Gastric cancer (GC) is the third leading cause of cancer-related mortality and the fifth most common cancer globally [
Researches have indicated that PGC differed from DGC in clinicopathological characteristics [
Given the suggested but undecided differences in clinicopathological characteristics and prognosis between PGC and DGC, the aim of our study was to compare the clinicopathological features, prognostic factors, and survival outcomes between PGC and DGC based on the China National Cancer Center Gastric Cancer Database (NCCGCDB) in order to determine whether PGC conveys worse prognosis and provides evidence for the development of guiding strategies for GC patients with different tumor locations.
All the study data were abstracted from the NCCGCDB. The NCCGCDB was a clinical gastric cancer database based on a huge retrospective cohort, which was sourced from China National Cancer Center, a single but large-volume institution, and included more than 19,000 patients from all around China from 1997 to 2018. PGC was defined as tumors with the epicenter located in cardia (C16.0) or fundus (C16.1), whereas DGC was defined as lesions of the body (C16.2), antrum (C16.3), or pylorus (C16.4). Changing trends in clinicopathological characteristics and OS of total GC, PGC, and DGC were analyzed in four consecutive time periods: from 1997 to 2002 (period 1), from 2002 to 2007 (period 2), from 2007 to 2012 (period 3), and from 2012 to 2017 (period 4). The geographical locations of these gastric cancer patients can be found in Figure
The geographical locations of PGC and DGC patients of NCCGCDB, 1997–2017.
Categorical variables were compared using the Chi-squared test and continuous variables were analyzed by Student’s
In this study, 16,119 patients were included. The clinicopathological features of 9,640 patients (59.8%) with DGC and 6,479 patients (41.2%) with PGC were compared (Table
Clinicopathological characteristics by tumor location.
Total GC | PGC | DGC | | |
---|---|---|---|---|
| | | ||
| ||||
Mean (SD) | 58.5 (11.4) | 61.5 (10.0) | 56.4 (11.9) | <0.001 |
Younger (≤35) | 590 (3.7) | 86 (1.3) | 504 (5.2) | |
Middle-aged (36-65) | 10,842 (67.3) | 4,026 (62.1) | 6,816 (70.7) | |
Older (≥66) | 4,685 (29.1) | 2,366 (36.5) | 2,319 (24.1) | <0.001 |
| ||||
Male | 4,171 (25.9) | 5,374 (82.9) | 6,574 (68.2) | |
Female | 11,948 (74.1) | 1,105 (17.1) | 3,066 (31.8) | <0.001 |
| ||||
Never smokers | 9,289 (57.6) | 3,065 (47.3) | 6,224 (64.6) | |
Smokers | 6,621 (41.1) | 3,352 (51.7) | 3,269 (33.9) | <0.001 |
Current smokers | 4,634 (28.8) | 2,210 (34.1) | 2,424 (25.2) | |
Ex-smokers | 1,987 (12.3) | 1,142 (17.6) | 845 (8.8) | <0.001 |
| ||||
Never drinkers | 10,398 (64.5) | 3,716 (57.4) | 6,682 (69.3) | |
Drinkers | 5,496 (34.1) | 2,699 (41.7) | 2,797 (29.0) | <0.001 |
Current drinkers | 4,752 (29.5) | 2,416 (37.3) | 2,336 (24.2) | |
