Correlation between gender and spontaneous C-cell tumors in the thyroid gland of the Wistar rat.
In many rat strains, C-cell hyperplasia occurs in an age-dependent manner and is often associated with multifocal C-cell carcinoma. The purpose of this study was to investigate the spectrum of spontaneous, proliferative C-cell disorders by gender in Wistar rats throughout their lifespan. The incidence of C-cell hyperplasia shows a significant increase with age (P<0.001) and is much higher in female rats than in male rats (P<0.05). From 3 to 24 months of life, 27.5% of female rats showed a normal C-cell pattern, 55.0% showed C-cell hyperplasia, and 17.5% showed C-cell tumors; while 57.5% of male rats showed a normal C-cell pattern, 32.5% showed C-cell hyperplasia, and 10% showed C-cell tumors. Although the overall frequency of C-cell neoplasms in females was nearly double that in males, these data are not statistically significant. However, the number of C-cell tumors showed a significant increase with age (P<0.05). Therefore, we can conclude that there were significant differences in the incidence of the total spectrum of C-cell proliferative abnormalities in the thyroid gland of Wistar rats that were both age-dependent and gender-dependent.
Martín-Lacave
I
I
Departamento de Citología e Histología Normal y Patológica, Facultad de Medicina, Universidad de Sevilla, Av. Sánchez Pizjuán s/n, E-41009 Seville, Spain. ilacave@cica.es
Bernab
R
R
Sampedro
C
C
Conde
E
E
Fernández-Santos
J M
JM
San Martín
M V
MV
Beato
A
A
Galera-Davidson
H
H
D000375:Aging / Q000473:pathology*; D000818:Animals; D018276:Carcinoma, Medullary / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D005260:Female; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012737:Sex Factors; D013964:Thyroid Neoplasms / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology