Table 3.
Univariate Analysis of Survival among Patients with Stage II or Stage III Colon Cancer According to Microsatellite-Instability Status or Adjuvant-Chemotherapy Status.*
| Analysis | No. of Patients | Patients Surviving at 5 Yr | P Value | Patients Surviving without Disease at 5 Yr | P Value |
|---|---|---|---|---|---|
| % (95% CI) | % (95% CI) | ||||
| According to microsatellite-instability status | |||||
|
| |||||
| All patients | 570 | ||||
| Stability or low-frequency instability | 475 | 71.9 (67.9–76.1) | 0.07 | 64.1 (59.9–68.6) | 0.04 |
| High-frequency instability | 95 | 78.4 (70.3–87.3) | 75.3 (67.0–84.6) | ||
|
| |||||
| Patients receiving no adjuvant chemotherapy | 287 | ||||
| Stability or low-frequency instability | 245 | 68.4 (62.7–74.6) | 0.004 | 58.7 (52.8–65.3) | 0.004 |
| High-frequency instability | 42 | 88.0 (78.7–98.4) | 82.9 (72.1–95.3) | ||
|
| |||||
| Patients receiving adjuvant chemotherapy | 283 | ||||
| Stability or low-frequency instability | 230 | 75.5 (70.1–81.4) | 0.66 | 69.8 (64.1–76.0) | 0.85 |
| High-frequency instability | 53 | 70.7 (59.2–84.5) | 69.3 (57.8–83.1) | ||
|
| |||||
| According to adjuvant-chemotherapy status | |||||
| All patients | 570 | ||||
| Adjuvant chemotherapy | 283 | 74.6 (69.6–80.0) | 0.12 | 69.7 (64.5–75.3) | 0.06 |
| No adjuvant chemotherapy | 287 | 71.2 (66.1–76.8) | 62.3 (56.9–68.2) | ||
|
| |||||
| Stability or low-frequency instability | 475 | ||||
| Adjuvant chemotherapy | 230 | 75.5 (70.1–81.4) | 0.02 | 69.8 (64.1–76.0) | 0.01 |
| No adjuvant chemotherapy | 245 | 68.4 (62.7–74.6) | 58.7 (52.8–65.3) | ||
|
| |||||
| High-frequency instability | 95 | ||||
| Adjuvant chemotherapy | 53 | 70.7 (59.2–84.5) | 0.07 | 69.3 (57.8–83.1) | 0.11 |
| No adjuvant chemotherapy | 42 | 88.0 (78.7–98.4) | 82.9 (72.1–95.3) | ||
*
P values are for the comparison between the rate in the given subgroup and that in the subgroup below it. CI denotes confidence interval.