Ex-drinkers | 744 (4.6) | 283 (4.4) | 461 (4.8) | <0.001 |
| ||||
<18.5 | 1,066 (6.6) | 380 (5.9) | 686 (7.1) | |
18.5-22.9 | 6,097 (37.8) | 2,301 (35.5) | 3,796 (39.4) | |
23-27.4 | 6,576 (40.8) | 2,760 (42.6) | 3,816 (39.6) | |
≥27.5 | 2,028 (12.6) | 909 (14.0) | 1,119 (11.6) | <0.001 |
| ||||
No | 1,247 (7.7) | 437 (6.7) | 625 (6.5) | |
Yes | 956 (5.9) | 331 (5.1) | 810 (8.4) | |
Unknown | 13,916 (86.3) | 5,711 (88.2) | 8,205 (85.1) | <0.001 |
| ||||
T0+Tis | 58 (0.4) | 14 (0.2) | 44 (0.5) | |
T1 | 2,491 (15.5) | 596 (9.2) | 1,895 (19.7) | |
T2 | 1,376 (8.5) | 441 (6.8) | 935 (9.7) | |
T3 | 3,019 (18.7) | 1,640 (25.3) | 1,379 (14.3) | |
T4 | 6,288 (39.0) | 2,573 (39.7) | 3,715 (38.5) | |
TX | 2,887 (17.9) | 1,215 (18.8) | 1,672 (17.3) | <0.001 |
| ||||
N0 | 4,538 (28.2) | 1,623 (25.1) | 2,915 (30.2) | |
N1 | 2,281 (14.1) | 983 (15.2) | 1,298 (13.5) | |
N2 | 2,417 (15.0) | 1,081 (16.7) | 1,336 (13.9) | |
N3 | 3,759 (23.3) | 1,489 (23.0) | 2,270 (23.6) | |
NX | 3,124 (19.4) | 1,303 (20.1) | 1,821 (18.9) | <0.001 |
| ||||
M0 | 13,629 (84.6) | 5,555 (85.7) | 8,074 (83.8) | |
M1 | 1,883 (11.7) | 651 (10.1) | 1,232 (12.8) | <0.001 |
| ||||
0 | 52 (0.3) | 13 (0.2) | 39 (0.4) | |
I | 2,989 (18.5) | 825 (12.7) | 2,164 (22.5) | |
II | 2,112 (13.1) | 929 (14.3) | 1,183 (12.3) | |
III | 7,354 (45.6) | 3,272 (50.5) | 4,082 (42.3) | |
IV | 1,883 (11.7) | 651 (10.1) | 1,232 (12.8) | <0.001 |
| ||||
Intestinal | 2,390 (14.8) | 1,215 (18.8) | 1,175 (12.2) | |
Diffuse | 2,202 (13.7) | 555 (8.6) | 1,647 (17.1) | |
Mixed | 1,486 (9.2) | 592 (9.1) | 894 (9.3) | |
Unknown | 10,041 (62.3) | 4,117 (63.5) | 5,924 (61.5) | <0.001 |
| ||||
Gastrectomy | 13,190 (81.8) | 5,260 (81.2) | 7,930 (82.3) | |
No surgery | 2,929 (18.2) | 1,219 (18.8) | 1,710 (17.7) | 0.068 |
| ||||
Negative | 12,457 (77.3) | 4,950 (76.4) | 7,507 (77.9) | |
Positive on the proximal margin | 183 (1.1) | 91 (1.4) | 92 (1.0) | |
Positive on the distal margin | 197 (1.2) | 74 (1.1) | 123 (1.3) | |
Positive on the proximal and distal margin | 46 (0.3) | 12 (0.2) | 34 (0.4) | 0.002 |
| ||||
0 (-) | 2,850 (17.7) | 1,037 (16.0) | 1,813 (18.8) | |
1 (+) | 2,620 (16.3) | 971 (15.0) | 1,649 (17.1) | |
2 (++) | 1,082 (6.7) | 466 (7.2) | 616 (6.4) | |
3 (+++) | 522 (3.2) | 275 (4.2) | 247 (2.6) | |
Unknown | 9,045 (56.1) | 3,730 (57.6) | 5,315 (55.1) | <0.001 |
| ||||
No | 15,670 (97.2) | 6,286 (97.0) | 9,384 (97.3) | |
Yes | 110 (0.7) | 31 (0.5) | 79 (0.8) | 0.024 |
| ||||
Borrmann I | 1,160 (7.2) | 714 (11.0) | 446 (4.6) | |
Borrmann II | 4,605 (28.6) | 1,926 (29.7) | 2,679 (27.8) | |
Borrmann III | 3,843 (23.8) | 1,574 (24.3) | 2,269 (23.5) | |
Borrmann IV | 981 (6.1) | 347 (5.4) | 634 (6.6) | |
Unknown | 1,807 (11.2) | 696 (10.7) | 1,111 (11.5) | <0.001 |
GC, gastric cancer; PGC, proximal gastric cancer; DGC, distal gastric cancer; SD, standard deviation.
