Table 1.
Comparison of demographic and therapeutic characteristics of stage IIB/C and stage IIIA
| Before matching | After matching | |||||
|---|---|---|---|---|---|---|
| Variable | Stage IIB/C | Stage IIIA | P | Stage IIB/C | Stage IIIA | P |
| No. of patients (%) | 18,609 (53.2) | 16,390 (46.8) | 11,409 (50.0) | 11,409 (50.0) | ||
| Age | <.0001 | 0.94 | ||||
| 18–49 | 1,678 (9.0) | 1424 (8.7) | 935 (8.2) | 920 (8.1) | ||
| 50–64 | 4,628 (24.9) | 5284 (32.2) | 2,979 (26.1) | 3,016 (26.4) | ||
| 65–74 | 4,368 (23.5) | 4419 (27.0) | 2,957 (25.9) | 2,956 (25.9) | ||
| 75 and more | 7,935 (42.6) | 5263 (32.1) | 4,538 (39.8) | 4,517 (39.6) | ||
| Distance from cancer reporting facility | 0.06 | 0.58 | ||||
| <50 miles | 16,909 (92.9) | 15,015 (93.4) | 10,630 (93.2) | 10,651 (93.4) | ||
| ≥50 miles | 1,303 (7.2) | 1,066 (6.6) | 779 (6.8) | 758 (6.6) | ||
| Race/Ethnicity | <.0001 | 0.93 | ||||
| White | 15,964 (86.5) | 13,450 (82.8) | 9,785 (85.8) | 9,770 (85.6) | ||
| Black | 1,965 (10.6) | 2,197 (13.5) | 1,283 (11.3) | 1,308 (11.5) | ||
| American Indian, Aleutian, or Eskimo | 53 (0.3) | 36 (0.2) | 27 (0.2) | 31 (0.3) | ||
| Asian or Pacific Islander | 390 (2.1) | 456 (2.8) | 261 (2.3) | 251 (2.2) | ||
| Other | 89 (0.5) | 100 (0.6) | 53 (0.5) | 49 (0.4) | ||
| Facility Type | 0.02 | 0.90 | ||||
| Community cancer program | 2,715 (14.6) | 2,239 (13.7) | 1,565 (13.7) | 1,588 (13.9) | ||
| Comprehensive community cancer center | 11,044 (59.4) | 9,700 (59.2) | 6,815 (59.7) | 6,804 (59.6) | ||
| Academic research program | 4,825 (25.9) | 4,432 (27.0) | 3,029 (26.6) | 3,017 (26.4) | ||
| Other specified types of cancer program | 25 (0.1) | 19 (0.1) | ||||
| Facility Location | <.0001 | 0.99 | ||||
| New England | 1,335 (7.2) | 886 (5.4) | 678 (5.9) | 692 (6.1) | ||
| Mid Atlantic | 2,971 (16.0) | 2,402 (14.7) | 1,814 (15.9) | 1,809 (15.9) | ||
| South Atlantic | 3,835 (20.6) | 3,715 (22.7) | 2,352 (20.6) | 2,391 (21.0) | ||
| East North Central | 3,580 (19.2) | 3,127 (19.1) | 2,174 (19.1) | 2,201 (19.3) | ||
| East South Central | 1,162 (6.2) | 1,186 (7.2) | 788 (6.9) | 786 (6.9) | ||
| West North Central | 1,555 (8.4) | 1,333 (8.1) | 1,035 (9.1) | 1,002 (8.8) | ||
| West South Central | 1,487 (8.0) | 1,391 (8.5) | 942 (8.3) | 938 (8.2) | ||
| Mountain | 779 (4.2) | 678 (4.1) | 440 (3.9) | 438 (3.8) | ||
| Pacific | 1,905 (10.2) | 1,672 (10.2) | 1,186 (10.4) | 1,152 (10.1) | ||
| Urban/Rural Location | 0.05 | 0.96 | ||||
| Metro ≥1 million | 9,488 (53.0) | 8,380 (53.1) | 6,039 (52.9) | 6,028 (52.8) | ||
