Table 2.
Baseline of clinical features and distribution of risk groups. According to different prognostic models for all patients and early-stage patients in the validation cohort.
| Characteristic | All | Early stage |
|---|---|---|
| No. (%) | No. (%) | |
| Total number | 1582 (100) | 1367 (86.4) |
| Sex | ||
| Male | 1110 (70.2) | 956 (69.9) |
| Female | 472 (29.8) | 411 (30.1) |
| Age (years) | ||
| ≤60 | 1336 (84.5) | 1149 (84.1) |
| >60 | 246 (15.5) | 218 (15.9) |
| Primary site | ||
| UADT (nasal) | 1464 (92.5) | 1325 (96.9) |
| Extra-UADT (nonnasal) | 118 (7.5) | 42 (3.1) |
| Regional lymph nodes | ||
| Yes | 604 (38.2) | 477 (34.9) |
| No | 978 (61.8) | 890 (65.1) |
| Distant lymph nodes | ||
| Yes | 91 (5.8) | NA |
| No | 1491 (94.2) | 1367 (100) |
| PTI | ||
| Yes | 873 (55.2) | 732 (53.5) |
| No | 709 (44.8) | 635 (46.5) |
| B symptoms | ||
| Yes | 628 (39.7) | 516 (37.7) |
| No | 954 (60.3) | 851 (62.3) |
| Elevated LDH | ||
| Yes | 418 (26.4) | 308 (22.5) |
| No | 1164 (73.6) | 1059 (77.5) |
| ECOG score | ||
| 0–1 | 1479 (93.5) | 1314 (96.1) |
| ≥2 | 103 (6.5) | 53 (3.9) |
| Distant extranodal organs | ||
| 0 | 1417 (89.6) | 1367 (100) |
| 1 | 111 (7.0) | NA |
| ≥2 | 54 (3.4) | NA |
| Ann Arbor stage | ||
| I | 890 (56.3) | 890 (56.3) |
| II | 477 (30.2) | 477 (30.2) |
| III | 50 (3.2) | NA |
| IV | 165 (10.4) | NA |
| IPI | ||
| Low (0–1) | 1354 (85.6) | 1289 (94.3) |
| Intermediate low (2) | 145 (9.2) | 69 (5.0) |
| Intermediate high (3) | 65 (4.1) | 9 (0.7) |
| High (≥4) | 18 (1.1) | 0 (0) |
| KPI | ||
| Group 1 (0) | 490 (31.0) | 490 (35.8) |
| Group 2 (1) | 563 (35.6) | 532 (38.9) |
| Group 3 (2) | 330 (20.8) | 266 (19.5) |
| Group 4 (≥3) | 199 (12.6) | 79 (5.8) |
| PINK | ||
| Low risk (0) | 1088 (68.8) | 1088 (79.6) |
| Intermediate risk (1) | 334 (21.1) | 260 (19.0) |
| High risk (≥2) | 160 (10.1) | 19 (1.4) |
| NRI | ||
| Low risk (0) | 352 (22.3) | 352 (25.7) |
| Intermediate low risk (1) | 447 (28.3) | 447 (32.7) |
| Intermediate high risk (2) | 423 (26.7) | 395 (28.9) |
| High risk (3)a | 223 (14.1) | 173 (12.7) |
| Very high risk (≥4) | 137 (8.7) | NA |
UADT upper aerodigestive tract, PTI primary tumor invasion, LDH lactate dehydrogenase, ECOG Eastern Cooperative Oncology Group, NA not available, IPI International Prognostic Index, KPI Korean Prognostic Index, PINK prognostic index of natural killer lymphoma, NRI Nomogram-revised risk index.
aHigh-risk group was defined as NRI ≥ 3 for early-stage patients.