Materials and Methods
Study Design
Patients
Diagnosis, Treatment, and Follow-Up
Outcome Measures
Statistical Analyses
Results
Study Population
All | Young (<75 years) | Elderly (≥75 years) |
p value | ||||
---|---|---|---|---|---|---|---|
n = 3764 | (%) |
n = 2387 | (%) |
n = 1377 | (%) | ||
Age, years (mean [SD]) | 68.7 | [±11.8] | 62.3 | [9.9] | 80.0 | [3.8] |
<0.001
|
Sex | 0.058 | ||||||
Male | 2305 | (61) | 1489 | (62) | 816 | (59) | |
Female | 1459 | (39) | 898 | (38) | 561 | (41) | |
Malignancy history |
<0.001
| ||||||
No | 3265 | (87) | 2140 | (90) | 252 | (18) | |
Yes | 499 | (13) | 247 | (10) | 1125 | (82) | |
Referral for gastrectomy |
<0.001
| ||||||
No | 2720 | (80) | 1647 | (77) | 1073 | (86) | |
Yes | 659 | (20) | 481 | (23) | 178 | (14) | |
Unknown | 385 | 259 | 126 | ||||
Year of diagnosis |
<0.001
| ||||||
2006–2008 | 1317 | (35) | 807 | (34) | 510 | (37) | |
2009–2011 | 1229 | (33) | 747 | (31) | 482 | (35) | |
2012–2014 | 1218 | (32) | 833 | (35) | 385 | (28) | |
Neoadjuvant treatment |
<0.001
| ||||||
None | 2169 | (58) | 967 | (41) | 1202 | (87) | |
Chemotherapy | 1567 | (42) | 1400 | (59) | 167 | (12) | |
Radiotherapy | 4 | (0.1) | 0 | (0) | 4 | (0.3) | |
Chemoradiation | 24 | (0.6) | 20 | (0.8) | 4 | (0.3) | |
Surgical urgency |
0.014
| ||||||
(Sub)acute | 157 | (4) | 85 | (4) | 72 | (5) | |
Elective | 3607 | (96) | 2302 | (96) | 1305 | (95) | |
Surgical type |
<0.001
| ||||||
Subtotal gastrectomy | 2438 | (65) | 1438 | (60) | 1000 | (73) | |
Total gastrectomy | 1326 | (35) | 949 | (40) | 377 | (27) | |
Surgical approach |
0.032
| ||||||
Open | 3377 | (91) | 2120 | (90) | 1238 | (92) | |
Laparoscopic | 347 | (9) | 238 | (10) | 109 | (8) | |
Unknown | 40 | 29 | 30 | ||||
Radicality | 0.948 | ||||||
R0 | 3164 | (87) | 2006 | (87) | 1158 | (87) | |
R+ | 461 | (13) | 293 | (13) | 168 | (13) | |
Rx | 139 | 88 | 51 | ||||
(y)pT stage |
<0.001
| ||||||
T0 | 118 | (3) | 102 | (4) | 16 | (1) | |
T1 | 720 | (19) | 470 | (20) | 250 | (18) | |
T2 | 637 | (17) | 386 | (16) | 251 | (18) | |
T3 | 1434 | (39) | 900 | (38) | 534 | (39) | |
T4a | 811 | (22) | 494 | (21) | 317 | (23) | |
Tx | 44 | 35 | 9 | ||||
(y)pN stage | 0.729 | ||||||
N0 | 1856 | (49) | 1173 | (49) | 683 | (50) | |
N1 | 689 | (18) | 440 | (18) | 249 | (18) | |
N2 | 604 | (16) | 389 | (16) | 215 | (16) | |
N3 | 615 | (16) | 395 | (16) | 230 | (17) | |
Tumor differentiation |
<0.001
| ||||||
Well | 100 | (4) | 53 | (3) | 47 | (4) | |
Moderate | 722 | (27) | 366 | (23) | 356 | (32) | |
Poor | 1886 | (70) | 1165 | (74) | 721 | (64) | |
Undifferentiated | 1 | (<0.1) | 1 | (<0.1) | 0 | (0) | |
Unknown | 1055 | 802 | 253 | ||||
Adjuvant therapy |
<0.001
| ||||||
No | 2736 | (73) | 1433 | (60) | 1303 | (95) | |
