Flavonoids and the risk of oral and pharyngeal cancer: a case-control study from Italy.
The intake of flavonoids has been inversely related to the risk of various common neoplasms, but scanty data exist on oral and pharyngeal cancer. We used data from a case-control study conducted in Italy between 1992 and 2005 to examine the relationship between flavonoid intake and oral and pharyngeal cancer risk. The study included 805 cases with incident, histologically confirmed oral and pharyngeal cancer, and 2,081 hospital controls admitted for acute, nonneoplastic conditions. We have applied data on food and beverage content of six major classes of flavonoids, on dietary information collected through a validated food-frequency questionnaire. The odds ratios (OR) were calculated using multiple logistic regression models, conditioned on study center, sex, and age. After adjustment for education, tobacco, alcohol, body mass index, and non-alcohol energy intake, ORs for the highest versus the lowest quintile of intake were 0.51 [95% confidence intervals (95% CI), 0.37-0.71] for flavanones, 0.62 (CI, 0.43-0.89) for flavonols, and 0.56 (95% CI, 0.40-0.78) for total flavonoids. No significant association emerged for isoflavones (OR, 0.90), anthocyanidins (OR, 0.86), flavan-3-ols (OR, 0.84), and flavones (OR, 0.75). The ORs were consistent across strata of age, sex, education, body mass index, tobacco, and alcohol. After allowance for vegetable and fruit consumption, the inverse relations with total flavonoids and flavanones remained significant, whereas that with flavonols became nonsignificant. None of the associations were significant after further allowance for vitamin C, probably on account of the high collinearity between these compounds.
Istituto di Ricerche Farmacologiche Mario Negri, Via La Masa 19, 20156, Milan, Italy. mrossi@marionegri.it
Marta
M
Rossi
Werner
W
Garavello
Renato
R
Talamini
Eva
E
Negri
Cristina
C
Bosetti
Luigino
L
Dal Maso
Pagona
P
Lagiou
Alessandra
A
Tavani
Jerry
J
Polesel
Luigi
L
Barzan
Valerio
V
Ramazzotti
Silvia
S
Franceschi
Carlo
C
La Vecchia
D000328:Adult; D000368:Aged; D000428:Alcohol Drinking; D000872:Anthocyanins / Q000008:administration & dosage; D015992:Body Mass Index; D016022:Case-Control Studies; D004032:Diet; D004522:Educational Status; D002149:Energy Intake; D005260:Female; D044950:Flavanones / Q000008:administration & dosage; D005419:Flavonoids / Q000008:administration & dosage* / Q000032:analysis; D044948:Flavonols / Q000008:administration & dosage; D006801:Humans; D007529:Isoflavones / Q000008:administration & dosage; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000453:epidemiology*; D010610:Pharyngeal Neoplasms / Q000453:epidemiology*; D012307:Risk Factors; D012907:Smoking
D000872:Anthocyanins; D044950:Flavanones; D005419:Flavonoids; D044948:Flavonols; D007529:Isoflavones