Table 1.
Patient characteristics in the study
| Variable | Total | Low LND | High LND | P-value |
|---|---|---|---|---|
| Patients, n | 1,924 | 1,641 | 283 | |
| Age (years), median (25th–75th percentile) | 3 (2–5) | 3 (2–5) | 4 (3–6) | <0.001 |
| Sex, n (%) | 0.529 | |||
| Male | 917 (47.7) | 787 (48.0) | 130 (45.9) | |
| Female | 1,007 (52.3) | 854 (52.0) | 153 (54.0) | |
| Race, n (%) | 0.196 | |||
| White | 1,468 (76.3) | 1,240 (75.6) | 228 (80.6) | |
| Black | 329 (17.1) | 287(17.5) | 42 (14.8) | |
| Other | 105 (5.5) | 94 (5.7) | 11 (3.9) | |
| LNs examined, median (25th–75th percentile) | 4 (2–7) | 4 (2–8) | 3 (2–5) | <0.001 |
| SEER stage, n (%) | <0.001 | |||
| Localized | 832 (43.2) | 832 (50.7) | 0 (0.0) | |
| Regional | 655 (34.0) | 506 (30.8) | 149 (52.7) | |
| Distant | 417 (21.7) | 283 (17.2) | 134 (47.3) | |
| Surgery, n (%) | 0.584 | |||
| Yes | 1,533 (79.7) | 1,308 (79.7) | 225 (79.5) | |
| No | 6 (0.3) | 6 (0.4) | 0 (0.0) | |
| Unknown | 385 (20.0) | 327 (19.9) | 58 (20.5) | |
| Tumor laterality, n (%) | 0.008 | |||
| Unilateral | 1,840 (95.6) | 1,561 (95.1) | 279 (98.6) | |
| Bilateral | 84 (4.4) | 80 (4.9) | 4 (1.4) | |
| Year of diagnosis, n (%) | 0.161 | |||
| 1988 | 24 (1.2) | 22 (1.3) | 2 (0.7) | |
| 1989–1997 | 359 (18.7) | 303 (18.5) | 56 (19.8) | |
| 1998–2000 | 166 (8.6) | 133 (8.1) | 33 (11.7) | |
| 2000–2014 | 1,375 (71.5) | 1,183 (72.1) | 192 (67.8) |
Abbreviations: LNs, lymph nodes; LND, lymph node density; SEER, Surveillance, Epidemiology, and End Result.