Chemotherapy | 790 | (21) | 740 | (31) | 50 | (4) | |
Chemoradiation | 238 | (6) | 214 | (9) | 24 | (2) |
Lymph Node Yield
Young (<75 years) | Elderly (≥75 years) | |||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
<15 nodes | 15–25 nodes | >25 nodes | <15 nodes | 15–25 nodes | >25 nodes | |||||||||
n = 118) | (%) |
n = 707 | (%) |
n = 462 | (%) |
p value |
n = 851 | (%) |
n = 333 | (%) |
n = 174 | (%) |
p value | |
Age, years (mean [SD]) | 62.9 | [± 9.6] | 61.8 | [± 10.3] | 61.3 | [± 10.0] |
0.004
| 80.2 | [± 3.8] | 79.8 | [± 3.7] | 79.5 | [± 3.2] |
0.041
|
Sex | 0.254 |
0.017
| ||||||||||||
Male | 744 | (63) | 449 | (64) | 273 | (59) | 524 | (62) | 194 | (58) | 87 | (50) | ||
Female | 436 | (37) | 258 | (36) | 189 | (41) | 327 | (38) | 139 | (42) | 87 | (50) | ||
Malignancy history | 0.081 | 0.340 | ||||||||||||
No | 1042 | (88) | 643 | (91) | 422 | (91) | 686 | (81) | 275 | (83) | 148 | (85) | ||
Yes | 138 | (12) | 64 | (9) | 40 | (9) | 165 | (14) | 58 | (17) | 26 | (15) | ||
Referral for gastrectomy |
<0.001
|
<0.001
| ||||||||||||
No | 977 | (86) | 422 | (71) | 217 | (60) | 736 | (91) | 224 | (79) | 94 | (67) | ||
Yes | 154 | (14) | 176 | (29) | 144 | (40) | 73 | (9) | 59 | (21) | 46 | (33) | ||
Unknown | 49 | 109 | 101 | 42 | 50 | 34 | ||||||||
Year of diagnosis |
<0.001
|
<0.001
| ||||||||||||
2006–2008 | 525 | (44) | 181 | (26) | 68 | (15) | 387 | (45) | 85 | (26) | 20 | (12) | ||
2009–2011 | 408 | (35) | 211 | (30) | 124 | (27) | 313 | (37) | 115 | (34) | 53 | (30) | ||
2012–2014 | 247 | (21) | 315 | (45) | 270 | (58) | 151 | (18) | 133 | (40) | 101 | (58) | ||
Neoadjuvant treatment |
<0.001
|
0.008
| ||||||||||||
None | 581 | (49) | 234 | (33) | 130 | (28) | 764 | (90) | 278 | (83) | 142 | (82) | ||
Chemotherapy | 591 | (50) | 465 | (66) | 329 | (71) | 82 | (10) | 52 | (16) | 32 | (18) | ||
Radiotherapy | 0 | (1) | 0 | (1) | 0 | (1) | 2 | (0.2) | 2 | (0.6) | 0 | (0) | ||
Chemoradiation | 8 | 8 | 3 | 3 | (0.4) | 1 | (0.3) | 0 | (0) | |||||
Surgical urgency |
0.001
| 0.095 | ||||||||||||
(Sub)acute | 56 | (5) | 19 | (3) | 6 | (1) | 52 | (6) | 15 | (5) | 4 | (3) | ||
Elective | 1124 | (95) | 688 | (97) | 456 | (99) | 799 | (94) | 318 | (95) | 170 | (97) | ||
Surgical type |
<0.001
|
0.001
| ||||||||||||
Subtotal gastrectomy | 817 | (69) | 375 | (53) | 226 | (49) | 647 | (76) | 223 | (67) | 115 | (66) | ||
Total gastrectomy | 363 | (31) | 332 | (47) | 236 | (51) | 204 | (24) | 110 | (33) | 59 | (33) | ||
Surgical approach |
<0.001
|
<0.001
| ||||||||||||
Open | 1110 | (95) | 599 | (86) | 373 | (83) | 795 | (95) | 295 | (89) | 138 | (81) | ||
Laparoscopic | 58 | (5) | 101 | (14) | 79 | (18) | 41 | (5) | 36 | (11) | 32 | (19) | ||