As for tumors, PGC patients were more likely to be in later pT stage (pT3 and pT4, 65.0% versus 52.8%,
Changing trends of clinicopathological features in GC patients were analyzed. The proportion of pT1 tumors increased gradually with time, from 9.5% in period 1 to 22.0% in period 4, whereas the proportion of pT4 had declined from 66.0% in period 1 to 28.1% in period 4. The proportion of patients with pN0 increased from 24.5% in period 1 to 33.5% in period 4, whereas patients with pN3 were gradually decreased from 26.3% in period 1 to 21.5% in period 4. The proportion of pM1 remained relatively stable (from 11.2% to 10.7%) during the past 20 years. In pTNM stage, a significant increase was observed in stages I and II (from 12.0% and 3.8% in period 1 to 24.9% and 17.6% in period 4, resp.), while the proportion of stage III had declined from 63.0% in period 1 to 37.2% in period 4.
As shown in Table
Univariate survival analysis by tumor location.
Prognostic Factors | PGC group (N=4,716) | DGC group (N=7,228) | PGC versus DGC | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
HR | 95% CI | | HR | 95% CI | | HR | 95% CI | | ||||
Lower | Upper | Lower | Upper | Lower | Upper | |||||||
| ||||||||||||
Younger (≤35) | 1.00 | 1.00 | 2.20 | 1.50 | 3.22 | <0.001 | ||||||
Middle-aged (36-65) | 0.47 | 0.33 | 0.65 | <0.001 | 0.94 | 0.77 | 1.14 | 0.52 | 1.12 | 1.03 | 1.21 | 0.008 |
Older (≥66) | 0.51 | 0.37 | 0.72 | <0.001 | 1.01 | 0.82 | 1.24 | 0.92 | 1.14 | 1.01 | 1.28 | 0.028 |
| ||||||||||||
Male | 1.00 | 1.00 | 1.16 | 1.08 | 1.25 | <0.001 | ||||||
Female | 1.04 | 0.91 | 1.19 | 0.55 | 1.07 | 0.98 | 1.17 | 0.12 | 1.13 | 0.98 | 1.30 | 0.097 |
| ||||||||||||
Never smoker | 1.00 | 1.00 | 1.08 | 0.99 | 1.18 | 0.074 | ||||||
Smokers | 1.00 | 0.91 | 1.10 | 0.98 | 0.85 | 0.78 | 0.93 | <0.001 | 1.27 | 1.15 | 1.41 | <0.001 |
Current smokers | 1.03 | 0.92 | 1.14 | 0.63 | 0.89 | 0.81 | 0.99 | 0.023 | 1.25 | 1.11 | 1.40 | <0.001 |
Ex-smokers | 0.94 | 0.82 | 1.09 | 0.41 | 0.72 | 0.60 | 0.86 | <0.001 | 1.39 | 1.13 | 1.71 | 0.002 |
| ||||||||||||
Never drinkers | 1.00 | 1.00 | 1.11 | 1.03 | 1.21 | 0.009 | ||||||
Drinkers | 0.95 | 0.86 | 1.05 | 0.35 | 0.85 | 0.77 | 0.94 | 0.001 | 1.24 | 1.11 | 1.39 | <0.001 |
Current drinkers | 0.97 | 0.87 | 1.07 | 0.55 | 0.90 | 0.82 | 1.00 | 0.048 | 1.19 | 1.06 | 1.34 | 0.004 |
Ex-drinkers | 0.82 | 0.62 | 1.07 | 0.14 | 0.58 | 0.45 | 0.74 | <0.001 | 1.55 | 1.08 | 2.23 | 0.017 |
| ||||||||||||
<18.5 | 1.24 | 1.02 | 1.51 | 0.033 | 1.12 | 0.96 | 1.32 | 0.16 | 1.33 | 1.06 | 1.68 | 0.016 |
