Introduction
Materials and methods
Patient enrollment and population
Study design
CT image acquisition parameters
CT-based radiomics analysis
Image segmentation
Radiomics features extraction
Model development
Radiomics models’ validation and comparison with the clinical conventional method
Protocols of treatment
Ascertainment of pDS
Statistical analysis
Results
Patient characteristics
Variables | Primary cohort (n = 206) | Testing cohort I (n = 40) | Testing cohort II (n = 46) | ||||||
---|---|---|---|---|---|---|---|---|---|
pDS | Non-pDS | p value | DS | Non-DS | p value | DS | Non-DS | p value | |
Gender | .723 | .215 | 1.000 | ||||||
Male | 59 (28.6) | 96 (46.6) | 9 (22.5) | 18 (45.0) | 12 (26.1) | 24 (52.2) | |||
Female | 18 ( 8.7) | 33 (16.1) | 7 (17.5) | 6 (15.0) | 3 (6.5) | 7 (15.2) | |||
Age | .737 | .272 | .267 | ||||||
≥ 65 | 25 (12.1) | 39 (18.9) | 2 (5.0) | 7 (17.5) | 4 (8.7) | 8 (17.4) | |||
< 65 | 52 (25.3) | 90 (43.7) | 14 (35.0) | 17 (42.5) | 11 (23.9) | 23 (50.0) | |||
Primary tumor site | .773 | .595 | .794 | ||||||
Fundus | 30 (14.6) | 46 (22.3) | 4 (10.0) | 9 (22.5) | 4 (8.7) | 9 (19.6) | |||
Body | 12 (5.8) | 24 (10.7) | 3 (7.5) | 6 (15.0) | 7 (15.2) | 11 (23.9) | |||
Antrum | 35 (17.0) | 59 (28.5) | 9 (22.5) | 9 (22.5) | 4 (8.7) | 11 (23.9) | |||
Differentiation | .001 | .048 | .049 | ||||||
Well | 7 (3.4) | 2 (0.1) | 1 (2.5) | 0 (0.0) | 2 (4.3) | 1 (0.2) | |||
Moderately | 30 (14.6) | 32 (15.5) | 7 (17.5) | 6 (15) | 5 (10.9) | 5 (10.9) | |||
Poorly | 39 (18.9) | 96 (46.5) | 6 (15.0) | 20 (50.0) | 6 (13.0) | 27 (58.7) | |||
Chemotherapy | .856 | .332 | .249 | ||||||
SEEOX | 57 (27.7) | 94 (45.6) | 11 (27.5) | 12 (30.0) | 7 (15.2) | 20 (43.5) | |||
SOX | 20 (9.7) | 35 (17.0) | 5 (12.5) | 12 (30.0) | 8 (17.4) | 11 (23.9) | |||
Gastrectomy* | .232 | .062 | .438 | ||||||
PG | 4 (2.1) | 1 (0.5) | 1 (2.7) | 0 (0.0) | 3 (6.5) | 2 (4.4) | |||
TG | 47 (24.6) | 70 (36.6) | 6 (16.2) | 15 (40.5) | 11 (23.9) | 26 (56.5) | |||
DG | 26 (13.6) | 43 (22.5) | 9 (24.3) | 6 (16.2) | 1 (2.2) | 3 (6.5) |
Primary cohort | Testing cohort I | Testing cohort II | |
---|---|---|---|
cTNM stage | |||
cT3N0M0 | 23 (11.2) | 2 (5.0) | 1 (2.2) |
cT3N+M0 | 58 (28.2) | 11 (27.5) | 7 (15.2) |
cT4aN0M0 | 28 (13.6) | 4 (10.0) | 2 (4.3) |
cT4aN+M0 | 90 (43.7) | 20 (50.0) | 34 (73.9) |
cT4bN+M0 | 7 (3.3) | 3 (7.5) | 2 (4.3) |
ypTNM stage | |||
ypT0N0M0 | 19 (9.2) | 4 (10.0) | 1 (2.2) |
ypT0N1M0 | 10 (4.9) | 1 (2.5) | 0 (0.0) |
ypT0N2M0 | 1 (0.5) | 1 (2.5) | 0 (0.0) |
ypT0N3M0 | 2 (1.0) | 1 (2.5) | 0 (0.0) |
ypT1N0M0 | 10 (4.9) | 0 (0.0) | 4 (8.7) |
ypT1N1M0 | 1 (0.5) | 0 (0.0) | 0 (0.0) |
ypT1N2M0 | 2 (1.0) | 2 (1.0) | 0 (0.0) |
ypT1N3M0 | 1 (0.5) | 0 (0.0) | 1 (2.2) |
ypT2N0M0 | 10 (4.9) | 4 (1.9) | 5 (10.9) |
ypT2N1M0 | 7 (3.4) | 1 (0.5) | 1 (2.2) |
ypT2N2M0 | 10 (4.9) | 2 (1.0) | 3 (6.5) |
ypT2N3M0 | 4 (1.9) | 0 (0.0) | 0 (0.0) |
ypT3N2M0 | 5 (2.4) | 0 (0.0) | 0 (0.0) |
ypT4aN0M0 | 38 (18.4) | 5 (2.4) | 8 (17.4) |
ypT4aN1M0 | 25 (12.1) | 3 (1.4) | 7 (15.2) |
ypT4aN2M0 | 23 (11.2) | 6 (2.9) | 7 (15.2) |
ypT4aN3M0 | 29 (14.1) | 6 (2.9) | 8 (17.4) |
ypT4b | 4 (1.9) | 1 (0.4) | 1 (2.2) |
M1 post-treatment | 5 (2.4) | 3 (1.5) | 0 (0.0) |
Performance of radiomics models
Radiomics models’ validation and comparison with the clinical method
Testing cohort I | Testing cohort II | |||||||
---|---|---|---|---|---|---|---|---|
PR | RESCIT | DR | Improved DR | PR | RECIST | DR | Improved DR | |
AUC | 0.750 | 0.750 | 0.922 | 0.961 | 0.889 | 0.617 | 0.850 | 0.921 |
(0.579–0.921) | (0.588–0.873) | (0.799–0.985) | (0.898–1) | (0.756–1) | (0.462–0.757) | (0.799–0.985) | (0.835–1) | |
p value | 0.009* | 0.001* | 0.000* | 0.000* | 0.000* | 0.056 | 0.000* | 0.000* |
SEN | 0.467 | 0.625 | 0.867 | 0.733 | 0.571 | 0.266 | 0.857 | 0.786 |
SPE | 0.958 | 0.875 | 0.917 | 1 | 0.966 | 0.968 | 0.862 | 0.966 |
ACC | 0.769 | 0.775 | 0.897 | 0.900 | 0.837 | 0.739 | 0.860 | 0.907 |