Effect of Ovariectomy, Adrenalectomy and Hypophysectomy on Growth of Spontaneous Mammary Tumors in Mice.

1. The effect of ovariectomy, adrenalectomy, and hypophysectomy upon growth of spontaneous tumors in mice has been studied. 2. Bilateral adrenalectomy alone or combined with ovariectomy produced a complete regression of the tumor in 3.3% and 3.7% of the mice respectively. Hypophysectomy was followed by regression in 11.5%. of mice. 3. All groups in which either adrenalectomy or hypophysectomy was performed, showed a shorter survival time than unoperated controls, even in those mice showing a complete regression of their tumors.