18.5-22.9 | 1.00 | 1.00 | 1.21 | 1.09 | 1.34 | <0.001 | ||||||
23-27.4 | 0.73 | 0.65 | 0.82 | <0.001 | 0.82 | 0.75 | 0.91 | <0.001 | 1.07 | 0.96 | 1.19 | 0.22 |
≥27.5 | 0.79 | 0.67 | 0.92 | 0.0024 | 0.73 | 0.63 | 0.85 | <0.001 | 1.30 | 1.08 | 1.57 | 0.006 |
| ||||||||||||
No | 1.00 | 1.00 | 1.55 | 1.09 | 2.21 | 0.016 | ||||||
Yes | 1.45 | 1.01 | 2.08 | 0.044 | 1.71 | 1.25 | 2.33 | 0.001 | 1.31 | 0.95 | 1.81 | 0.095 |
Unknown | 2.36 | 1.80 | 3.09 | <0.001 | 3.31 | 2.60 | 4.21 | <0.001 | 1.10 | 1.03 | 1.18 | 0.005 |
| ||||||||||||
T0+Tis | 3.28 | 0.79 | 13.58 | 0.10 | 2.58 | 0.94 | 7.08 | 0.066 | 2.46 | 0.45 | 13.53 | 0.30 |
T1 | 1.00 | 1.00 | 2.07 | 1.39 | 3.10 | <0.001 | ||||||
T2 | 1.58 | 1.02 | 2.45 | 0.041 | 3.26 | 2.38 | 4.46 | <0.001 | 0.96 | 0.67 | 1.38 | 0.84 |
T3 | 3.86 | 2.77 | 5.38 | <0.001 | 8.32 | 6.39 | 10.83 | <0.001 | 0.92 | 0.80 | 1.06 | 0.26 |
T4 | 6.69 | 4.83 | 9.28 | <0.001 | 12.61 | 9.81 | 16.21 | <0.001 | 1.05 | 0.95 | 1.15 | 0.37 |
TX | 11.12 | 7.99 | 15.48 | <0.001 | 27.37 | 21.21 | 35.31 | <0.001 | 0.81 | 0.72 | 0.92 | <0.001 |
| ||||||||||||
N0 | 1.00 | 1.00 | 1.65 | 1.35 | 2.02 | <0.001 | ||||||
N1 | 1.91 | 1.56 | 2.36 | <0.001 | 2.39 | 1.96 | 2.90 | <0.001 | 1.31 | 1.07 | 1.60 | <0.001 |
N2 | 2.84 | 2.34 | 3.44 | <0.001 | 3.89 | 3.26 | 4.65 | <0.001 | 1.20 | 1.01 | 1.41 | 0.034 |
N3 | 5.00 | 4.20 | 5.95 | <0.001 | 8.42 | 7.21 | 9.83 | <0.001 | 0.97 | 0.86 | 1.08 | 0.56 |
NX | 6.56 | 5.51 | 7.81 | <0.001 | 12.60 | 10.79 | 14.73 | <0.001 | 0.85 | 0.76 | 0.96 | 0.007 |
| ||||||||||||
M0 | 1.00 | 1.00 | 1.28 | 1.18 | 1.38 | <0.001 | ||||||
M1 | 4.96 | 4.33 | 5.68 | <0.001 | 7.45 | 6.73 | 8.25 | <0.001 | 0.85 | 0.73 | 0.98 | 0.027 |
| ||||||||||||
0 | 4.06 | 0.99 | 16.71 | 0.052 | 2.25 | 0.71 | 7.14 | 0.17 | 3.16 | 0.53 | 19.05 | 0.21 |
I | 1.00 | 1.00 | 2.04 | 1.42 | 2.94 | <0.001 | ||||||
II | 2.26 | 1.63 | 3.15 | <0.001 | 4.43 | 3.35 | 5.86 | <0.001 | 1.03 | 0.81 | 1.29 | 0.84 |
III | 6.39 | 4.79 | 8.52 | <0.001 | 12.28 | 9.64 | 15.64 | <0.001 | 1.03 | 0.94 | 1.12 | 0.58 |
IV | 23.33 | 17.19 | 31.68 | <0.001 | 54.77 | 42.63 | 70.38 | <0.001 | 0.85 | 0.73 | 0.98 | 0.027 |
| ||||||||||||
Intestinal | 1.00 | 1.00 | 1.68 | 1.31 | 2.15 | <0.001 | ||||||
Diffuse | 1.93 | 1.54 | 2.42 | <0.001 | 2.09 | 1.66 | 2.62 | <0.001 | 1.54 | 1.25 | 1.90 | <0.001 |
Mixed | 1.54 | 1.22 | 1.94 | 0.0003 | 1.37 | 1.04 | 1.81 | 0.024 | 1.88 | 1.45 | 2.46 | <0.001 |
Unknown | 2.76 | 2.35 | 3.24 | <0.001 | 4.45 | 3.64 | 5.44 | <0.001 | 1.05 | 0.97 | 1.13 | 0.22 |
