Table 1.
Comparison of clinicopathological features between immune subgroups of 73 microsatellite instability-high colorectal cancers
| Variable | Immune-low (N=15) | Immune-intermediate (N=41) | Immune-high (N=17) | P value (overall) | P value (immune-low vs others) | P value (immune-low vs high) | |
| Age | Older (≥66 years) | 6 (40%) | 24 (59%) | 10 (59%) | 0.434 | 0.196 | 0.288 |
| Younger (<66 years) | 9 (60%) | 17 (41%) | 7 (41%) | ||||
| Sex | Male | 8 (53%) | 20 (49%) | 4 (24%) | 0.149 | 0.406 | 0.082 |
| Female | 7 (47%) | 21 (51%) | 13 (76%) | ||||
| Tumor location | Right-sided colon | 11 (73%) | 33 (80%) | 13 (76%) | 0.834 | 0.728 | 1 |
| Left-sided colon or rectum | 4 (27%) | 8 (20%) | 4 (24%) | ||||
| Gross tumor type | Polypoid or fungating | 9 (60%) | 26 (63%) | 11 (65%) | 0.96 | 0.786 | 0.784 |
| Ulceroinfiltrative | 6 (40%) | 15 (37%) | 6 (35%) | ||||
| Tumor size | Larger (≥6.2 cm) | 8 (53%) | 17 (41%) | 2 (12%) | 0.035 | 0.141 | 0.021 |
| Smaller (<6.2 cm) | 7 (47%) | 24 (59%) | 15 (88%) | ||||
| Depth of invasion (pT) | Within the proper muscle (pT1/pT2) | 0 (0%) | 7 (17%) | 4 (24%) | 0.154 | 0.105 | 0.104 |
| Beyond the proper muscle (pT3/pT4) | 15 (100%) | 34 (83%) | 13 (76%) | ||||
| Lymph node metastasis (pN) | Absent (pN0) | 10 (67%) | 31 (76%) | 13 (76%) | 0.768 | 0.516 | 0.699 |
| Present (pN1/pN2) | 5 (33%) | 10 (24%) | 4 (24%) | ||||
| Distant metastasis or early recurrence | Absent | 10 (67%) | 38 (93%) | 17 (100%) | 0.006 | 0.008 | 0.015 |
| Present | 5 (33%) | 3 (7%) | 0 (0%) | ||||
| Lymphatic invasion | Absent | 10 (67%) | 31 (76%) | 10 (59%) | 0.427 | 0.76 | 0.647 |
| Present | 5 (33%) | 10 (24%) | 7 (41%) | ||||
| Venous invasion | Absent | 15 (100%) | 36 (88%) | 15 (88%) | 0.367 | 0.332 | 0.486 |
| Present | 0 (0%) | 5 (12%) | 2 (12%) | ||||
| Perineural invasion | Absent | 12 (80%) | 33 (80%) | 14 (82%) | 0.983 | 1 | 1 |
| Present | 3 (20%) | 8 (20%) | 3 (18%) | ||||
| Tumor grade (differentiation) | Low-grade (well or moderately differentiated) | 13 (87%) | 27 (66%) | 9 (53%) | 0.124 | 0.121 | 0.06 |
| High-grade (poorly differentiated) | 2 (13%) | 14 (34%) | 8 (47%) | ||||
| Mucinous histology | Non-mucinous carcinoma | 4 (27%) | 34 (83%) | 17 (100%) | <0.001 | <0.001 | <0.001 |
| Mucinous carcinoma | 11 (73%) | 7 (17%) | 0 (0%) | ||||
| Medullary histology | Absent | 15 (100%) | 33 (80%) | 9 (53%) | 0.005 | 0.031 | 0.003 |
| Present | 0 (0%) | 8 (20%) | 8 (47%) | ||||
| Signet ring cell histology | Absent | 10 (67%) | 35 (85%) | 17 (100%) | 0.031 | 0.041 | 0.015 |
| Present | 5 (33%) | 6 (15%) | 0 (0%) | ||||
| Tumor budding | Low (BD1) or intermediate (BD2) | 10 (67%) | 33 (80%) | 11 (65%) | 0.354 | 0.516 | 0.907 |
| High (BD3) | 5 (33%) | 8 (20%) | 6 (35%) | ||||
| Poorly differentiated clusters | Grade 1 or 2 | 9 (60%) | 28 (68%) | 5 (29%) | 0.024 | 0.828 | 0.082 |
| Grade 3 | 6 (40%) | 13 (32%) | 12 (71%) |