Table 2.
Patient Outcomes Within the Wild-Type KRAS and Mutated KRAS Patient Groups by Treatment and Age Groupa
|
mFOLFOX6 |
mFOLFOX6 + Cetuximab |
||||||
|---|---|---|---|---|---|---|---|
| Event | Age Group, y |
No. of Events/ Total No. |
3-Year % Event-Free (95% CI)b |
No. of Events/ Total No. |
3-Year % Event-Free (95% CI)b |
Hazard Ratio (95% CI)c |
P Valuec,d |
| Wild-type KRAS | |||||||
| Disease-free survival | All ages | 163/909 | 74.6 (71.1–78.3) | 192/954 | 71.5 (67.8–75.4) | 1.21 (0.98–1.49) | .08 |
| <70 | 141/797 | 74.5 (70.7–78.5) | 152/807 | 72.7 (68.8–76.9) | 1.13 (0.90–1.42) | .29 | |
| ≥70 | 22/112 | 75.3 (66.4–85.5) | 40/147 | 64.5 (55.3–75.4) | 1.59 (0.93–2.70) | .09 | |
| Overall survival | All ages | 78/909 | 87.3 (84.3–90.3) | 94/954 | 85.6 (82.7–88.7) | 1.25 (0.92–1.68) | .15 |
| <70 | 64/797 | 87.4 (84.2–90.7) | 62/807 | 88.4 (85.5–91.5) | 1.02 (0.72–1.44) | .92 | |
| ≥70 | 14/112 | 86.2 (78.9–94.1) | 32/147 | 72.5 (64.0–82.0) | 2.00 (1.05–3.78) | .03 | |
| Time-to-recurrence | All ages | 146/909 | 76.9 (73.4–80.4) | 165/954 | 74.4 (70.8–78.3) | 1.17 (0.93–1.46) | .18 |
| <70 | 128/797 | 76.6 (72.9–80.4) | 137/807 | 75.1 (71.2–79.2) | 1.13 (0.89–1.44) | .31 | |
| ≥70 | 18/112 | 79.0 (70.3–88.8) | 28/147 | 70.8 (61.3–81.6) | 1.36 (0.74–2.50) | .32 | |
| Mutated KRAS | |||||||
| Disease-free survival | All ages | 112/374 | 67.1 (61.8–72.8) | 111/343 | 65.0 (59.8–70.7) | 1.12 (0.86–1.46) | .38 |
| <70 | 91/320 | 67.5 (61.9–73.6) | 94/296 | 65.7 (60.1–71.8) | 1.14 (0.85–1.52) | .38 | |
| ≥70 | 21/54 | 64.3 (50.9–81.3) | 17/47 | 60.4 (46.8–78.0) | 1.23 (0.64–2.37) | .53 | |
| Overall survival | All ages | 44/374 | 87.9 (84.0–91.9) | 49/343 | 82.7 (78.0–87.6) | 1.27 (0.85–1.92) | .25 |
| <70 | 34/320 | 88.5 (84.3–92.8) | 37/296 | 84.7 (79.9–89.8) | 1.24 (0.77–1.98) | .38 | |
| ≥70 | 10/54 | 84.9 (75.1–96.0) | 12/47 | 68.9 (54.5–87.2) | 1.73 (0.74–4.07) | .21 | |
| Time-to-recurrence | All ages | 107/374 | 67.9 (62.6–73.6) | 101/343 | 67.0 (61.7–72.7) | 1.07 (0.81–1.40) | .63 |
| <70 | 87/320 | 68.5 (62.9–74.6) | 87/296 | 67.2 (61.6–73.3) | 1.10 (0.81–1.48) | .55 | |
| ≥70 | 20/54 | 64.3 (50.9–81.3) | 14/47 | 65.5 (51.6–83.1) | 1.05 (0.52–2.11) | .90 | |
| Mutated BRAF | |||||||
| Disease-free survival | All ages | 41/155 | 67.3 (59.3–76.3) | 51/192 | 68.9 (61.7–76.9) | 1.15 (0.76–1.75) | .50 |
| Overall survival | All ages | 30/155 | 74.8 (67.2–83.2) | 38/192 | 73.7 (66.4–81.9) | 1.21 (0.75–1.97) | .43 |
| Time-to-recurrence | All ages | 36/155 | 71.2 (63.4–79.9) | 44/192 | 71.9 (64.8–79.8) | 1.13 (0.72–1.76) | .59 |
| Wild-type BRAF and wild-type KRAS | |||||||
| Disease-free survival | All ages | 119/736 | 76.0 (72.0–80.2) | 138/743 | 72.0 (67.7–76.6) | 1.22 (0.96–1.56) | .11 |
| Overall survival | All ages | 47/736 | 90.1 (86.9–93.4) | 54/743 | 89.3 (86.3–92.4) | 1.22 (0.82–1.81) | .32 |
| Time-to-recurrence | All ages | 108/736 | 77.8 (73.9–81.8) | 119/743 | 74.9 (70.7–79.4) | 1.17 (0.90–1.52) | .23 |
Abbreviation: mFOLFOX6, the modified sixth version of the leucovorin, fluorouracil, and oxaliplatin regimen.
Within all patients having wild-type KRAS, 74.6% (95% CI, 71.1%–78.3%) and 71.5% (95% CI, 67.8%–75.4%) of patients were event free for disease-free survival following treatment with mFOLFOX6 and mFOLFOX6 with cetuximab, respectively. HR of more than 1 indicates the increase in risk associated with the addition of cetuximab and for the event listed for each row. The addition of cetuximab failed to reach statistical significance (disease-free survival: hazard ratio, 1.21; 95% CI, 0.98–1.49; P=.08).
Kaplan-Meier method estimate of the percentage of patients event-free (eg, disease-free, alive) at 3 years, with corresponding 95% CI.
Hazard ratio and P value reported from a multivariate Cox proportional hazards regression model, adjusted for number of nodes, histologic grade, and T stage.
By Wald statistic.