Unknown | 12 | 7 | 10 | 15 | 2 | 4 | ||||||||
Radicality | 0.628 | 0.076 | ||||||||||||
R0 | 996 | (88) | 592 | (87) | 392 | (88) | 716 | (88) | 274 | (84) | 153 | (90) | ||
R+ | 138 | (12) | 92 | (13) | 52 | (12) | 97 | (12) | 53 | (16) | 17 | (10) | ||
Rx | 46 | 23 | 18 | 38 | 6 | 4 | ||||||||
(y)pT stage |
0.026
|
<0.001
| ||||||||||||
T0 | 47 | (4) | 34 | (5) | 18 | (4) | 8 | (1) | 7 | (2) | 1 | (0.6) | ||
T1 | 265 | (23) | 124 | (18) | 77 | (17) | 194 | (23) | 29 | (9) | 24 | (14) | ||
T2 | 198 | (17) | 118 | (17) | 63 | (14) | 163 | (19) | 58 | (18) | 24 | (14) | ||
T3 | 423 | (36) | 264 | (38) | 201 | (44) | 306 | (36) | 138 | (42) | 83 | (48) | ||
T4a | 232 | (20) | 151 | (22) | 100 | (22) | 173 | (21) | 99 | (30) | 42 | (24) | ||
Tx | 15 | 16 | 3 | 7 | 2 | 0 | ||||||||
(y)pN stage |
<0.001
|
<0.001
| ||||||||||||
N0 | 643 | (54) | 324 | (46) | 183 | (40) | 475 | (56) | 117 | (35) | 82 | (47) | ||
N1 | 247 | (21) | 117 | (17) | 70 | (15) | 162 | (19) | 64 | (19) | 18 | (10) | ||
N2 | 211 | (18) | 100 | (14) | 70 | (15) | 144 | (17) | 46 | (14) | 21 | (12) | ||
N3 | 79 | (7) | 166 | (23) | 139 | (30) | 70 | (8) | 106 | (32) | 51 | (31) | ||
Tumor differentiation |
<0.001
| 0.145 | ||||||||||||
Well | 35 | (4) | 8 | (2) | 9 | (3) | 35 | (5) | 9 | (3) | 3 | (2) | ||
Moderate | 217 | (27) | 98 | (21) | 48 | (16) | 230 | (33) | 83 | (29) | 38 | (28) | ||
Poor | 548 | (68) | 356 | (77) | 251 | (81) | 423 | (62) | 193 | (68) | 93 | (69) | ||
Undifferentiated | 1 | (0.1) | 0 | (0) | 0 | (0) | 0 | (0) | 0 | (0) | 0 | (0) | ||
Unknown | 379 | 245 | 154 | 163 | 48 | 40 | ||||||||
Adjuvant therapy |
<0.001
| 0.172 | ||||||||||||
No | 784 | (66) | 387 | (55) | 235 | (51) | 812 | (95) | 308 | (92) | 164 | (94) | ||
Chemotherapy | 314 | (27) | 245 | (35) | 171 | (37) | 29 | (3) | 16 | (5) | 5 | (3) | ||
Chemoradiation | 82 | (7) | 75 | (11) | 56 | (12) | 10 | (1) | 9 | (3) | 5 | (3) |
Postoperative Mortality
Young (<75 years) | 30-day mortality | 90-day mortality | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Univariable | Multivariablea
| Univariable | Multivariablea
| |||||||||
OR | 95% CI |
p value | OR | 95% CI |
p value | OR | 95% CI |
p value | OR | 95% CI |
p value | |
Each additional node | 0.99 | 0.97–1.02 | 0.445 | 0.99 | 0.96–1.02 | 0.521 | 0.99 | 0.97–1.01 | 0.183 | 0.99 | 0.96–1.01 | 0.298 |
<15 nodes | Ref | – |
–
| Ref | – | – | Ref | – | – | Ref | – | – |
15–25 nodes | 0.72 | 0.40–1.30 | 0.269 | 0.65 | 0.32–1.32 | 0.236 | 0.71 | 0.45–1.11 | 0.134 | 0.81 | 0.47–1.37 | 0.429 |
>25 nodes | 0.82 | 0.43–1.59 | 0.565 | 0.85 | 0.36–1.99 | 0.701 | 0.74 | 0.44–1.24 | 0.250 | 0.74 | 0.37–1.48 | 0.400 |
Elderly (≥75 years) | 30-day mortality | 90-day mortality | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Univariable | Multivariablea