| ||||||||||||
Early stage | 1.00 | 1.00 | 2.09 | 1.31 | 3.32 | 0.002 | ||||||
LAGC | 5.29 | 3.65 | 7.65 | <0.001 | 9.18 | 7.24 | 13.04 | <0.001 | 1.09 | 1.01 | 1.19 | 0.032 |
Distant | 25.33 | 17.25 | 37.20 | <0.001 | 60.25 | 44.52 | 81.52 | <0.001 | 0.85 | 0.73 | 0.98 | 0.027 |
| ||||||||||||
Gastrectomy | 1.00 | 1.00 | 1.24 | 1.15 | 1.34 | <0.001 | ||||||
No surgery | 3.01 | 2.71 | 3.35 | <0.001 | 4.47 | 4.08 | 4.88 | <0.001 | 0.84 | 0.74 | 0.94 | 0.002 |
| ||||||||||||
Negative | 1.00 | 1.00 | 1.27 | 1.17 | 1.38 | <0.001 | ||||||
Positive on the proximal margin | 1.96 | 1.34 | 2.87 | 0.0006 | 2.98 | 2.07 | 4.28 | <0.001 | 0.81 | 0.48 | 1.37 | 0.43 |
Positive on the distal margin | 2.49 | 1.63 | 3.79 | <0.001 | 2.56 | 1.85 | 3.53 | <0.001 | 1.25 | 0.74 | 2.12 | 0.40 |
Positive on the proximal and distal margin | 1.08 | 0.27 | 4.34 | 0.91 | 2.57 | 1.33 | 4.95 | 0.005 | 0.60 | 0.13 | 2.80 | 0.51 |
| ||||||||||||
0 (-) | 1.00 | 1.00 | 1.45 | 1.22 | 1.73 | <0.001 | ||||||
1 (+) | 0.70 | 0.57 | 0.86 | 0.001 | 0.85 | 0.72 | 1.02 | 0.073 | 1.19 | 0.98 | 1.46 | 0.083 |
2 (++) | 0.69 | 0.53 | 0.89 | 0.005 | 0.66 | 0.51 | 0.85 | 0.002 | 1.54 | 1.11 | 2.12 | 0.01 |
3 (+++) | 0.94 | 0.71 | 1.26 | 0.68 | 0.99 | 0.72 | 1.38 | 0.96 | 1.38 | 0.93 | 2.07 | 0.11 |
Unknown | 1.72 | 1.49 | 1.98 | <0.001 | 2.44 | 2.15 | 2.77 | <0.001 | 1.03 | 0.95 | 1.11 | 0.49 |
| ||||||||||||
No | 1.00 | 1.00 | 1.15 | 1.08 | 1.23 | <0.001 | ||||||
Yes | 2.44 | 1.44 | 4.12 | 0.001 | 2.37 | 1.63 | 3.44 | <0.001 | 1.22 | 0.64 | 2.33 | 0.54 |
| ||||||||||||
Borrmann I | 1.00 | 1.00 | 1.03 | 0.78 | 1.35 | 0.85 | ||||||
Borrmann II | 1.03 | 0.85 | 1.24 | 0.79 | 0.93 | 0.73 | 1.17 | 0.52 | 1.14 | 1.00 | 1.30 | 0.045 |
Borrmann III | 1.14 | 0.94 | 1.38 | 0.20 | 1.13 | 0.90 | 1.43 | 0.30 | 1.03 | 0.90 | 1.17 | 0.71 |
Borrmann IV | 2.16 | 1.70 | 2.75 | <0.001 | 2.11 | 1.63 | 2.73 | <0.001 | 1.05 | 0.84 | 1.31 | 0.67 |
Unknown | 2.44 | 1.99 | 3.01 | <0.001 | 3.09 | 2.44 | 3.93 | <0.001 | 0.81 | 0.69 | 0.94 | 0.007 |
| ||||||||||||
PGC | 1.00 | |||||||||||
DGC | 0.87 | 0.82 | 0.93 | <0.001 |
The univariate analysis found a survival benefit in patients with DGC (HR = 0.87, 95% CI: 0.82-0.93). After stratification by pTNM stage, further comparison between the two groups showed that, compared to patients with DGC, PGC patients had a worse survival outcome in stage I (HR = 2.04, 95% CI: 1.42-2.94) but a better prognosis in stage IV (HR = 0.85, 95% CI: 0.73-0.98). There was no significant survival difference in stages II and III (
