Relationship between mammary tumourigenesis and uterine adenomyosis in four strains of mice.

The development and the progression of uterine adenomyosis were compared with those of mammary tumours in four strains of mice with different mammary tumour potentials. Cumulative mammary tumour incidences were the highest and the lowest in SHN and C3H/He, respectively, and intermediate in SLN and GR/A. However, the growth rate of palpable mammary tumours was higher in SHN and SLN than in GR/A and C3H/He, between which no difference was observed. SHN was also higher than SLN in this parameter. While almost all mice bearing mammary tumours developed adenomyosis in all strains, there was an apparent strain-difference in the progression of this lesion which paralleled well that of mammary tumours. All results indicate the intimate relationship between the development and the progression of both lesions in mice.