Table 3 The clinicopathologic features of KRAS-amplified and KRAS non-amplified metastatic colorectal carcinomas.
Clinical and pathologic features | KRAS-amplified, n = 15 (1%) | KRAS non-amplified, n = 1271 (99%) | p | KRAS-mutant, n = 563 (44%) | KRAS non-mutant, n = 723 (56%) | p |
|---|---|---|---|---|---|---|
Gender | n = 15 | n = 1256 | n = 553 | n = 718 | ||
Female | 3 (20%) | 568 (45%) | 0.066 | 258 (47%) | 313 (44%) | 0.280 |
Male | 12 (80%) | 688 (55%) | 295 (53%) | 405 (56%) | ||
Median age (range), years | 54.0 (26–78) | 64.0 (18–99) | 0.016 | 65.0 (18–91) | 63.0 (24–99) | 0.017a |
History of Lynch syndrome (n = 1201) | 0 (0%) | 10 (1%) | 1.000 | 5 (1%) | 5 (1%) | 0.754 |
History of IBD (n = 1201) | 9 (60%) | 14 (1%) | <0.001 | 6 (1%) | 17 (3%) | 0.135 |
Specimen sequenced | n = 15 | n = 1271 | n = 563 | n = 723 | ||
Primary | 2 (13%) | 371 (29%) | 0.255 | 128 (23%) | 245 (34%) | <0.001 |
Distant metastasis/recurrence | 13 (87%) | 900 (71%) | 435 (77%) | 478 (66%) | ||
Primary tumor site | n = 15 | n = 1256 | n = 553 | n = 718 | ||
Right colon | 4 (27%) | 466 (37%) | 0.592 | 230 (42%) | 240 (33%) | 0.003 |
Left colon | 11 (73%) | 790 (63%) | 323 (58%) | 478 (67%) | ||
Primary tumor grade | ||||||
Well-to-moderate | 12 (80%) | 1030 (82%) | 0.742 | 490 (89%) | 552 (77%) | <0.001 |
Poor-to-undifferentiated | 3 (20%) | 226 (18%) | 63 (11%) | 166 (23%) | ||
Primary tumor histology | ||||||
Conventional | 11 (73%) | 1049 (84%) | 0.136 | 445 (80%) | 615 (86%) | <0.001 |
Mucinous/mucinous features | 2 (13%) | 148 (12%) | 95 (17%) | 54 (7%) | ||
Signet-ring cell | 1 (7%) | 36 (3%) | 5 (1%) | 32 (4%) | ||
Micropapillary | 1 (7%) | 5 (<1%) | 2 (<1%) | 5 (1%) | ||
Adenosquamous/squamous | 0 (0%) | 2 (<1%) | 0 (0%) | 2 (<1%) | ||
Undifferentiated | 0 (0%) | 2 (<1%) | 1 (<1%) | 1 (<1%) | ||
Neuroendocrine | 0 (0%) | 11 (1%) | 5 (1%) | 6 (1%) | ||
Medullary | 0 (0%) | 3 (<1%) | 0 (0%) | 3 (<1%) | ||
Mismatch repair deficient (n = 1258) | 0 (0%) | 100 (8%) | 0.624 | 21 (4%) | 79 (11%) | <0.001 |
Mutations (excluding gene amplification)b | n = 15 | n = 1271 | n = 563 | n = 723 | ||
Negative | 9 (60%) | 500 (39%) | 0.117 | |||
KRAS | 5 (33%) | 558 (44%) | 0.448 | |||
NRAS | 0 (0%) | 29 (2%) | 1.000 | 1 (<1%) | 28 (4%) | <0.001 |
HRAS | 0 (0%) | 1 (<1%) | 1.000 | 0 (0%) | 1 (<1%) | 1.000 |
RAS (KRAS, NRAS, and HRAS) | 5 (33%) | 587 (46%) | 0.437 | |||
BRAF | 1 (7%) | 153 (12%) | 1.000 | 4 (1%) | 150 (21%) | <0.001 |
PIK3CA | 0 (0%) | 170 (13%) | 0.243 | 107 (19%) | 63 (9%) | <0.001 |
RAS/BRAF/PIK3CA | 6 (40%) | 771 (61%) | 0.117 | |||