When appropriate significant factors were taken into consideration, multivariate analysis (Table
Multivariate survival analysis by tumor location.
Prognostic | Total (n=11,944) | PGC group (n=4,716) | DGC group (n=7,228) | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
HR | 95% CI | P Value | HR | 95% CI | P Value | HR | 95% CI | P Value | ||||
Lower | Upper | Lower | Upper | Lower | Upper | |||||||
| ||||||||||||
Never drinkers | 1.00 | 1.00 | 1.00 | |||||||||
Current drinkers | 0.94 | 0.87 | 1.01 | 0.08 | 0.98 | 0.88 | 1.09 | 0.69 | 0.90 | 0.81 | 0.99 | 0.034 |
Ex-drinkers | 0.74 | 0.61 | 0.89 | 0.002 | 0.81 | 0.62 | 1.07 | 0.14 | 0.72 | 0.56 | 0.93 | 0.012 |
| ||||||||||||
<18.5 | 1.07 | 0.95 | 1.22 | 0.26 | 1.29 | 1.06 | 1.58 | 0.011 | 0.96 | 0.82 | 1.13 | 0.61 |
18.5-22.9 | 1.00 | 1.00 | 1.00 | |||||||||
23-27.4 | 0.89 | 0.83 | 0.96 | 0.002 | 0.80 | 0.71 | 0.90 | <0.001 | 0.96 | 0.88 | 1.06 | 0.44 |
≥27.5 | 0.91 | 0.82 | 1.01 | 0.09 | 0.94 | 0.80 | 1.09 | 0.41 | 0.87 | 0.75 | 1.01 | 0.07 |
| ||||||||||||
No | 1.00 | 1.00 | 1.00 | |||||||||
Yes | 1.43 | 1.13 | 1.81 | 0.003 | 1.35 | 0.94 | 1.94 | 0.11 | 1.52 | 1.11 | 2.07 | 0.009 |
Unknown | 1.73 | 1.44 | 2.08 | <0.001 | 1.62 | 1.23 | 2.13 | <0.001 | 1.82 | 1.43 | 2.33 | <0.001 |
| ||||||||||||
T0+Tis | 1.66 | 0.72 | 3.85 | 0.23 | 2.36 | 0.56 | 9.94 | 0.24 | 1.47 | 0.52 | 4.17 | 0.46 |
T1 | 1.00 | 1.00 | 1.00 | |||||||||
T2 | 1.53 | 1.05 | 2.24 | 0.028 | 0.82 | 0.41 | 1.62 | 0.57 | 1.89 | 1.19 | 3.00 | 0.007 |
T3 | 2.65 | 1.86 | 3.76 | <0.001 | 1.47 | 0.79 | 2.73 | 0.22 | 3.20 | 2.08 | 4.91 | <0.001 |
T4 | 3.28 | 2.32 | 4.64 | <0.001 | 1.99 | 1.08 | 3.69 | 0.028 | 3.77 | 2.47 | 5.75 | <0.001 |
TX | 2.97 | 2.02 | 4.36 | <0.001 | 1.46 | 0.76 | 2.81 | 0.26 | 3.88 | 2.42 | 6.23 | <0.001 |
| ||||||||||||
N0 | 1.00 | 1.00 | 1.00 | |||||||||
N1 | 1.36 | 1.17 | 1.59 | <0.001 | 1.36 | 1.09 | 1.69 | 0.007 | 1.37 | 1.10 | 1.69 | 0.0041 |
N2 | 1.99 | 1.73 | 2.30 | <0.001 | 1,98 | 1.61 | 2.44 | <0.001 | 2.00 | 1.65 | 2.44 | <0.001 |
N3 | 3.44 | 3.01 | 3.92 | <0.001 | 3.29 | 2.70 | 4.01 | <0.001 | 3.58 | 2.99 | 4.28 | <0.001 |
NX | 1.83 | 1.41 | 2.38 | <0.001 | 1.60 | 1.04 | 2.48 | 0.034 | 1.91 | 1.36 | 2.67 | <0.001 |
| ||||||||||||
M0 | 1.00 | 1.00 | 1.00 | |||||||||
M1 | 3.05 | 2.59 | 3.59 | <0.001 | 3.65 | 2.75 | 4.86 | <0.001 | 2.84 | 2.32 | 3.48 | <0.001 |
| ||||||||||||
Intestinal | 1.00 | 1.00 | 1.00 | |||||||||
Diffuse | 1.22 | 1.03 | 1.43 | 0.018 | 1.21 | 0.95 | 1.55 | 0.12 | 1.32 | 1.04 | 1.67 | 0.024 |
