Table 1.
Characteristics of Cohort by Receipt of Chemotherapy
| Characteristic | Chemotherapy | No Chemotherapy | |||
|---|---|---|---|---|---|
| No. | Col % | No. | Col % | P | |
| All cancers | 18,486 | — | 18,486 | — | |
| Site | |||||
| Bladder | 206 | 1 | 206 | 1 | |
| Breast | 1,127 | 6 | 1,127 | 6 | |
| Colorectal | 3,625 | 20 | 3,625 | 20 | |
| Esophageal | 278 | 2 | 278 | 2 | |
| Non–small-cell lung | 4,705 | 25 | 4,705 | 25 | |
| Ovary | 630 | 3 | 630 | 3 | |
| Pancreas | 2,813 | 15 | 2,813 | 15 | |
| Prostate | 1,321 | 7 | 1,321 | 7 | |
| Small-cell lung | 2,996 | 16 | 2,996 | 16 | |
| Stomach | 785 | 4 | 785 | 4 | |
| Age at diagnosis, years | |||||
| 66-69 | 3,590 | 19 | 3,071 | 17 | < .001 |
| 70-74 | 4,934 | 27 | 4,418 | 24 | |
| 75-79 | 5,076 | 27 | 4,777 | 26 | |
| 80-84 | 3,384 | 18 | 4,029 | 22 | |
| ≥ 85 | 1,502 | 8 | 2,191 | 12 | |
| Sex | |||||
| Male | 9,641 | 52 | 9,641 | 52 | |
| Female | 8,845 | 48 | 8,845 | 48 | |
| Race | |||||
| White | 16,105 | 87 | 16,105 | 87 | |
| Black | 1,427 | 8 | 1,427 | 8 | |
| Other | 954 | 5 | 954 | 5 | |
| Census tract median income, quartile | |||||
| 1st | 4,094 | 22 | 4,899 | 27 | < .001 |
| 2nd | 4,558 | 25 | 4,799 | 26 | |
| 3rd | 4,742 | 26 | 4,537 | 25 | |
| 4th | 5,059 | 27 | 4,198 | 23 | |
| Unknown | 33 | < 1 | 53 | < 1 | |
| Urban-rural residence | |||||
| Metropolitan | 15,464 | 84 | 15,057 | 81 | < .001 |
| Nonmetropolitan | 3,022 | 16 | 3,429 | 19 | |
| Region | |||||
| Northeast | 4,095 | 22 | 4,095 | 22 | |
| South | 4,880 | 26 | 4,880 | 26 | |
| Midwest | 2,210 | 12 | 2,210 | 12 | |
| West | 7,301 | 39 | 7,301 | 39 | |
| Married | |||||
| Yes | 10,310 | 56 | 8,341 | 45 | < .001 |
| No | 7,659 | 41 | 9,518 | 51 | |
| Unknown | 517 | 3 | 627 | 3 | |
| Charlson comorbidity score | |||||
| 0 | 10,745 | 58 | 10,745 | 58 | |
| 1 | 4,537 | 25 | 4,537 | 25 | |
| 2+ | 3,204 | 17 | 3,204 | 17 | |
| Radiation therapy | |||||
| Yes | 6,562 | 35 | 4,369 | 24 | < .001 |
| No | 11,924 | 65 | 14,117 | 76 | |
NOTE. Column percentages show distribution of characteristics within each group (chemotherapy recipients and nonrecipients). Chemotherapy recipients and nonrecipients were pair-matched by age, sex, race, SEER region, comorbidity score, and survival duration.