INFECTION AND RESISTANCE 



tion is at present based has justified extensive attempts to establish 

 an analogous empirical method for tumor diagnosis. 



The literature on this question is confusing. A number of ob- 

 servers using antigens variously prepared from tumor substances 

 have reported favorable results. Simon and Thomas 38 report many 

 positive reactions, as do Sanpietro and Tesa, 39 and a number of 

 others. Clowes 40 has carried out a reaction on sarcoma rats and 

 obtained positive reactions in animals in which the tumors were small, 

 negative ones when the tumor had grown to a large size. Ranzi, 

 on the other hand, obtained negative results throughout. Ranzi 41 

 found that normal serum would often give complement fixation with 

 carcinoma extracts, also that many tumor extracts and sera of tumor 

 patients inhibited complement by themselves. The reactions were so 

 irregular that he assumed them to be without value. Recently the 

 subject has been very thoroughly investigated by v. Dungern. 42 



Von Dungern claims to have finally evolved a method by which 

 the diagnosis of malignant disease can be made with reasonable 

 accuracy. Like the Wassermann reaction his method is purely em- 

 pirical. He admits that probably it is not a specific antibody deter- 

 mination and depends rather upon the presence of pathological prod- 

 ucts of metabolism in the sera of tumor patients. The reliability of 

 his method depends upon the observation of a number of details 

 which he has determined empirically. 



He obtains his antigen in a purely non-specific manner, using, 

 as just stated, for this reaction acetone extracts of human blood cells. 

 We take the description of the reaction entirely from his own article 

 in "Weichhardt's Jahresbericht." The antigen is prepared in the fol- 

 lowing way: Blood is taken from a vein, preferably from a para- 

 lytic patient, since v. Dungern claims that individual specimens of 

 blood vary, and he has had the best results with that of paralytic 

 cases. Clotting is prevented by sodium oxalate and the blood cells 

 are thoroughly washed in the centrifuge. To the sediment are added 

 19 volumes of pure acetone (Merck). This is allowed to stand three 

 days at room temperature and is occasionally shaken during this 

 time. It is then filtered, the acetone evaporated in the incubator at 

 37 C., and the residue taken up in 96 per cent, alcohol. This alco- 

 holic extract is diluted before use with four parts of salt solution. Of 

 this final preparation 0.8 c. c. is used in the individual test. 



Particular precautions must also be taken in the handling of the 

 serum of the patient. In his earliest tests v. Dungern determined 



38 Simon and Thomas. Journ. Exp. Med., Vol. 10, 1908. 



39 Sanpietro and Tesa. Cited from v. Dungern in "Weichhardt's Jahres- 

 bericht," etc., Vol. 8, 1912, p. 163. 



40 Clowes. Journ. A. M. A., 1909, Vol. 52. 



41 Ranzi. Wien. kl. Woch., 1906, p. 1552. 



42 V. Dungern. Munch, med. Woch., Nos. 2, 20, 52, 1912; Berl kl. Woch., 

 1913, "Weichhardt's Jahresbericht," Vol. 8, 1912, p. 163. 