Mixed | 0.99 | 0.83 | 1.19 | 0.94 | 1.06 | 0.83 | 1.35 | 0.65 | 0.96 | 0.73 | 1.27 | 0.78 |
Unknown | 1.30 | 1.11 | 1.52 | <0.001 | 1.20 | 0.97 | 1.49 | 0.095 | 1.44 | 1.14 | 1.82 | 0.003 |
| ||||||||||||
Gastrectomy | 1.00 | 1.00 | 1.00 | |||||||||
No surgery | 1.43 | 1.22 | 1.67 | <0.001 | 1.48 | 1.15 | 1.90 | 0.003 | 1.44 | 1.17 | 1.76 | <0.001 |
| ||||||||||||
Negative | 1.00 | 1.00 | 1.00 | |||||||||
Positive on the proximal margin | 1.49 | 1.14 | 1.94 | 0.004 | 1.24 | 0.84 | 1.83 | 0.29 | 1.67 | 1.16 | 2.41 | 0.006 |
Positive on the distal margin | 1.54 | 1.19 | 1.99 | 0.001 | 1.53 | 1.00 | 2.34 | 0.051 | 1.57 | 1.13 | 2.17 | 0.007 |
Positive on the proximal and distal margin | 0.95 | 0.52 | 1.72 | 0.85 | 0.70 | 0.17 | 2.82 | 0.62 | 1.10 | 0.57 | 2.14 | 0.77 |
| ||||||||||||
0 (-) | 1.00 | 1.00 | 1.00 | |||||||||
1 (+) | 0.97 | 0.85 | 1.10 | 0.62 | 0.82 | 0.67 | 1.01 | 0.06 | 1.08 | 0.91 | 1.29 | 0.37 |
2 (++) | 0.92 | 0.76 | 1.11 | 0.39 | 0.80 | 0.61 | 1.04 | 0.09 | 1.02 | 0.78 | 1.33 | 0.88 |
3 (+++) | 1.16 | 0.93 | 1.45 | 0.19 | 1.13 | 0.84 | 1.52 | 0.43 | 1.15 | 0.82 | 1.61 | 0.42 |
Unknown | 1.33 | 1.17 | 1.50 | <0.001 | 1.19 | 0.98 | 1.45 | 0.07 | 1.44 | 1.23 | 1.70 | <0.001 |
| ||||||||||||
No | 1.00 | 1.00 | 1.00 | |||||||||
Yes | 1.37 | 1.01 | 1.86 | 0.045 | 2.13 | 1.25 | 3.65 | 0.006 | 1.18 | 0.81 | 1.73 | 0.38 |
| ||||||||||||
Borrmann I | 1.00 | 1.00 | 1.00 | |||||||||
Borrmann II | 0.92 | 0.80 | 1.07 | 0.30 | 0.87 | 0.72 | 1.06 | 0.17 | 0.99 | 0.78 | 1.25 | 0.93 |
Borrmann III | 0.98 | 0.84 | 1.14 | 0.75 | 0.90 | 0.74 | 1.10 | 0.29 | 1.06 | 0.83 | 1.35 | 0.62 |
Borrmann IV | 1.44 | 1.21 | 1.71 | <0.001 | 1.44 | 1.12 | 1.85 | 0.005 | 1.48 | 1.14 | 1.93 | 0.003 |
Unknown | 1.12 | 0.95 | 1.32 | 0.17 | 1.05 | 0.84 | 1.32 | 0.68 | 1.19 | 0.93 | 1.52 | 0.17 |
| ||||||||||||
PGC | 1.00 | |||||||||||
DGC | 0.94 | 0.88 | 1.00 | 0.058 |
The changing trends of 5-year OS and PFS for PGC and DGC patients were shown in Figure
(a) The changing trends of 5-year OS of PGC and DGC from period 1 to period 4. (b) The changing trends of PFS of PGC and DGC from period 1 to period 4.
There was also an increase in PFS of PGC and DGC groups during the 20 years (Figure
In this study, the clinicopathological characteristics of PGC patients presented differently with DGC patients. Although two groups were predominantly males, PGC had a greater proportion of males than DGC. This was similar to some previous reports [
