Table 1.
Characteristics of study participants, according to NPC status
| Prospective study of high-risk, NPC multiplex families | Case-control study of prevalent NPC | |||
|---|---|---|---|---|
| Incident NPC (N=21) | Disease-free controls (N=50) | Early-stage NPC (N=30) | Controls (N=50) | |
| Age (years) | ||||
| 21–34 | 4 (19.1) | 12 (24.0) | 7 (23.3) | 5 (10.0) |
| 35–39 | 5 (23.8) | 9 (18.0) | 5 (16.7) | 10 (20.0) |
| 40–54 | 9 (42.9) | 16 (32.0) | 11 (36.7) | 23 (46.0) |
| 55–74 | 3 (14.3) | 13 (26.0) | 7 (23.3) | 12 (24.0) |
| Sex | ||||
| Female | 5 (23.8) | 12 (24.0) | 8 (26.7) | 17 (34.0) |
| Male | 16 (76.2) | 38 (76.0) | 22 (73.3) | 33 (66.0) |
| EBNA1 IgA positivea | 17 (85%)b | 24 (48%) | 30 (100%) | 25 (50%) |
a
Seropositivity for EBNA1 IgA calculated as previously described. (11)
b
Seropositivity for EBNA1 IgA calculated out of 20 incident NPC cases with available data