Table 1. Baseline characteristics of patients who underwent SISH for EGFR and chromosome 7 and analysis of KRAS gene mutational status (a) and the subgroup of these patients that received anti-EGFR therapy with evaluable treatment response and sufficient follow up data (b).
| (a) Eligible patients for KRAS mutational status analysis, EGFR and chromosome 7 SISH analysis (n=80) |
(b) Patients treated with anti-EGFR therapy (n=54)
|
||
|---|---|---|---|
| KRAS WT and MT, n=80 | KRAS WT, n=44 | KRAS MT, n=10 | |
| n (%) | n (%) | n (%) | |
| Sex | |||
| Female | 34 (42) | 18 (40.9) | 6 (60) |
| Male | 46 (58) | 26 (59.1) | 4 (40) |
| Site of primary tumour | |||
| Colon | 51 (63.8) | 32 (72.7) | 6 (60) |
| Rectum | 28 (35) | 12 (27.3) | 4 (40) |
| Unknown | 1 (1.2) | ||
| Metastatic sites | |||
| Single | 28 (35) | 19 (43.2) | 2 (20) |
| Multiple | 52 (65) | 25 (56.8) | 8 (80) |
| Tumour differentiation grade | |||
| Grade 1 | 11 (13.8) | 6 (13.6) | 1 (10) |
| Grade 2 | 50 (62.5) | 28 (63.7) | 6 (60) |
| Grade 3 | 13 (16.2) | 6 (13.6) | 2 (20) |
| Unknown | 6 (7.5) | 4 (9.1) | 1 (10) |
| Follow-up data of the patients | |||
| Alive with disease | 16 (20) | 10 (22.7) | — |
| Alive and free of disease | 5 (6.2) | 1 (2.3) | — |
| Died of disease | 59 (73.8) | 33 (75) | 10 (100) |
| KRAS mutational status | |||
| KRAS WT | 54 (67.5) | 44 (100) | — |
| KRAS MT | 24 (30) | — | 10 (100) |
| Not evaluable | 2 (2.5) | — | — |
| Anti-EGFR treatment | |||
| Cetuximab | 51 (63.8) | 35 (79.5) | 10 (100) |
| Panitumumab | 10 (12.5) | 8 (18.2) | — |
| Both | 1 (1.2) | 1 (2.3) | — |
| None | 18 (22.5) | — | — |
| Line of therapy | |||
| First | 8 (12.9) | 5 (11.4) | 1 (10) |
| Second | 14 (22.6) | 12 (27.3) | — |
| Third or more | 40 (64.5) | 27 (61.3) | 9 (90) |
| Anti-EGFR combination therapy | |||
| Anti-EGFR combined to IRI | 46 (74.2) | 32 (72.7) | 9 (90) |
| Anti-EGFR combined to OXA | 10 (16.1) | 8 (18.2) | 1 (10) |
| Anti-EGFR combined to CAP | 2 (3.2) | 1 (2.3) | — |
| Single treatment | 4 (6.5) | 3 (6.8) | — |
Abbreviations: CAP=capecitabine; EGFR=epidermal growth factor receptor; IRI=irinotecan; MT=mutated; OXA=oxaliplatin; SISH=silver in situ hybridization; WT=wild type.