In addition, our study demonstrated that PGC presented to be more frequent in older patients as compared to DGC, which was similar to two published Chinese reports [
A primary finding of our study was that PGC was not independently associated with overall mortality, although it has long been thought to confer worse prognosis [
Interestingly, the multivariate analyses reported that BMI was an independent prognostic factor for PGC patients but not for DGC patients. Moreover, a higher BMI was associated with survival benefits, while a lower BMI was associated with higher mortality, which has not been described previously. Our study also identified that no gastrectomy was an adverse independent predictor for both PGC and DGC patients, suggesting that surgery was necessary to improve survival outcomes for resected GC. Today, systematic D2 lymphadenectomy with the goal of complete (R0) resection is a generally recognized as standard surgical procedure for gastric cancer.
Our study found that 5-year survival increased significantly during the 20 years for total GC, PGC, and DGC, with an increase of 34.3%, 36.3%, and 32.3%, respectively. This was in a concord with the changing trends of increased stages I and II, as well as the decreased lymph node. Relative survival improved steadily over time for gastric cancer, suggesting an improvement in the quality of clinical services for gastric cancer patients, such as improved access to primary healthcare, greater availability of diagnostic facilities, and improved effectiveness of the multimodal treatment [
One limitation of this study was that it was just conducted in a single institution, so the results might not represent the whole Chinese population. However, the volume of PGC and DGC patients was large and the source of patients usually came from the area of Northern and Eastern China, which might serve as a reference for a large population-based study.
In conclusion, PGC significantly differed from DGC in clinicopathological characteristics and prognosis factors. However, there was no significant relationship between survival outcome and gastric tumor location.
The data used to support the findings of this study are included within the article in Tables
The authors declare that there are no conflicts of interest.
Lulu Zhao and Huang Huang contributed equally to this work. All authors made substantial contributions to the intellectual content of this paper.
This study was funded in part by the National Key R&D Program of China (Grant no. 2017YFC0908300).