Table 1.

Characteristics of study participants, according to NPC status

Prospective study of high-risk, NPC multiplex familiesCase–control study of prevalent NPC
Incident NPC (N = 21)Disease-free controls (N = 50)Early-stage NPC (N = 30)Controls (N = 50)
Age (years)
 21–344 (19.1)12 (24.0)7 (23.3)5 (10.0)
 35–395 (23.8)9 (18.0)5 (16.7)10 (20.0)
 40–549 (42.9)16 (32.0)11 (36.7)23 (46.0)
 55–743 (14.3)13 (26.0)7 (23.3)12 (24.0)
Sex
 Female5 (23.8)12 (24.0)8 (26.7)17 (34.0)
 Male16 (76.2)38 (76.0)22 (73.3)33 (66.0)
EBNA1 IgA positivea17 (85%)b24 (48%)30 (100%)25 (50%)
  • aSeropositivity for EBNA1 IgA calculated as described previously (11).

  • bSeropositivity for EBNA1 IgA calculated out of 20 incident NPC cases with available data.