Effects of E2 and Tam treatments on mammary tumor development in female ACI rats.

Column 1 lists different treatments each group of animals received. The number of animals per group (n) is listed in column 2. Percent tumor incidence after 240 days of treatment period is listed in column 3, and the average number of tumors per tumor-bearing animal (tumor multiplicity) is listed in column 4. Column 5 lists the day on which the first tumor appeared in each group (appearance of first tumor). ‘*’ indicates significant difference (pp