Table 1. Descriptive characteristics of 3957 patients of study population within the Surveillance, Epidemiology, and End Results (SEER) Medicare-linked database and 272 propensity score-matched patients.
| Characteristics | Entire cohort (n = 3957) | Propensity score-matched cohort (n = 272) | ||||
|---|---|---|---|---|---|---|
| RA, n(%) | AA, n(%) | P Value | RA, n(%) | AA, n(%) | P Value | |
| n = 3821 (96.56) | N = 136 (3.44) | 136 (50) | 136 (50) | |||
| Age | 0.311 | 0.754 | ||||
| <50 | 872(22.82) | 26(19.12) | 24(17.65) | 26(19.12) | ||
| ≥50 | 2949(77.18) | 110(80.88) | 112(82.35) | 110(80.88) | ||
| Gender | 0.935 | 0.801 | ||||
| Female | 1446(37.84) | 51(37.50) | 49(36.03) | 51(37.5) | ||
| Male | 2375(62.16) | 85(62.50) | 87(63.97) | 85(62.5) | ||
| Race | 0.097 | 0.826 | ||||
| White | 3092(80.92) | 102(75.00) | 103(75.74) | 102(75) | ||
| Black | 355(9.29) | 20(14.71) | 17(12.5) | 20(14.71) | ||
| Other | 374(9.79) | 14(10.29) | 16(11.76) | 14(10.29) | ||
| Marital status | 0.057 | 0.536 | ||||
| Married | 2421(63.36) | 74(54.41) | 75(55.15) | 74(54.41) | ||
| Single | 586(15.34) | 22(16.18) | 16(11.76) | 22(16.18) | ||
| Divorce | 814(21.30) | 40(29.41) | 45(33.09) | 40(29.41) | ||
| Histology | 0.000 | 0.710 | ||||
| Adenocarcinoma | 3475(90.94) | 108(79.41) | 110(80.88) | 108(79.41) | ||
| Mucinous | 303(7.93) | 24(17.65) | 24(17.65) | 24(17.65) | ||
| SRCC | 43(1.13) | 4(2.94) | 2(1.47) | 4(2.94) | ||
| Grade | 0.001 | 0.726 | ||||
| Well | 271(7.09) | 18(13.24) | 21(15.44) | 18(13.24) | ||
| Moderate | 2870(75.11) | 83(61.03) | 85(62.5) | 83(61.03) | ||
| Poor | 680(17.80) | 35(25.74) | 30(22.06) | 35(25.74) | ||
| No. of positive LNs | 0.884 | 0.474 | ||||
| 0 | 2324(60.82) | 85(62.50) | 22(16.18) | 22(16.18) | ||
| 1–3 | 907(23.74) | 32(23.53) | 58(42.65) | 61(44.85) | ||
| ≥4 | 590(15.44) | 19(13.97) | 56(41.18) | 53(38.97) | ||
| Size (cm) | 0.199 | 0.924 | ||||
| 2≤2 | 433(11.33) | 22(16.18) | 86(63.24) | 85(62.5) | ||
| 2–5 | 1887(49.38) | 61(44.85) | 37(27.21) | 32(23.53) | ||
| >5 | 1501(39.28) | 53(38.97) | 13(9.56) | 19(13.97) | ||
| Radiotherapy | 0.053 | 0.222 | ||||
| Yes | 905(23.68) | 42(30.88) | 33(24.26) | 42(30.88) | ||
| No | 2916(76.32) | 94(69.12) | 103(75.74) | 94(69.12) | ||
| Chemotherapy | 0.011 | 0.226 | ||||
| Yes | 853(22.32) | 43(31.62) | 34(25) | 43(31.62) | ||
| No | 2968(77.68) | 93(68.38) | 102(75) | 93(68.38) | ||
SRCC: Signet Ring Cell Carcinoma; No: Number; LN: Lymph Node; RA: Rectal Adenocarcinoma; AA: Anal Adenocarcinoma