Table 2.
Multivariable Cox regression for analyzing the prognosis factors for primary NPC with bone metastases.
| Subject characteristics | No. of NPC patients with bone metastases | Survival, median (IQR), mo | HR (95% CI) | P | |
|---|---|---|---|---|---|
| Overall | Dead (N, %) | ||||
| Age | |||||
| 0-24 | 11 | 6 (54.5) | 24 (7.903-40.097) | 1 (reference) | 1.0 |
| 25-49 | 77 | 47 (61.0) | 18 (14.907-21.093) | 1.298 (0.501-3.361) | 0.591 |
| 50-74 | 129 | 90 (69.8) | 13 (9.617-16.383) | 2.095 (0.805-5.448) | 0.129 |
| 75+ | 18 | 15 (83.3) | 7 (3.425-10.575) | 3.896 (1.291-11.754) | 0.016 |
| Gender | |||||
| Female | 46 | 30 (65.2) | 19 (10.596-27.404) | 1 (reference) | 1.0 |
| Male | 189 | 128 (67.7) | 13 (10.739-15.261) | 1.386 (0.885-2.171) | 0.153 |
| Race | |||||
| White | 96 | 64 (66.7) | 13 (7.163-18.837) | 1 (reference) | 1.0 |
| Black | 32 | 22 (68.8) | 13 (9.317-16.683) | 1.260 (0.723-2.195) | 0.415 |
| Others | 107 | 72 (67.3) | 15 (11.383-18.617) | 1.177 (0.805-1.723) | 0.400 |
| Marital status | |||||
| Married | 125 | 85 (68.0) | 14 (9.798-18.202) | 1 (reference) | 1.0 |
| Unmarried | 96 | 62 (64.6) | 16 (12.550-19.450) | 0.924 (0.644-1.326) | 0.668 |
| Unknown | 14 | 11 (78.6) | NA | NA | NA |
| Insurance status | |||||
| Insured | 125 | 78 (62.4) | 17 (13.007-20.993) | 1 (reference) | 1.0 |
| Uninsured | 94 | 67 (71.3) | 13 (9.003-16.997) | 1.338 (0.934-1.915) | 0.112 |
| Unknown | 16 | 13 (81.3) | NA | NA | NA |
| T stage | |||||
| T0 | 3 | 3 (100) | 12 (0.000-24.803) | 1 (reference) | 1.0 |
| T1 | 38 | 27 (71.1) | 16 (11.842-20.158) | 0.475 (0.130-1.727) | 0.258 |
| T2 | 22 | 14 (63.6) | 20 (9.457-30.543) | 0.329 (0.084-1.286) | 0.110 |
| T3 | 36 | 28 (77.8) | 15 (10.623-19.377) | 0.567 (0.154-2.085) | 0.392 |
| T4 | 69 | 55 (79.7) | 8 (5.829-10.171) | 0.699 (0.194-2.518) | 0.584 |
| Unknown | 66 | 30 (45.5) | NA | NA | NA |
| N stage | |||||
| N0 | 28 | 22 (78.6) | 12 (0.332-23.668) | 1 (reference) | 1.0 |
| N1 | 50 | 39 (78.0) | 13 (9.850-16.150) | 1.093 (0.603-1.980) | 0.769 |
| N2 | 57 | 42 (73.7) | 17 (13.379-20.621) | 0.919 (0.543-1.555) | 0.754 |
| N3 | 50 | 39 (78.0) | 13 (6.447-19.553) | 1.208 (0.669-2.179) | 0.531 |
| Unknown | 50 | 16 (32.0) | NA | NA | NA |
| Liver Met | |||||
| None | 152 | 91 (59.9) | 15 (12.02-17.980) | 1 (reference) | 1.0 |
| Yes | 79 | 64 (81.0) | 13 (9.811-16.189) | 1.375 (0.947-1.995) | 0.094 |
| Unknown | 4 | 3 (75.0) | NA | NA | NA |
| Brain Met | |||||
| None | 209 | 138 (66.0) | 15 (12.429-17.571) | 1 (reference) | 1.0 |
| Yes | 20 | 15 (75.0) | 5 (0.772-9.228) | 1.399 (0.771-2.540) | 0.270 |
| Unknown | 6 | 5 (83.3) | NA | NA | NA |
| Lung Met | |||||
| None | 171 | 110 (64.3) | 15 (12.048-17.952) | 1 (reference) | 1.0 |
| Yes | 59 | 45 (76.3) | 13 (6.425-19.575) | 1.361 (0.920-2.014) | 0.123 |
| Unknown | 5 | 3 (60.0) | NA | NA | NA |
| Sequence number | |||||
| One primary only | 212 | 138 (65.1) | 15 (12.305-17.695) | 1 (reference) | 1.0 |
| Others | 23 | 20 (87.0) | 7 (0.000-15.307) | 1.868 (1.061-3.287) | 0.030 |
All factors with unknown data were removed from the Cox and Kaplan–Meier model. NPC: nasopharyngeal carcinoma; IQR: interquartile range; mo: months; Met: metastases; Surg: surgical treatments; NA: not available.