Neoplastic Growths 267 



imiioi, the number of "takes" being decreased. Colchicine (1 nig/kg) 

 administered 15 hours before irradiation (188 r. twice weekly) in- 

 creased also the effects of X-rays as measiued by the size of tumors in 

 surviving animals. No similar increase in mice and rats, even with 

 large doses of colchicine, was found.^- In the Yale carcinoma of the 

 mouse, 2 mg/kg produced extensive necrosis and hemorrhage, but a 

 border of viable tissue was always seen to persist.^^ The addition of 

 2500 r. produced only a slightly higher rate of curability "not signifi- 

 cant to warrant further investigation." •^- In the Ehrlich carcinoma, 

 colchicine was injected every day (5 mg.) and 260 to .^00 r. delivered. i' 

 Some results seemed to indicate an improvement of the colchicine 

 action by X-rays, which alone are not effective. However, if the dose 

 of irradiation was increased, the life span of the colchicinized mice 

 became shorter than the nontreated controls. From Table 9.2, it is 

 clear that no significant improvement is obtained by combining the 

 two treatments. It must, however, be pointed out that this is a radio- 

 resistant tumor, not well suited for such studies. 



One paper mentions that in a case of gastric carcinoma, two metas- 

 tases were irradiated with the same dose of X-rays, while one was 

 injected with colchicine; the post-mortem disclosed that the latter was 

 severely necrotic, a fact which is not surprising in view of a large 

 local injection of colchicine and which does not demonstrate a true 

 synergism between the two agents. ^'^ 



The action of colchicine on human tumors has been followed by 

 nndtiple biopsies.^-'' The patients were injected intramuscidarly with 

 2 mg. of colchicine. An increase of the metaphase percentage was 

 noted, as well as some hemorrhage and cells with highly polyploid 

 mulei. These data, which are supposed to open the way towards a 

 treatment with colchicine and X-ray combined, were not examined 

 critically, and the variations observed may be entirely fortuitous. 



A series of clinical rej)orts have been published-^^, 49, 43 about 

 colchicine increasing the effectiveness of X-rays, but these results are 

 not statistically valid and cannot be accepted without finther re- 

 search. Colchicine was used for some time as a routine in irradiated 

 cancerous patients at the Cancer Hospital, Brussels, with no convincing 

 results (unpublished) . 



/0.7-2; Plant overgroivtlts. In plants, experimental work'^^ brings 

 some significant detailed cytological data on the action of irradiation 

 on mitoses previously arrested by colchicine, which ai:)pear to be ab- 

 normally fragile. Root tips of Fisiim satimnn and Allium cejxi were 

 dipped into a 1:2000 sohuion of the alkaloid, and irradiated (3500 r. 

 in one minute) at various intervals later. Prophases were observed 

 to be quite resistant, but the c-metaphases were very rapidly modified, 

 the chromosomes clumping together and later undergoing katachro- 