| Univariable | Multivariablea
| |||||||||
OR | 95% CI |
p value | OR | 95% CI |
p value | OR | 95% CI |
p value | OR | 95% CI |
p value | |
Each additional node | 0.99 | 0.97–1.01 | 0.173 | 1.00 | 0.98–1.03 | 0.940 | 0.99 | 0.97–1.01 | 0.173 | 0.99 | 0.97–1.02 | 0.573 |
<15 nodes | Ref | – | – | Ref | – | – | Ref | – | – | Ref | – | – |
15–25 nodes | 0.85 | 0.59–1.22 | 0.367 | 0.94 | 0.56–1.58 | 0.823 | 0.85 | 0.59–1.22 | 0.367 | 0.87 | 0.55–1.36 | 0.538 |
>25 nodes | 0.66 | 0.38–1.14 | 0.132 | 0.74 | 0.34–1.60 | 0.442 | 0.66 | 0.38–1.14 | 0.132 | 0.63 | 0.32–1.23 | 0.178 |
Overall Survival
Young (<75 years) | Elderly (≥75 years) | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Univariable | Multivariablea
| Univariable | Multivariablea
| |||||||||
HR | 95% CI |
p value | HR | 95% CI |
p value | HR | 95% CI |
p value | HR | 95% CI |
p value | |
Lymph node yield | ||||||||||||
<15 nodes | Ref | – |
–
| Ref | – |
–
| Ref | – |
–
| Ref | – |
–
|
15–25 nodes | 0.97 | 0.85–1.11 | 0.68 | 0.71 | 0.60–0.83 |
<0.001
| 1.03 | 0.88–1.21 | 0.69 | 0.75 | 0.63–0.89 |
0.001
|
>25 nodes | 1.07 | 0.91–1.26 | 0.41 | 0.62 | 0.51–0.76 |
<0.001
| 0.83 | 0.67–1.04 | 0.10 | 0.61 | 0.47–0.80 |
<0.001
|
Additional year of age | 1.01 | 1.00–1.02 |
0.001
| 1.01 | 1.00–1.02 |
0.008
| 1.04 | 1.03–1.06 |
<0.001
| 1.03 | 1.02–1.05 |
<0.001
|
Sex | ||||||||||||
Male | Ref | – |
–
| Ref | – |
–
| Ref | – |
–
| Ref | – |
–
|
Female | 1.001 | 0.89–1.13 | 0.982 | 1.07 | 0.94–1.22 | 0.325 | 0.91 | 0.80–1.04 | 0.180 | 0.80 | 0.69–0.92 |
0.002
|
Malignancy history | ||||||||||||
No history of malignancy | Ref | – |
–
| Ref | – |
–
| Ref | – |
–
| Ref | – |
–
|
Malignancy in history | 1.21 | 1.01–1.45 |
0.043
| 1.20 | 0.98–1.46 | 0.076 | 1.21 | 1.03–1.42 |
0.021
| 1.38 | 1.15–1.64 |
<0.001
|
Referral | ||||||||||||
Same hospital | Ref | – |
–
| Ref | – |
–
| Ref | – |
–
| Ref | – |
–
|
Other hospital | 0.98 | 0.85–1.14 | 0.812 | 0.99 | 0.83–1.17 | 0.859 | 1.04 | 0.85–1.26 | 0.730 | 1.23 | 0.99–1.54 | 0.064 |
Additional year of diagnosis | 1.00 | 0.97–1.02 | 0.790 | 1.06 | 1.02–1.09 |
0.002
| 0.96 | 0.93–0.99 |
0.003
| 0.98 | 0.95–1.02 | 0.360 |
Tumor differentiation | ||||||||||||
Well | Ref | – |
–
| Ref | – |
–
| Ref | – |
–
| Ref | – |
–
|
Moderate | 1.88 | 1.12–3.13 |
0.016
| 0.97 | 0.57–1.65 | 0.897 | 1.07 | 0.72–0.60 | 0.739 | 0.84 | 0.55–1.28 | 0.415 |
Poor | 2.31 | 1.41–3.80 |
0.001
| 0.95 | 0.56–1.59 | 0.831 | 1.73 | 1.18–2.55 |
0.006
| 1.07 | 0.71–1.61 | 0.756 |
Undifferentiated | 3.95 | 0.52–29.8 | 0.182 | 0.87 | 0.51–1.48 | 0.608 | NA | NA | NA | NA | NA | NA |
Neoadjuvant therapy | ||||||||||||
None | Ref | – |
–
| Ref | – |
