The Relation of the Hypophysis to the Growth of Malignant Tumors Iv. a Study of the Influence of Nutritional Factors on Walker Tumor

Since pituitary ablation has been shown to influence the rate of growth of transplanted (1-4) and autogenous (5) rat tumors, several investigators (6, 7, 8) have made an effort to define the factors by which this effect is produced. The numerous physiologic and anatomic changes which follow hypophysectomy contribute to make the problem complex. The present study is concerned with an appraisal of nutritional factors. McEuen and Thomson have previously observed the influence of degrees of starvation on the rate of growth of Walker tumor 256 and compared their results with the same tumor in hypophysectomized animals. They concluded that starvation may retard tumor growth as much as hypophysectomy. From the data presented, however, there was some question as to the validity of this conclusion (7, 5). We have attempted to restudy the question, using a technic of feeding which we believe increases the accuracy of the experiment.