Table 1

Demographic and disease characteristics of participating and nonparticipating NPC cases and controls

Controls (n = 142)Participating cases (n = 83)Nonparticipating cases (n = 114)
No.%No.%No.%
Age (yr)
 18–3916(11.3)15(18.1)15(13.1)
 40–4924(16.9)24(28.9)18(15.8)
 50–5936(25.3)19(22.9)33(19.3)
 60–6945(31.7)16(19.3)44(38.6)
 70–7421(14.8)9(10.8)15(13.1)
Sex
 Male94(66.2)57(68.7)76(66.7)
 Female48(33.8)26(36.3)38(33.3)
Race
 Caucasian133(93.7)57(68.7)79(69.7)
 African-American8(5.6)7(8.4)16(14.0)
 Asian017(20.5)11(9.6)
 Native American/Eskimo1(0.7)2(2.4)5(4.4)
 Other/unknown002(2.4)
Education completed
 Less than high school15(10.6)14(16.9)NAa
 High school38(26.8)30(36.1)NA
 More than high school89(62.7)39(47.0)NA
Histologyb
 Epithelial, NOS11(13.2)10(8.8)
 Undifferentiated and nonkeratinizing24(28.9)34(29.8)
 Squamous48(57.8)70(61.4)
Stage
 Local13(15.3)28(13.7)
 Regional52(61.2)113(55.1)
 Distant15(17.6)54(26.3)
 Unknown5(5.9)10(4.9)
  • a NA, not available.

  • b International Classification of Disease-Oncology classifications: epithelial, NOS, 801x–804x; undifferentiated, 8020, 8021, and 8082; nonkeratinizing, 8072 and 8073; squamous, 805x–808x, except 8072 and 8073.