228 STUDIES ON PATHOLOGIC OVA. 



Robertson (1915) quoted Findlay as finding that 16 per cent of 250 hydatiform 

 moles collected from the literature were followed by malignant disease. Briggs, 

 who reported 21 cases of hydatiform degeneration with 2 of chorio-epithelioma, or 

 an incidence of malignancy of 9.5 per cent, called attention to the "diminishing 

 ratio in the tendency to malignancy" shown by his series. 



Findlay (1917) stated that chorio-epithelioma developed in 131 out of 500 cases 

 gathered by him from the literature, which is an incidence of 26.2 per cent, but, 

 as already stated, most of these cases from the literature are old, advanced degenera- 

 tions, many of which have been retained for a long time. The tendency to malig- 

 nancy in these probably can in no way be compared to that in smaller and younger 

 specimens, many of which are aborted entire with the surrounding decidua. 

 Consequently it need not surprise us that out of 19 cases of this series, in which 

 later reports were obtainable, none was reported as having developed chorio- 

 epithelioma. 



Perhaps I may add a word of caution in regard to a possible change in atti- 

 tude toward the question of malignancy with a consequent relaxation of vigilance. 

 It is true that out of the 21 cases of Briggs only 2 developed chorio-epithelioma; 

 but it must not be forgotten that Briggs in part was, and I to a far larger extent am, 

 dealing with a different class of hydatiform moles than those upon a study of which 

 the prevailing conception of malignancy is based. Hydatiform moles which 

 continue to grow and which survive for months after the death of the embryo 

 evidently are more vigorous, and hence no doubt also more dangerous than those 

 which are aborted early and spontaneously. Since the latter formed the great 

 majority of all moles here considered, opinions regarding malignancy formed on 

 this basis probably would lead to disaster if applied in practice. Such conceptions 

 would be based upon a totally different incidence than the current one of 1 hydati- 

 form mole in every 2,000 cases. Instead of relaxing our vigilance, it would seem 

 wise to increase it, particularly in the cases of so-called spontaneous abortions 

 the cases in which no ascertainable cause for the termination of pregnancy can 

 be found, especially if the chorionic vesicle is empty or if the embryo belongs in 

 one of the early groups of Mall's classification. 



The average age of 36 women aborting hydatiform moles was 31 years. Al- 

 though I do not regard the alleged ages as necessarily the actual ones, this average 

 age agrees very well with that of 6 cases reported by Poten, 10 by Donskoj, 23 by 

 Briggs, 6 by Gromadski, and 8 by Robertson. The average age of Poten's cases 

 was 32 years, of Donskoj 's 25 years, of Brigg's 28 years, of Gromadski's 29.6 

 years, and of Robertson's 28.4 years. Pazzi (1908 b ), on the other hand, stated that 

 Briquel placed the greatest frequency of hydatiform degeneration between 20 and 

 30 years. These averages are so far on the near side of the menopause that one can 

 make liberal allowances for the proverbial disinclination of women to state their 

 exact age, even to physicians, and nevertheless regard the prevailing opinion 

 regarding the greater frequency of hydatiform mole near the menopause undoubt- 

 edly as ill-founded. If, as Lewis and Lewis (1906) stated, it is necessary to add 

 only half a year to the average age of a large group of women in order to ascertain 



