I 



Neoplasia in Experimental Syphilis. 201 



The experimental method employed was as follows: 

 The sheath of the animal was drawn forward to form a pouch into 

 which was instilled 0.05 c.c. of a testicular emulsion rich in spiro- 

 chetes. About 30 seconds were allowed for the emulsion to 

 spread before releasing the sheath. Most of the fluid then ran 

 out and between 0.04 and 0.05 c.c. could be recovered showing 

 that only a thin film of the emulsion was retained. Infection was 

 first indicated by enlargement and induration of the inguinal 

 lymphnodes and later by the development of a general lymphaden- 

 itis with syphilitic lesions in other parts of the body. 



All animals thus far inoculated by this method have become 

 infected. In some of them, enlargement and induration of the 

 inguinal nodes was clearly recognizable within 24 hours after the 

 application of the emulsion. Thus far (5 weeks) only one of the 

 animals has developed a visible lesion on either the penis or the 

 sheath, although several of them have characteristic lesions in the 

 testicles and scrotum. 



The observations on these animals are not yet complete and 

 the full significance of the experiments cannot be ascertained until 

 the course of the infection has been followed much longer. Similar 

 experiments with other mucous membranes are in progress. 



101 (1683) 



Neoplasia in experimental syphilis. 



By WADE H. BROWN and LOUISE PEARCE. 



[From the Rockefeller Institute, New York City.] 



Neoplasia as a sequel to syphilitic infection is not uncommon 

 in man but has never been recorded in an experimental animal. 

 Recently, we have observed an atypical growth arising from the 

 scar of an old syphilitic lesion in the scrotum of a rabbit which 

 may prove to be a neoplasm. 



The animal was inoculated in the scrotum, June 16, 1916. 

 Small chancres developed and then underwent spontaneous re- 

 gression. Several months later, there was a recurrence and the 

 lesion in the left scrotum persisted for some time. In October, 

 1920, there was a slight diffuse infiltration of the left scrotum 



