Table 1. Characteristics of study patients.
| Characteristic | n = 260 |
|---|---|
| No. of patients (%) | |
| Mean age in years (range) | 53 (16–91) |
| Male/female | 183 (70.4)/77 (29.6) |
| ECOG performance status | |
| 0 | 16 (6.2) |
| 1 | 244 (93.8) |
| T-classification | |
| T1 | 77 (29.6) |
| T2 | 28 (10.8) |
| T3 | 115 (44.2) |
| T4 | 40 (15.4) |
| N-classification | |
| N0 | 30 (11.5) |
| N1 | 74 (28.5) |
| N2 | 121 (46.5) |
| N3a | 4 (1.5) |
| N3b | 31 (11.9) |
| Overall stage | |
| I | 17 (6.5) |
| II | 38 (14.6) |
| III | 135 (51.9) |
| IVA | 35 (13.5) |
| IVB | 35 (13.5) |
| Laterality of primary tumor | |
| Midline | 142 (54.6) |
| Left | 57 (21.9) |
| Right | 61 (23.5) |
| Retropharyngeal node present | 200 (76.9) |
| Laterality of retropharyngeal node (n = 200) | |
| Ipsilateral | 88 (44.0) |
| Contralateral | 3 (1.5) |
| Bilateral | 109 (54.5) |
| Median baseline plasma EBV DNA in copies/ml (range) | 934 (10–1575000) |
| Stage I (n = 17) | 13 (10–210) |
| Stage II (n = 38) | 746 (10–21250) |
| Stage III (n = 135) | 847 (11–175000) |
| Stage IVA (n = 35) | 1400 (10–90500) |
| Stage IVB (n = 35) | 7625 (12–1575000) |
| Radical IMRT only | 46 (17.7) |
| Concurrent chemoradiation | 26 (10.0) |
| Induction chemotherapy then concurrent chemoradiation | 89 (34.2) |
| Concurrent chemoradiation then adjuvant chemotherapy | 99 (38.1) |
DNA: deoxyribonucleic acid, EBV: Epstein-Barr virus, ECOG: Eastern Cooperative Oncology Group, IMRT: intensity-modulated radiation therapy.