Induction of Pituitary Tumors by Means of Ionizing Irradiation. ∗ †

Abstract

Summary and Conclusions

Pituitary tumors were induced in mice by a single exposure to ionizing irradiation. The greatest incidence occurred among mice exposed to doses of gamma radiation somewhat below the LD₅₀. These Tumors were about four times more frequent among females than among males. Neutrons appear more efficient in inducing these neoplasms than gamma rays, and the data suggest that doses as low as 40- 70 rern may induce such tumors. The period of latency of these neoplasms is very long, the maximum incidence being at 17-25 months postirradiation.