Table 5

Pooled analysis of case–control studies on the GSTM1, GSTT1, GSTP1 (ILE105VAL), and CYP1A1 (ILE462VAL) genotypes and head and neck cancer

Principal investigatorFirst author (Refs.)CountryControl sourceSiteCases (n)Controls (n)GSTM1 (null), ORa (95% CI)GSTT1 (null), OR (95% CI)GSTP1 (any Val), OR (95% CI)CYP1A1 (any Val), OR (95% CI)
OralPharynxLarynx
BenhamouJourenkova (25 26 27)FranceHospitalXXX2501721.09 (0.74–1.60)1.38 (0.82–2.30)1.23 (0.83–1.82)
BhiseyBuch (13)IndiaHospital- healthyX300bcd678c,d1.73 (1.49–1.99)1.61 (1.11–2.33)1.06 (0.76–1.48)
CascorbiUnpublishedGermanyHospital- healthyXX505f223f2.01 (1.34–3.01)1.26 (0.65–2.43)1.02 (0.51–2.04)
CoutelleCoutelle (15)FranceAlcoholism clinicXX39c,d,e76c,d,e2.37 (1.05–5.36)
FoulkesHamel (20)CanadaMixedXXX196b,f199f1.09 (0.74–1.62)1.15 (0.67–1.98)
KatohKatoh (29 , 30)JapanHealthyX45911.59 (0.78–3.27)
LazarusPark (42 43 44)United StatesHospitalXX185f367f1.40 (0.96–2.03)0.87 (0.57–1.33)
ManniOude Ophuis (40)NetherlandsHospital- healthyXXX245b,f159f1.33 (0.77–2.29)0.56 (0.30–1.05)0.77 (0.52–1.14)0.63 (0.33–1.19)
RomkesUnpublishedUnited StatesHealthyHead and neck40f70f0.79 (0.36–1.73)0.84 (0.25–2.84)
StrangeDeakin (16)United KingdomHospitalX107f493f0.69 (0.45–1.05)1.38 (0.84–2.27)1.53 (0.94–2.48)2.11 (0.85–5.24)
StrangeMatthias (34 , 35)GermanyHospitalXXX422f238f1.31 (0.94–1.83)1.54 (0.91–2.63)1.56 (1.11–2.19)0.87 (0.55–1.38)
No. of studies (cases/controls) in data11 (2224/2517)8 (1929/1830)5 (1164/982)5 (1558/1467)
Summary ORa1.32 (1.07–1.62)1.25 (1.00–1.57)1.15 (0.86–1.53)0.98 (0.75–1.29)
Test for heterogeneity0.000.220.040.28
Publication bias (Egger’s test)0.150.140.750.79
Oral1.20 (0.89–1.63)1.34 (0.99–1.82)1.37 (0.88–2.14)0.97 (0.56–1.69)
Pharynx1.25 (0.98–1.61)1.11 (0.66–1.87)1.10 (0.58–2.05)0.77 (0.47–1.25)
Larynx1.53 (1.17–2.00)1.10 (0.81–1.49)1.08 (0.81–1.44)0.93 (0.64–1.34)
Never smokers1.58 (1.11–2.23)1.29 (0.83–1.99)1.38 (0.46–4.12)0.95 (0.62–1.45)
Ever smokers1.33 (1.01–1.74)1.23 (0.77–1.94)1.01 (0.76–1.33)0.87 (0.50–1.51)
Caucasians1.19 (0.93–1.51)1.17 (0.91–1.50)1.15 (0.86–1.54)0.95 (0.64–1.43)
SCC1.24 (0.99–1.54)1.17 (0.88–1.55)1.13 (0.83–1.54)
  • a OR, odds ratio (all ORs from the pooled analysis are adjusted for study center); CI, confidence interval; SCC, squamous cell carcinoma.

  • b Prevalent and incident cases.

  • c All ever tobacco smokers and/or chewers.

  • d All males.

  • e All drinkers.

  • f Number of cases and controls genotyped varied for each gene; thus, overall numbers are presented.