142 |
| Tumor size, cm (± SD) | 2.75 ± 1.04 | 2.61 ± 1.17 | 0.323 | 3.09 ± 1.28 | 0.028 |
| Bismuth staging (I/II/IIIa/IIIb) | 17/52/56/110 (7.2%/22.1%/23.8%/46.8%) | 13/21/24/35 (14.0%/22.6%/25.8%/37.6%) | 0.284 | 2/13/32/37 (2.4%/15.5%/38.1%/44.0%) | 0.037 |
| Gazzaniga staging (I/II/III/IV) | 60/133/34/8 (25.5%/56.6%/14.5%/3.4%) | 18/55/20/0 (19.4%/59.1%/21.5%/0.0%) | 0.097 | 27/10/4/4 (60.0%/22.2%/8.9%/8.9%) | < 0.001 |
| MSKCC T staging (T1/T2/T3) | 179/25/31 (76.2%/10.6%/13.2%) | 75/7/11 (80.6%/7.5%/11.8%) | 0.628 | 29/10/6 (64.4%/22.2%/13.3%) | 0.093 |
| AJCC T staging (T1/T2/T3/T4) | 16/143/28/48 (6.8%/60.9%/11.9%/20.4%) | 2/61/15/15 (2.2%/65.6%/16.1%/16.1%) | 0.220 | 0/27/10/8 (0.0%/60.6%/22.2%/17.8%) | 0.104 |
| AJCC N staging (N0/N1-2) | 172/63 (73.2%/26.8%) | 67/26 (72.0%/28.0%) | 0.833 | 25/20 (55.6%/44.4%) | 0.018 |
| Differentiation (Low/Medium/High) | 26/199/10 (11.1%/84.7%/4.3%) | 1/90/2 (1.1%/96.8%/2.2%) | 0.007 | 7/33/5 (15.6%/73.3%/11.1%) | 0.103 |
| Portal vein invasion | |||||
| None | 178 (75.7%) | 75 (80.6%) | 56 (66.7%) | ||
| Ipsilateral portal vein branch | 25 (10.6%) | 7 (7.5%) | 9 (10.7%) | ||
| Bifurcation | 10 (4.3%) | 2 (2.2%) | 8 (9.5%) | ||
| Bifurcation plus portal vein branch | 10 (4.3%) | 2 (2.2%) | 5 (6.0%) | ||
| Main portal vein encasement | 13 (5.5%) | 7 (7.5%) | 0.571 | 6 (7.1%) | 0.355 |
| Hepatic artery invasion | |||||
| None | 203 (86.4%) | 70 (75.3%) | 62 (73.8%) | ||
| Hepatic artery branch | 26 (11.1%) | 19 (20.4%) | 22 (26.2%) | ||
| Main hepatic artery | 6 (2.6%) | 4 (4.3%) | 0.052 | 0 (0.0%) | 0.002 |
| Perineural invasion (No/Yes) | 116/119 (49.4%/50.6%) | 19/74 (20.4%/79.6%) | < 0.001 | 49/35 (58.3%/41.7%) | 0.158 |
| Liver invasion (No/Yes) | 208/27 (88.5%/11.5%) | 70/23 (75.3%/24.7%) | 0.003 | 67/17 (79.8%/20.2%) | 0.046 |
| Spigelian lobe resection (No/Yes) | 128/107 (54.5%/45.5%) | 53/40 (57.0%/43.0%) | 0.679 | 50/34 (59.5%/40.5%) | 0.423 |
| Radiotherapy (No/Yes) | 185/50 (78.7%/21.3%) | 82/11 (88.2%/11.8%) | 0.047 | 81/3 (96.4%/3.6%) | < 0.001 |
| Chemotherapy (No/Yes) | 187/48 (79.6%/20.4%) | 78/15 (83.9%/16.1%) | 0.373 | 76/8 (90.4%/9.6%) | 0.024 |
| Surgery treatment (R0/R1 or 2) | 177/58 (75.3%/24.7%) | 68/25 (73.1%/26.9%) | 0.679 | 59/25 (70.2%/29.8%) | 0.362 |
| ECOG status (0/1/2-3) | 19/138/78 (8.1%/58.7%/33.2%) | 3/62/28 (3.2%/66.7%/30.1%) | 0.199 | 21/47/16 (25.0%/56.0%/19.0%) | < 0.001 |
| CA19-9 level (≤73.5/73.6-325.0/≥325.1 U/ml) | 78/78/79 (33.2%/33.2%/33.6%) | 24/42/27 (25.8%/45.2%/29.0%) | 0.122 | 28/24/32 (33.3%/28.6%/38.1%) | 0.680 |
| Mayo Clinic (I/II/III-IV) | 12/107/116 (5.1%/45.5%/49.4%) | 0/46/47 (0%/49.5%/50.5%) | 0.083 | 6/19/59 (7.1%/22.6%/70.2%) | 0.001 |
| Vascular encasement (No/Yes) | 167/68 (71.1%/28.9%) | 63/30 (67.7%/32.3%) | 0.554 | 46/38 (54.8%/45.2%) | 0.007 |
| AJCC TNM staging (I/II/III/IV) | 14/113/54/54 (6.0%/48.1%/23.0%/23.0%) | 1/46/27/19 (1.1%/49.5%/29.0%/20.4%) | 0.197 | 5/23/33/23 (6.0%/27.4%/39.3%/27.4%) | 0.005 |
*
P-value for the comparison between training cohort and internal validation cohort.
#
P-value for the comparison between training cohort and external validation cohort.
Abbreviations: AJCC, American Joint Committee on Cancer; ECOG, Eastern Cooperative Oncology Group; MSKCC, Memorial Sloan Kettering Cancer Center; SD, Standard Deviation.