Table 1

Characteristics of the study population (n = 3580)

Cases (n = 1608)Controls (n = 1972)Pa
Tumor site
 Proximal794 (49%)
 Distal775 (48%)
 Unknown site39 (3%)
Age at diagnosis or selection (range, 30–79)
 Yearsb64.4 +/− 9.864.5 +/− 10.10.77
Sex
 Men900 (56%)1042 (53%)
 Women708 (44%)930 (47%)0.06
Recent hormone-replacement therapy use, postmenopausal womenc
 No470 (77%)551 (69%)
 Yes144 (23%)243 (31%)<0.01
Kilocaloriesb
 Men2773 +/− 12172637 +/− 11600.01
 Women2048 +/− 8761972 +/− 8310.07
Folate (mcg/day)d
 Men387 (215)393 (214)0.80
 Women320 (177)321 (174)0.68
Vitamin B12 (mcg/day)d
 Men6.5 (4.9)6.3 (4.7)0.18
 Women4.5 (3.4)4.5 (3.4)0.61
Long-term alcohol intake (gm/day)d
 Men14.7 (27.0)12.0 (24.8)0.08
 Women3.7 (9.2)3.7 (9.0)0.43
MTHFR 677 and 1298 genotypese
 677 CC (wt) and 1298 AA (wt)223 (14%)247 (13%)
 677 CT (het) and 1298 AA (wt)384 (24%)455 (23%)
 677 TT (var) and 1298 AA (wt)150 (9%)227 (12%)
 677 CC (wt) and 1298 AC (het)358 (22%)424 (21%)
 677 CT (het) and 1298 AC (het)340 (21%)403 (20%)
 677 TT (var) and 1298 AC (het)
 677 CC (wt) and 1298 CC (var)153 (10%)216 (11%)
 677 CT (het) and 1298 CC (var)
 677 TT (var) and 1298 CC (var)0.17
  • a Based on χ2 or t test.

  • b Mean +/− SD.

  • c Hormone replacement therapy within 2 years of diagnosis/selection.

  • d Median (interquartile range) for dietary intake. Long-term alcohol intake based on consumption of wine, beer, and liquor for drinkers reported 10 and 20 years ago, averaged.

  • e Some genotypes of MTHFR 677 and 1298 were not observed, presumably due to complete linkage disequilibrium.