Table II.
Associations between KIT mutations and clinicopathological characteristics of patients with GISTs (n=302).
| KIT exon11 mutation, n (%) | KIT mutation, n (%) | |||||
|---|---|---|---|---|---|---|
| Characteristics | Deletion (n=110) | Substitution (n=79) | P-value | Del 557/558/559 (n=86) | Others (n=147) | P-value |
| Sex | ||||||
| Male | 57 (51.8) | 37 (46.8) | 0.499 | 48 (55.8) | 74 (50.3) | 0.419 |
| Female | 53 (48.2) | 42 (53.2) | 38 (44.2) | 73 (49.7) | ||
| Age (years) | ||||||
| ≤60 | 51 (46.4) | 30 (38.0) | 0.250 | 40 (46.5) | 62 (42.2) | 0.520 |
| >60 | 59 (53.6) | 49 (62.0) | 46 (53.5) | 85 (57.8) | ||
| Site | ||||||
| Gastric | 67 (60.9) | 58 (73.4) | 0.073 | 54 (62.8) | 93 (63.3) | 0.942 |
| Non-gastric | 43 (39.1) | 21 (26.6) | 32 (37.2) | 54 (36.7) | ||
| Tumor dimension (cm) | ||||||
| ≤2 | 15 (13.6) | 15 (19.0) | 0.051 | 12 (14.0) | 24 (16.3) | 0.449 |
| >2 to ≤ 5 | 44 (40.0) | 42 (53.2) | 34 (39.5) | 64 (43.5) | ||
| >5 to ≤10 | 30 (27.3) | 16 (20.3) | 22 (25.6) | 40 (27.2) | ||
| >10 | 21 (19.1) | 6 (7.6) | 18 (20.9) | 19 (12.9) | ||
| Mitotic count (/50HPFa) | ||||||
| ≤5 | 68 (61.8) | 66 (83.5) | 0.001 | 50 (58.1) | 117 (79.6) | <0.001 |
| >5 | 42 (38.2) | 13 (16.5) | 36 (41.9) | 30 (20.4) | ||
| Necrosis | ||||||
| Present | 35 (31.8) | 12 (15.2) | 0.009 | 27 (31.4) | 33 (22.4) | 0.132 |
| Absent | 75 (68.2) | 67 (84.8) | 59 (68.6) | 114 (77.6) | ||
| Morphology | ||||||
| Spindle | 97 (88.2) | 75 (94.9) | 0.246 | 74 (86.0) | 137 (93.2) | 0.072 |
| Epithelioid | 1 (0.9) | 0 (0.0) | 1 (1.2) | 1 (0.7) | ||
| Mixed | 12 (10.9) | 4 (5.1) | 11 (12.8) | 9 (6.1) | ||
| Risk stratification | ||||||
| Not highb | 66 (60.0) | 64 (81.0) | 0.002 | 50 (58.1) | 106 (72.1) | 0.029 |
| High | 44 (40.0) | 15 (19.0) | 36 (41.9) | 41 (27.9) | ||
| WHO grade | ||||||
| 1/2/3a/4 | 68 (61.8) | 63 (79.7) | 0.008 | 50 (58.1) | 110 (74.8) | 0.008 |
| 3b/5/6a/6b | 42 (38.2) | 16 (20.3) | 36 (41.9) | 37 (25.2) | ||
a
Equal to 5 mm2
b
very low/low/intermediate. GISTs, gastrointestinal stromal tumors; KIT, KIT proto-oncogene, receptor tyrosine kinase; HPF, high-power fields; WHO, World Health Organization.