–
| Ref | – |
–
| Ref | – |
–
|
Chemotherapy | 0.83 | 0.74–0.93 |
0.001
| 1.10 | 0.93–1.29 | 0.264 | 0.63 | 0.50–0.79 |
<0.001
| 0.94 | 0.69–1.27 | 0.682 |
Chemoradiotherapy | 0.78 | 0.39–1.57 | 0.485 | 0.42 | 0.14–1.32 | 0.139 | 2.49 | 0.93–6.65 | 0.070 | 2.92 | 0.91–1.46 | 0.072 |
Surgical urgency | ||||||||||||
Elective | Ref | – |
–
| Ref | – |
–
| Ref | – |
–
| Ref | – |
–
|
(Sub)acute | 1.44 | 1.09–1.90 |
0.011
| 1.16 | 0.85–1.58 | 0.342 | 1.22 | 0.92–1.60 | 0.168 | 1.11 | 0.82–1.50 | 0.501 |
Type of surgery | ||||||||||||
Partial | Ref | – |
–
| Ref | – |
–
| Ref | – |
–
| Ref | – |
–
|
Total | 1.41 | 1.26–1.59 |
<0.001
| 1.27 | 1.11–1.45 |
<0.001
| 1.29 | 1.12–1.49 |
<0.001
| 1.25 | 1.07–1.46 |
0.005
|
Surgical approach | ||||||||||||
Open | Ref | – |
–
| Ref | – |
–
| Ref | – |
–
| Ref | – |
–
|
Minimally invasive | 0.93 | 0.73–1.18 | 0.54 | 0.98 | 0.72–1.33 | 0.901 | 0.88 | 0.65–1.18 | 0.391 | 0.96 | 0.64–1.45 | 0.849 |
Radicality | ||||||||||||
R0 | Ref | – |
–
| Ref | – |
–
| Ref | – |
–
| Ref | – |
–
|
R1 | 3.18 | 2.74–3.70 |
<0.001
| 1.65 | 1.39–1.96 |
<0.001
| 2.38 | 1.99–2.84 |
<0.001
| 0.45 | 1.18–1.77 |
<0.001
|
R2 | 6.60 | 4.13–10.5 |
<0.001
| 1.95 | 1.11–3.45 |
0.021
| 3.98 | 2.24–7.05 |
<0.001
| 2.32 | 1.20–4.48 |
0.012
|
(y)pT stage | ||||||||||||
T0 | Ref | – |
–
| Ref | – |
–
| Ref | – |
–
| Ref | – |
–
|
T1 | 1.17 | 0.67–2.06 | 0.579 | 1.07 | 0.57–2.02 | 0.839 | 1.22 | 0.50–3.00 | 0.655 | 0.91 | 0.32–2.60 | 0.854 |
T2 | 2.45 | 1.42–4.25 |
0.001
| 1.80 | 1.97–3.36 | 0.064 | 1.63 | 0.67–3.97 | 0.258 | 1.09 | 0.38–3.10 | 0.872 |
T3 | 5.34 | 3.14–9.08 |
<0.001
| 3.20 | 1.74–5.87 |
<0.001
| 3.03 | 1.25–7.32 |
0.014
| 1.57 | 0.56–4.43 | 0.396 |
T4a | 7.65 | 4.48–13.0 |
<0.001
| 3.68 | 1.96–6.81 |
<0.001
| 4.19 | 1.73–10.1 |
0.002
| 1.85 | 0.65–5.26 | 0.249 |
(y)pN stage | ||||||||||||
N0 | Ref | – |
–
| Ref | – |
–
| Ref | – |
–
| Ref | – |
–
|
N1 | 2.29 | 1.94–2.69 |
<0.001
| 1.71 | 1.43–2.06 |
<0.001
| 1.86 | 1.58–2.56 |
<0.001
| 1.60 | 1.31–1.96 |
<0.001
|
N2 | 3.28 | 2.79–3.85 |
<0.001
| 2.43 | 2.02–2.92 |
<0.001
| 2.54 | 2.11–3.05 |
<0.001
| 2.10 | 1.71–2.58 |
<0.001
|
N3a | 4.82 | 4.06–5.74 |
<0.001
| 3.65 | 2.97–4.48 |
<0.001
| 4.18 | 3.46–5.05 |
<0.001
| 3.26 | 2.59–4.10 |
<0.001
|
N3b | 8.99 | 8.99–7.10 |
<0.001
| 6.38 | 4.74–8.59 |
<0.001
| 5.02 | 3.65–6.90 |
<0.001
| 4.81 | 3.27–7.09 |
<0.001
|
Adjuvant therapy | ||||||||||||
None | Ref | – |
–
| Ref | – |
–
| Ref | – |
–
| Ref | – |
–
|
Chemotherapy | 0.71 | 0.62–0.81 |
<0.001
| 0.67 | 0.56–0.79 |
<0.001
| 0.53 | 0.35–0.82 |
0.005
| 0.73 | 0.43–1.23 | 0.241 |
Chemoradiotherapy | 0.94 | 0.77–1.16 | 0.575 | 0.70 | 0.56–0.88 |
0.002
| 0.94 | 0.57–1.57 | 0.825 | 0.43 | 0.24–0.78 |
0.005
|