title: Oral squamous cell carcinoma in ad libitum-fed and food-restricted Brown-Norway rats.
abstract: A high incidence of oral squamous cell carcinoma was present in male and female Brown-Norway rats fed ad libitum or food-restricted dietary formulations. One hundred eight-nine rats were examined from 4 dietary treatment groups: male ad libitum, male food-restricted, female ad libitum, and female food-restricted. The ad libitum treatment groups for both males and females had significantly more cases of oral squamous cell carcinoma than cohort food-restricted groups. In ad libitum rats, 10 of 47 (21%) males and 15 of 47 (32%) females had oral squamous cell carcinoma, whereas only 4 of 47 (9%) males and 5 of 48 (10%) females in the food-restricted groups were similarly affected. The food-restricted rats lived significantly longer than ad libitum cohorts, so the higher incidence of squamous cell carcinoma was not dependent on extended lifespans. In addition to the dietary influence, a significant difference in oral squamous cell carcinoma incidence occurred between various familial lines. Family lines having representatives in both ad libitum and food-restricted groups had lower oral squamous cell carcinoma incidences in the food-restricted group whether comparing affected litters or individuals. Results suggest that the incidence of oral squamous cell carcinoma in our colony of Brown-Norway rats can be influenced by both the dietary treatment group and genetic predilection within certain pedigrees.
authors.affiliation: Pathology Associates, Inc., Jefferson, Arkansas 72079, USA.
authors.forename: J D
authors.initials: JD
authors.lastname: Thurman
authors.forename: D L
authors.initials: DL
authors.lastname: Greenman
authors.forename: R L
authors.initials: RL
authors.lastname: Kodell
authors.forename: A
authors.initials: A
authors.lastname: Turturro
mesh_terms: D000821:Animal Feed / Q000009:adverse effects*; D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology / Q000473:pathology* / Q000662:veterinary*; D004435:Eating; D005260:Female; D005508:Food Deprivation; D015994:Incidence; D008297:Male; D009062:Mouth Neoplasms / Q000453:epidemiology / Q000473:pathology* / Q000662:veterinary*; D051381:Rats; D011914:Rats, Inbred BN; D012376:Rodent Diseases / Q000453:epidemiology / Q000473:pathology*