HYDATIFORM DEGENERATION IN TUBAL AND UTERINE PREGNANCY. 329 



only. The same thing is true also of the villi in the early stages of hydatiform 

 degeneration and maceration, especially when the latter masks the former. The 

 difficulty would be still greater in case of whole chorionic vesicles which are almost 

 completely dissolved, leaving only a shadow picture formed by a coagulum without 

 nuclei, which nevertheless may retain almost perfectly the form of the chorionic 

 vesicle and of the individual villi. It may long be impossible to differentiate such 

 cases as these, but they form only a relatively small proportion of the whole. The 

 many cases both of uterine and tubal chorionic vesicles which still were implanted 

 and show exceedingly fine instances of hydatiform degeneration, as well as the many 

 splendid examples of groups of villi which were still implanted in the tube or in the 

 decid.ua, and which were equally good examples of hydatiform degeneration, leave 

 no room for doubt as to the frequency of occurrence of this condition, even after 

 due allowance is made for the doubtful cases. 



Werth further concluded that not one of the 7 cases of chorio-epithelioma 

 regarded as having arisen from tubal pregnancies recorded before 1904 was suffi- 

 ciently authenticated. Nevertheless, by 1910 Veit felt justified in saying that a 

 considerable number of cases of chorio-epithelioma arising from tubal pregnancies 

 had been described. He added that Risel (1895) gathered 11 cases from the litera- 

 ture and that the second case had been reported since Risel's paper. Since my 

 interest in the subject is largely incidental, I have not taken the trouble to gather 

 from the literature cases of chorio-epithelioma alleged to have arisen from tubal 

 pregnancies which may have been reported since Veit wrote. Moreover, I could 

 not presume to judge these cases critically. Hence I will accept the fact that chorio- 

 epithelioma arising from tubal pregnancy is regarded as established by a number 

 of investigators. If the conception regarding the relation of chorio-epithelioma to 

 hydatiform mole is justified, then the occurrence of hydatiform degeneration in 

 tubal pregnancy must follow on a priori grounds alone. Moreover, whatever the 

 causes of hydatiform degeneration may be, one possibly is safe in assuming that the 

 condition is not restricted to the uterus, and when I noticed that hydatiform 

 degeneration was so very common in young uterine abortuses the surmise that it 

 might be still more common in cases of tubal pregnancy seemed justified. Since 

 over 100 specimens of tubal pregnancies from the Mall Collection were included 

 in the survey originally planned by him, a study of these specimens formed an 

 excellent opportunity for observations on this subject. 



That the case of Otto, with its pathetic history, really was one of hydatiform 

 mole, can not be doubted in view of the careful description of the whole case its 

 clinical history, necropsy, and the histologic examination. This case is interesting 

 also because the degeneration was in its early stages, the hydatids being only as 

 large as a pinhead and the embryo still being present. Moreover, from Otto's 

 description it is very likely that the specimen contained Hofbauer cells which I have 

 discussed elsewhere (Meyer, 1919). 



The history of the case observed by Wenzel in 1855 and reported in 1893 is 

 equally complete and equally pathetic, as could be surmised by all familiar with 

 the history of tubal pregnancy. In this case the mole was as large as a "hen egg," 



