Background
Methods
Patients
Endpoints and follow-up
Computer-aided unsupervised clustering method
Statistical analyses
Results
Patients
Variable | Subgroups | Frequency (%) |
---|---|---|
Age at diagnosis (Mean ± SD) | 57.49 ± 11.32 | |
Gender | Male | 1738 (72.00) |
Female | 676 (28.00) | |
Tumor size(Mean ± SD) | 5.66 ± 3.08 | |
Site of tumor | Whole stomach | 174 (7.21) |
Upper stomach | 263 (10.89) | |
Middle stomach | 248 (10.27) | |
Lower stomach | 1243 (51.49) | |
> 2/3 stomach | 486 (20.13) | |
Pathological tumour stage (%) | T1 | 342 (14.17) |
T2 | 1136 (47.06) | |
T3 | 515 (21.33) | |
T4a | 208 (8.62) | |
T4b | 213 (8.82) | |
Pathological nodal stage (%) | N0 | 884 (36.62) |
N1 | 451 (18.68) | |
N2 | 530 (21.96) | |
N3 | 549 (22.74) | |
TNM stage (%) | IA | 272 (11.27) |
IB | 394 (16.32) | |
IIA | 391 (16.20) | |
IIB | 371 (15.37) | |
IIIA | 399 (16.53) | |
IIIB | 237 (9.82) | |
IIIC | 116 (4.81) | |
IV | 234 (9.69) | |
Gross type (%) | Borrmann I | 26 (1.17) |
Borrmann II | 384 (17.25) | |
Borrmann III | 1558 (70.02) | |
Borrmann IV | 257 (11.55) | |
Surgery (%) | Absolutely curative | 1116 (46.23) |
Relatively curative | 819 (33.93) | |
Palliative | 479 (19.84) | |
Lymph node dissection (%) | D1 | 238 (9.86) |
D2 | 1584 (65.62) | |
D3 | 204 (8.45) | |
Palliative resection | 388 (16.07) | |
Complication (%) | Intestinal obstruction | 56 (2.32) |
Anastomotic leakage | 32 (1.33) | |
Pneumonia | 9 (0.4) | |
Abdominal abscess | 39 (1.62) | |
Anaemia | 16 (0.7) | |
Other | 83 (3.44) | |
Hepatic metastasis (%) | 72 (2.98) | |
Peritoneum metastasis (%) | 178 (7.37) | |
Adjunctive therapy (%) | 475 (19.68) | |
Type of gastrectomy (%) | Total | 403 (16.69) |
Subtotal | 2011 (83.31) | |
Combined organ resection (%) | Pancreas or spleen | 159 (6.59) |
Liver or gall | 78 (3.23) | |
Transverse colon | 214 (8.86) | |
Other | 68 (2.82) | |
Diagnosis period | 1980s | 496 (20.5) |
1990s | 673 (27.9) | |
2000s | 1245 (51.6) |
Univariable analyses | Multivariable analyses | |||
---|---|---|---|---|
HR (95% CI) |
p
a
| HR (95% CI) |
p
b
| |
Age (years) | 0.005 | 0.301 | ||
≤ 55 | 1 (Ref) | 1 (Ref) | ||
> 55 | 1.180 (1.052–1.322) | 0.005 | 1.066 (0.944–1.204) | 0.301 |
Sex | 0.801 | 0.937 | ||
Women | 1 (Ref) | 1 (Ref) | ||
Men | 1.016 (0.897–1.151) | 0.801 | 0.995 (0.872–1.135) | 0.937 |
Tumor size | 0.000 | 0.000 | ||
≤ 4 cm | 1 (Ref) | 1 (Ref) | ||
5–8 cm | 2.101 (1.848–2.389) | 0.000 | 1.256 (1.091–1.446) | 0.001 |
≥ 9 cm | 3.694 (3.152–4.328) | 0.000 | 1.372 (1.117–1.686) | 0.003 |
Tumour site | 0.000 | 0.000 | ||
