In our helplessness in regard to the causes of the origin of tumors, we have left no way untrodden by which we could possibly find a point of support. Thus we have sought to find whether tumors develop more fre quently in one breast or the other, or whether there is no difference in the two organs. Velpeau noted that of 362 carcinomas, 156 were right, 191 were left, and 15 were bilateral. I found in 245 cases, 123 right, 119 left, and 3 bilateral. The sum of both series of observations (607 cases) gives 279 right, 310 left, and 18 bilateral. According to this car cinoma would be slightly more frequent on the left side; but the differ ence does not seem to me great enough to base hypotheses on. It is strik ing that of the cases of fibroma, adenoma and cysto-sarcoma (32 in all) in which I have noted the affected side, there were 9 right, 19 left and 4 bilateral, showing a preference for the left side (in my special statistics of carcinoma, however, there is a slight preference for the right side).
Completely contradictory to what has been said are the statistics of Hennig. He has brought forward a number of cases which certainly seem to prove the opposite to ours. When we consider his statistics of the forms of carcinoma alone, it is seen that of 853 cases, 560 were right, 270 left, and 23 bilateral; and by later statistics 867 right, 538 left. This enor mous difference in favor of the right side leads him to bui:d up hypothe ses as to the cause of these phenomena, which, from anatomical points of view, may seem plausible. But it is not shown how his statistics were collected, whether they really contain continuous series of observations from hospitals, or whether they also contained occasionally published individual cases, so we cannot accept his statistics as scientifically applica ble without further confirmation.
Of greater value would be statistics as to the time of life at which tumors of the breast, especially carcinomata, appear. I group the figures of Velpeau, Birkett and myself as follows: But to estimate the percentage without these series of observations for more exact comparison, it is seen that the number of patients affected is by far the greatest in the fifth and sixth decennium (41-60). Still, not only within this time, but also before and after it there are not incon siderable differences in the three series. But I can scarcely believe that it is the difference of the absolute size of the figures, in which the fault lies. For example, if I take my Zurich statistics alone, and then von Wini warter's statistics alone, these casual divisions of my observations give the same result as the above series. The greatest number always falls in the time from forty-one to sixty years of age. According to von Wini warter's estimated series of observations as to the period of life, it is es pecially between the ages of forty-one to forty-five that mammary carci noma is most frequently developed. Now this does not correspond to
Velpeau's observations. (The small series of statistics of Volkmann cor responds with that of Velpeau.) According to him the time of most frequent affection is from fifty-one to sixty years. Still more striking is the frequent occurrence of mammary carcinoma in the third and fourth decennium in my series, while in Velpeau's series this age is far less frequently affected; it is so much the more striking, as many soft sarco mas may have slipped in under Velpeau's " encephaloides," which more frequently occur in younger women.
Opposed to these peculiar, and it seems to me indisputable facts, we may perhaps point to the relations of the mammary glands to the sexual organs. I would at the same time emphasize more forcibly than Al. von Winiwarter has, that the greater part of my material for observation has been from the Galician and Hungarian Jewesses, in whom sexual matur ity doubtless comes on much earlier than in French women; whether it is also extinguished earlier as a rule, I unfortunately cannot state positively, and yet it would be of importance to know this if we wish to compare the development of carcinoma with the climacteric. It is not uncommon for Hungarian Jewesses to menstruate in the eleventh year. Probably the menses usually cease in the middle of the fortieth year; yet I have met with Jewish women who still menstruated regularly in the sixtieth year, and in whom the first menstruation occurred in the tenth year. One thing seems settled, that no true mammary carcinoma has been ob served before the beginning of menstruation. Further, all the cases of mammary carcinoma before the thirtieth year, of which I have known, occurred in married women. And against the statement, that the largest number of mammary carcinoma appear toward the end of the period of menstruation, and at a time, therefore, when the mamma begins to re trograde, no valid objection can be made.
These observations are also somewhat affected by the fact that mam mary carcinomas in men, rare as they are, appear as a rule in the fifth and sixth decennium, and there can scarcely be any question as to retro gression in these periods. The same holds good for carcinoma of the skin. Therefore the development of carcinoma of the mammary gland (which may always be regarded as a cutaneous gland) coincides generally with the time of development of carcinomas, so that, without regard to the incontrovertible especial frequency of carcinomas in the mammary gland, we can also explain away the connection with the functions of the genital apparatus.