Table 1.
Demographics and Clinical Characteristics of Medicare Beneficiaries Undergoing Resection for Stages I to III Colon Cancer
| Characteristic | Patients (%) |
P | ||
|---|---|---|---|---|
| All (N = 53,801) | Right-Sided Cancer (n = 36,066) | Left-Sided Cancer (n = 17,735) | ||
| Demographic | ||||
| Age, years | < .001 | |||
| 65-69 | 12.5 | 11.1 | 15.4 | |
| 70-74 | 21.3 | 19.9 | 24.0 | |
| 75-79 | 25.2 | 25.0 | 25.5 | |
| 80-84 | 22.1 | 23.0 | 20.3 | |
| ≥ 85 | 19.0 | 21.1 | 14.8 | |
| Male sex | 41.4 | 38.3 | 47.8 | < .001 |
| Ethnicity | < .001 | |||
| White | 85.9 | 86.9 | 83.7 | |
| Black | 6.2 | 6.0 | 6.7 | |
| Asian or Pacific Islander | 4.2 | 3.5 | 5.8 | |
| Hispanic | 3.4 | 3.3 | 3.5 | |
| Other | 0.4 | 0.4 | 0.3 | |
| Marital status | < .001 | |||
| Married | 50.7 | 49.1 | 53.8 | |
| Widowed | 34.7 | 36.2 | 31.5 | |
| Single, separated, or divorced | 11.6 | 11.6 | 11.7 | |
| Unknown | 3.1 | 3.1 | 3.0 | |
| SEER registry* | < .001 | |||
| California | 28.8 | 28.8 | 28.8 | |
| Connecticut | 10.4 | 10.2 | 10.8 | |
| Detroit | 10.3 | 10.2 | 10.4 | |
| Hawaii | 1.8 | 1.5 | 2.4 | |
| Iowa | 13.0 | 13.2 | 12.5 | |
| New Mexico | 2.5 | 2.3 | 2.9 | |
| Seattle | 7.3 | 7.6 | 6.7 | |
| Utah | 3.1 | 3.0 | 3.1 | |
| Atlanta and rural Georgia | 3.9 | 3.9 | 3.9 | |
| Kentucky | 4.9 | 4.9 | 4.8 | |
| Louisiana | 4.1 | 3.9 | 4.6 | |
| New Jersey | 10.0 | 10.4 | 9.1 | |
| Residence location | .12 | |||
| Major metropolitan | 55.8 | 56.1 | 55.2 | |
| Metropolitan or urban | 34.0 | 33.7 | 34.6 | |
| Less urban or rural | 10.3 | 10.3 | 10.3 | |
| Median household income (census tract), $ in thousands† | < .001 | |||
| Mean | 45.2 | 45.6 | 44.3 | |
| SD | 22.1 | 22.3 | 21.8 | |
| Less than 12 years education (census tract), %† | < .001 | |||
| Mean | 18.9 | 18.6 | 19.6 | |
| SD | 12.5 | 12.3 | 12.8 | |
| Year of diagnosis by Medicare colonoscopy coverage, % | < .001 | |||
| 1992-1997 | 31.8 | 30.1 | 35.0 | |
| 1998-June 2001 | 24.7 | 24.9 | 24.1 | |
| July 2001-2005 | 43.6 | 44.9 | 40.9 | |
| AJCC stage | < .001 | |||
| I | 24.3 | 23.3 | 26.3 | |
| II | 43.8 | 44.3 | 42.8 | |
| III | 31.9 | 32.3 | 31.0 | |
| Poor prognostic feature | ||||
| Emergent admission | 17.5 | 17.7 | 17.3 | .29 |
| Intestinal obstruction on admission | 4.0 | 3.0 | 5.9 | < .001 |
| Intestinal perforation on admission | 1.6 | 1.3 | 2.3 | < .001 |
| T stage | < .001 | |||
| Tis, T0, T1, or T2 | 27.7 | 26.6 | 29.9 | |
| T3 | 60.1 | 60.9 | 58.4 | |
| T4 | 12.3 | 12.5 | 11.7 | |
| No. of nodes resected | < .001 | |||
| 0-11 | 55.7 | 49.6 | 68.2 | |
| ≥ 12 | 44.3 | 50.4 | 31.8 | |
| Tumor grade | < .001 | |||
| Well differentiated | 9.3 | 8.7 | 10.6 | |
| Moderately differentiated | 69.6 | 66.5 | 75.8 | |
| Poorly or undifferentiated | 21.1 | 24.9 | 13.6 | |
| Comorbidity and treatment measure | ||||
| HCC risk score† | < .001 | |||
| Mean | 2.11 | 2.13 | 2.06 | |
| SD | 1.38 | 1.36 | 1.41 | |
| Any hospitalization in the previous year | 26.6 | 27.8 | 24.2 | < .001 |
| Rehospitalization within 30 days of discharge | 11.1 | 11.1 | 11.2 | .93 |
| Any in-hospital surgical complication | 3.4 | 2.8 | 4.7 | < .001 |
| Oncologist visit within 30 days of surgery | 30.4 | 30.7 | 29.7 | .02 |
| Postoperative adjuvant chemotherapy | < .001 | |||
| None | 72.4 | 73.0 | 71.1 | |
| Incomplete: 1-4 months | 8.9 | 9.0 | 8.6 | |
| Complete: ≥ 5 months | 18.7 | 18.0 | 20.2 | |
Abbreviations: AJCC, American Joint Committee on Cancer; HCC, Hierarchical Condition Categories; SD, standard deviation; SEER, Surveillance, Epidemiology, and End Results.
*
Three SEER registries (ie, Kentucky, Louisiana, and New Jersey) were added in 2000.
†
N = 2,856 individuals with missing data not included in these means.