The Action of Buried Tubes of Radium Emanation on Neoplasias I N Plants

The insertion into an animal tumor of buried capillary glass tubes containing radium emanation presents a comparatively new departure in radium therapy and is undoubtedly destined to play a prominent part in the future development of the whole field of radiotherapeutics. The technique employed on animals and human beings is as follows: Radium emanation, the first active product of decomposition of radium, is an elementary body in a state of a heavy gas, and by means of appropriate apparatus may be collected in capillary glass tubes 3 to 5 inm. long, and 0.25 mm. in diameter. These tubes may be made to contain anywhere between 0.1 to several millicuries of radium emanation each. They are inserted into the tumor tissue by aid of a trocar. The tubes exert a comparatively weak but continuous action on the tissues which lasts for several weeks. The cumulative action of 1 mc. when buried permanently in the tissue is calculated to equal 132 mc. hours. The tissue immediately surrounding the capillary is influenced by the soft beta rays and may become necrotic. Figure 1, A , shows such an area of necrosis in the spleen of a rabbit into which a radium emanation capillary was inserted. A priori it is feasible to anticipate that this necrotic area acts as a filter on the soft rays and the next zone of tissue is then influenced only by the hard gamma rays of radium. In the course of the last two and a half years, the senior writer has used this method extensively in his clinical work. As a general rule the insertion of capillary glass tubes in carcinoma