Table 1.
Demographic and Clinical Characteristics of Patients With Stage III Colon Cancer by Different Risk Groups
| Characteristics | High Risk (T4 and/or N2) | Low Risk (T1-3/N1) |
|---|---|---|
| N (%) | N (%) | |
| All | 168 | 239 |
| Age at diagnosis | ||
| <50 | 31 (18.5) | 48 (20.1) |
| 50-59 | 37 (22.0) | 60 (25.1) |
| 60-69 | 56 (33.3) | 75 (31.4) |
| ≥70 | 44 (26.2) | 56 (23.4) |
| Sex | ||
| Male | 92 (54.8) | 126 (52.7) |
| Female | 76 (45.2) | 113 (47.3) |
| Race/Ethnicity | ||
| Non-Hispanic white | 113 (67.3) | 161 (67.4) |
| Non-Hispanic black | 31 (18.5) | 44 (18.4) |
| Hispanics | 21 (12.5) | 29 (12.1) |
| Other | 3 (1.8) | 5 (2.1) |
| Insurance coverage | ||
| Private | 94 (56.0) | 130 (54.4) |
| Medicare/Other public | 48 (28.6) | 71 (29.7) |
| Medicaid | 15 (8.9) | 21 (8.8) |
| Not insured | 9 (5.4) | 16 (6.7) |
| Unknown | 2 (1.2) | 1 (0.4) |
| Census tract residence | ||
| 100% Urban | 101 (60.1) | 126 (52.7) |
| 100% Rural | 10 (6.0) | 16 (6.7) |
| Mixed | 55 (32.7) | 95 (39.8) |
| Unknown | 2 (1.2) | 2 (0.8) |
| Census tract poverty | ||
| <20% | 120 (71.4) | 184 (77.0) |
| ≥20% | 45 (26.8) | 53 (22.2) |
| Unknown | 3 (1.8) | 2 (0.8) |
| Census tract education | ||
| <25% (high) | 131 (78.0) | 186 (77.8) |
| ≥25% (low) | 35 (20.8) | 51 (21.3) |
| Unknown | 2 (1.2) | 2 (0.8) |
| Census tract marital status | ||
| ≤50% married | 81 (48.2) | 104 (43.5) |
| >50% married | 85 (50.6) | 133 (55.7) |
| Unknown | 2 (1.2) | 2 (0.8) |
| State of residence | ||
| AK | 2 (1.2) | 1 (0.4) |
| CO | 21 (12.5) | 42 (17.6) |
| FL | 48 (28.6) | 54 (22.6) |
| ID | 7 (4.2) | 15 (6.3) |
| LA | 45 (26.8) | 64 (26.8) |
| NC | 38 (22.6) | 58 (24.3) |
| NH | 6 (3.6) | 4 (1.7) |
| RI | 1 (0.6) | 1 (0.4) |
| Tumor size (cm) | ||
| ≤4 | 69 (41.1) | 130 (54.4) |
| >4 | 96 (57.1) | 97 (40.6) |
| Unknown | 3 (1.8) | 12 (5.0) |
| Lymph nodes examined | ||
| <12 | 13 (7.7) | 34 (14.2) |
| ≥12 | 155 (92.3) | 205 (85.8) |
| Tumor grade | ||
| Well/moderately differentiated | 109 (64.9) | 194 (81.2) |
| Poor/Undifferentiated | 58 (34.5) | 39 (16.3) |
| Unknown | 1 (0.6) | 6 (2.5) |
| Charlson Comorbidity Index | ||
| 0 | 113 (67.3) | 176 (73.6) |
| ≥1 | 55 (32.7) | 63 (26.4) |
| Anatomic subsite | ||
| Proximal colon (C18.0, C18.2-C18.5) | 104 (61.9) | 141 (59.0) |
| Distal colon (C18.6-C18.7) | 63 (37.5) | 92 (38.5) |
| Other (C18.8-C18.9) | 1 (0.6) | 6 (2.5) |
| Colon cancer classification | ||
| Only with colon cancer | 138 (82.1) | 197 (82.4) |
| Multiple cancers, first primary colon | 12 (7.1) | 16 (6.7) |
| Multiple cancers, nonfirst colon | 18 (10.7) | 26 (10.9) |
| Number of positive lymph nodes | 6.4 ± 4.5 | 2.0 ± 1.7 |
| Delayed chemotherapy | ||
| Yes (>8 weeks after surgery) | 36 (21.4%) | 56 (23.4%) |
| No (≤8 weeks after surgery) | 132 (78.6%) | 183 (76.6%) |
| Vital status | ||
| Alive | 135 (80.4) | 210 (87.9) |
| Death from colon cancer | 21 (12.5) | 15 (6.3) |
| Death from other causes | 4 (2.4) | 8 (3.3) |
| Death reasons unknown | 8 (4.8) | 6 (2.5) |
| Follow up time among alive patients (mean± standard deviation) | 34.6± 21.9 | 35.0± 22.8 |
| Median (interquartile range) | 40.3 (10.5-54.8) | 43.9 (10.6-57.1) |