Whole stomach | 1 (Ref) | 1 (Ref) | ||
Upper stomach | 0.499 (0.399–0.624) | 0.000 | 1.097 (0.828–1.453) | 0.519 |
Middle stomach | 0.324 (0.253–0.415) | 0.000 | 0.919 (0.691–1.223) | 0.562 |
Lower stomach | 0.316 (0.263–0.379) | 0.000 | 0.749 (0.5814–0.966) | 0.026 |
> 2/3 stomach | 0.512 (0.420–0.623) | 0.000 | 0.774 (0.6110–0.979) | 0.033 |
Gross appearance | 0.000 | 0.000 | ||
Borrmann types I | 1 (Ref) | 1 (Ref) | ||
Borrmann types II | 0.553 (0.331–0.924) | 0.024 | 0.562 (0.331–0.954) | 0.033 |
Borrmann types III | 0.864 (0.527–1.417) | 0.563 | 0.833 (0.498–1.392) | 0.485 |
Borrmann types IV | 1.856 (1.116–3.087) | 0.017 | 0.970 (0.571–1.648) | 0.911 |
Tumour stage | 0.000 | 0.002 | ||
T1 | 1 (Ref) | 1 (Ref) | ||
T2 | 8.192 (5.560–12.069) | 0.000 | 3.897 (1.716–8.850) | 0.001 |
T3 | 15.017 (10.151–22.216) | 0.000 | 4.409 (1.894–10.262) | 0.001 |
T4a | 21.388 (14.039–32.585) | 0.000 | 5.901 (2.433–14.317) | 0.000 |
T4b | 31.140 (20.876–46.452) | 0.000 | 5.720 (2.382–13.734) | 0.000 |
Lymph-node stage | 0.000 | 0.003 | ||
N0 | 1 (Ref) | 1 (Ref) | ||
N1 | 1.710 (1.443–2.026) | 0.000 | 1.042 (0.839–1.294) | 0.710 |
N2 | 2.163 (1.847–2.535) | 0.000 | 1.061 (0.831–1.354) | 0.636 |
N3 | 3.462 (2.976–4.027) | 0.000 | 1.462 (1.122–1.905) | 0.005 |
TNM stage | 0.000 | 0.000 | ||
IA | 1 (Ref) | 1 (Ref) | ||
IB | 5.046 (3.140–8.110) | 0.000 | 1.095 (0.402–2.984) | 0.859 |
IIA | 7.889 (4.966–12.531) | 0.000 | 1.397 (0.503–3.881) | 0.521 |
IIB | 11.514 (7.265–18.250) | 0.000 | 1.709 (0.594–4.913) | 0.320 |
IIIA | 15.752 (9.982–24.857) | 0.000 | 1.830 (0.627–5.337) | 0.269 |
IIIB | 18.880 (11.853–30.074) | 0.000 | 1.775 (0.595–5.296) | 0.304 |
IIIC | 34.931 (21.597–56.497) | 0.000 | 2.016 (0.641–6.346) | 0.231 |
IV | 45.506 (28.699–72.155) | 0.000 | 1.593 (0.455–5.580) | 0.467 |
Surgery | 0.000 | 0.000 | ||
Absolutely curative | 1 (Ref) | 1 (Ref) | ||
Relatively curative | 2.025 (1.763–2.325) | 0.000 | 1.203 (1.030–1.406) | 0.020 |
Palliative | 5.815 (5.051–6.693) | 0.000 | 2.422 (1.755–3.341) | 0.000 |
Lymph node dissection | 0.000 | 0.150 | ||
D1 | 1 (Ref) | 1 (Ref) | ||
D2 | 0.867 (0.711–1.058) | 0.161 | 0.815 (0.652–1.019) | 0.072 |
D3 | 0.839 (0.639–1.101) | 0.206 | 0.830 (0.615–1.119) | 0.221 |
Palliative resection | 3.323 (2.687–4.111) | 0.000 | 0.677 (0.502–0.914) | 0.011 |
Joint organ removal | 0.000 | 0.020 | ||
None | 1 (Ref) | 1 (Ref) | ||
Pancreas or spleen | 2.125 (1.744–2.590) | 0.000 | 1.229 (0.972–1.553) | 0.085 |
Liver or gall | 1.722 (1.291–2.296) | 0.000 | 1.093 (0.773–1.546) | 0.615 |