| Metro 250 k to 1 million | 3,863 (21.6) | 3,556 (22.5) | 2,539 (22.3) | 2,554 (22.4) | ||
| Urban <250 k | 1,766 (9.9) | 1,516 (9.6) | 1,104 (9.7) | 1,112 (9.8) | ||
| Urban ≥ 20 k adjacent metro | 731 (4.1) | 657 (4.2) | 460 (4.0) | 476 (4.2) | ||
| Urban ≥ 20 k not adjacent metro | 262 (1.5) | 221 (1.4) | 182 (1.6) | 175 (1.5) | ||
| Urban <20 k adjacent metro | 957 (5.4) | 751 (4.8) | 577 (5.1) | 572 (5.0) | ||
| Urban <20 k not adjacent metro | 454 (2.5) | 387 (2.5) | 286 (2.5) | 258 (2.3) | ||
| Rural <2500 adjacent metro | 164 (0.9) | 169 (1.1) | 108 (1.0) | 109 (1.0) | ||
| Rural <2500 not adjacent metro | 212 (1.2) | 154 (1.0) | 114 (1.0) | 125 (1.1) | ||
| Comorbidities | <.0001 | 0.61 | ||||
| 0 | 12,872 (69.2) | 11,665 (71.2) | 7,905 (69.3) | 7,962 (69.8) | ||
| 1 | 4,185 (22.5) | 3,537 (21.6) | 2,576 (22.6) | 2,513 (22.0) | ||
| 2 | 1,552 (8.3) | 1,188 (7.3) | 928 (8.1) | 934 (8.2) | ||
| Primary Site | <.0001 | 0.99 | ||||
| Cecum | 4,917 (26.4) | 3,941 (24.1) | 3,077 (27.0) | 3,077 (27.0) | ||
| Ascending Colon | 2,876 (15.5) | 3,140 (19.2) | 1,969 (17.3) | 1,992 (17.5) | ||
| Hepatic Flexure | 748 (4.0) | 608 (3.7) | 473 (4.2) | 461 (4.0) | ||
| Transverse Colon | 2,061 (11.1) | 1,154 (7.0) | 1,031 (9.0) | 991 (8.7) | ||
| Splenic Flexure | 786 (4.2) | 366 (2.2) | 312 (2.7) | 327 (2.9) | ||
| Descending Colon | 1,161 (6.2) | 960 (5.9) | 705 (6.2) | 706 (6.2) | ||
| Sigmoid Colon | 5,324 (28.6) | 5,756 (35.1) | 3,524 (30.9) | 3,535 (31.0) | ||
| Overlapping Lesions | 369 (2.0) | 140 (0.9) | 120 (1.1) | 121 (1.1) | ||
| Not Otherwise Specified | 367 (2.0) | 325 (2.0) | 198 (1.7) | 199 (1.7) | ||
| Grade | <.0001 | 0.87 | ||||
| Well differentiated | 1,506 (8.4) | 1,779 (11.4) | 1,087 (9.5) | 1,084 (9.5) | ||
| Moderately differentiated | 11,868 (66.0) | 11,226 (71.9) | 8,007 (70.2) | 8,049 (70.6) | ||
| Poorly differentiated | 4,004 (22.3) | 2,381 (15.3) | 2,084 (18.3) | 2,059 (18.1) | ||
| Undifferentiated, anaplastic | 611 (3.4) | 230 (1.5) | 231 (2.0) | 217 (1.9) | ||
| Surgical Margins | <.0001 | 0.87 | ||||
| No residual tumor | 14992 (82.6) | 16,012 (98.8) | 11,243 (98.6) | 11,246 (98.6) | ||
| With Residual tumor | 3156 (17.4) | 190 (1.2) | 166 (1.5) | 163 (1.4) | ||
| Regional Lymph Nodes Examined | <.0001 | <.0001 | ||||
| 0–11 | 4,399 (23.8) | 4,867 (29.9) | 2,422 (21.3) | 3,298 (29.0) | ||
| 12–90 | 14,101 (76.2) | 11,434 (70.1) | 8,944 (78.7) | 8,078 (71.0) | ||
| Chemotherapy | <.0001 | <.0001 | ||||
| None | 10,423 (58.7) | 4,807 (30.5) | 6,362 (58.4) | 3,659 (33.3) | ||
| Yes | 7,335 (41.3) | 10,975 (69.5) | 4,525 (41.6) | 7,327 (66.7) | ||