Transverse colon | 2.227 (1.879–2.641) | 0.000 | 1.300 (1.061–1.593) | 0.011 |
Other | 2.907 (2.206–3.830) | 0.000 | 1.278 (0.947–1.724) | 0.109 |
Gastrectomy | 0.000 | 0.603 | ||
Total | 1 (Ref) | 1 (Ref) | ||
Subtotal | 0.522 (0.457–0.596) | 0.000 | 1.050 (0.874–1.261) | 0.603 |
Hepatic metastasis | 0.000 | 0.037 | ||
No | 1 (Ref) | 1 (Ref) | ||
Yes | 4.548 (3.555–5.818) | 0.000 | 1.769 (1.035–3.023) | 0.037 |
Peritoneum metastasis | 0.000 | 0.004 | ||
No | 1 (Ref) | 1 (Ref) | ||
Yes | 4.190 (3.547–4.948) | 0.000 | 1.525 (0.837–2.780) | 0.168 |
Adjunctive therapy | 0.000 | 0.001 | ||
No | 1 (Ref) | 1 (Ref) | ||
Yes | 0.720 (0.612–0.846) | 0.000 | 0.766 (0.638–0.919) | 0.004 |
Diagnosis period | 0.004 | 0.023 | ||
1980s | 1 (Ref) | 1 (Ref) | ||
1990s | 0.948 (0.817–1.100) | 0.479 | 0.903 (0.767–1.063) | 0.220 |
2000s | 0.823 (0.714–0.948) | 0.007 | 0.846 (0.702–1.020) | 0.080 |
Computer-aided unsupervised clustering: tumor size
Computer-aided unsupervised clustering: number of lymph node metastases
Computer-aided unsupervised clustering: TNM stage
UICC | Clustering | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
No. | TNM | No. | TNM | |||||||||
IA | 272 | (100)1 | IA | 340 | (100)1 | (110)3 | (120)6 | |||||
IB | 394 | (200)2 | (110)3 | IB | 363 | (200)2 | ||||||
IIA | 391 | (300)4 | (210)5 | (120)6 | IIA | 558 | (210)5 | (220)9 | (410)11 | (500)14 | ||
IIB | 371 | (400)7 | (310)8 | (220)9 | (130)10 | IIB | 301 | (300)4 | (310)8 | (320)12 | ||
IIIA | 399 | (410)11 | (320)12 | (230)13 | IIIA | 453 | (400)7 | (130)10 | (230)13 | (330)17 | (221)27 | |
IIIB | 237 | (500)14 | (510)15 | (420)16 | (330)17 | IIIB | 82 | (420)16 | (530)19 | (211)26 | (411)34 | |
IIIC | 116 | (520)18 | (530)19 | (430)20 | IIIC | 199 | (520)18 | (430)20 | (301)29 | (311)30 | (321)31 | |
(331)32 | (421)35 | (431)36 | (501)37 | (511)38 | ||||||||
IV | 234 | (101)21 | (111)22 | (121)23 | (131)24 | IV | 118 | (510)15 | (201)25 | (521)39 | (531)40 | (401)33 |
(201)25 | (211)26 | (221)27 | (231)28 | |||||||||
(301)29 | (311)30 | (321)31 | (331)32 | |||||||||
(401)33 | (411)34 | (421)35 | (431)36 | |||||||||
(501)37 | (511)38 | (521)39 | (531)40 |
Effect of TNM stage on prognosis predictions after unsupervised clustering
IA vs. IB | IB vs. IIA | IIA vs. IIB | IIB vs. IIIA | IIIA vs. IIIB | IIIB vs. IIIC | IIIC vs. IV | Average | |
---|---|---|---|---|---|---|---|---|
UICC | 2.66e-14 | 1.79e-04 | 2.07e-04 | 1.20e-03 | 8.61e-02 | 5.46e-06 | 2.99e-02 | 0.0168 |
Clustering | 0 | 1.00e-04 | 1.31e-06 | 2.60e-04 | 1.73e-02 | 1.16e-04 | 161e-04 | 0.0030 |