1) First of all I must take the question of whether the transplantation of Yoshida sarcoma is caused by the tumor cell itself.
In the experiments with ascites free from cells, only one case out of 15 presents the positive result. Even a single case resulting in a success puts before us a question to be discussed-a question of whether there exists a certain extracellular oncogenic agent such as a virus in this tumor.
Supposing such an agent exists in this tumor, the fluid containing the more of it must present the higher transplantability. As a matter of fact, the tumor ascites diluted 4-17 times, in which a great deal of such an agent, if it exists, might presumably have been contained, bore the negative result with one exception in 15 cases, when tumor cells had been excluded from it; while, the tumor ascites diluted to such a high degree as 5 million times produced the positive result, when a very few tumor cells, even a single one, had been included in it.
If such an agent really exists, moreover, the transplantability of this tumor can not be influenced by the number of the tumor cells, but, in fact, it markedly goes down according to the gradual decrease of the number of tumor cells.
From these facts, it is hardly to be believed that there exists any such extracellular oncogenic agent at all.
Besides, tumor cells were occasionally found in a droplet taken from the supernatant by the centrifugation for 60 minutes at 3, 000 cycles. Although such a cell-containing droplet was omitted, absolute prevention from an entrance, among numerous droplets, might not always be expected. If once this droplet containing cells was inoculated into the peritoneal cavity, it would be an easy task for the cell to proliferate immediately, since 1 or 2 cell inoculation caused the positive result.
Furthermore, from the microscopic findings, the proliferation of tumor cells implanted was seen every time, while the picture of malignant transformation of normal cells in the peritoneal cavity could never be observed.
The course of the disease in the one positive case mentioned above (i. e. positive case in cell-free inoculation) was quite analogous to that of 1 or 2 cell inoculation.
I came thus to the conclusion that the transplantation of Yoshida sarcoma does not depend upon any extracellular oncogenic agent, but upon the proliferation of the implanted tumor cell itself.
2) Next I want to express my opinion on the minimal number of tumor cells necessary for the transplantation of Yoshida sarcoma. Table 10 is compiled, from the results of the transplantation with a small number of tumor cells. Although a successful transplantation could be expected even from one single tumor cell, the positive result was not attained in every case where less than 10 tumor cells were applied and even 23 or 30 cells produced the negative result.
These seem to be due to the following conceivable factors: not all cells used for inoculation were viable or capable of proliferation, one single cell sucked into the micropipette might happen to be a normal cell (monocyte or lymphocyte) occurring among tumor cells; furthermore, the cells once sucked into the micropipette might possibly remain there, failing to reach the peritoneal cavity of a rat, or they might be injured during the process of manipulation and fall into degeneration, though they reach the peritoneal cavity.
In this connection, it was remarkable that successful inoculations were made with such a very small number as 1, 2 or 11 of cells, when the tumor ascites was diluted with physiologic NaCl solution with peritoneal fluid of normal rats as an addition. In other words, it may be supposed that the solution added with peritoneal fluid would work less injury to the cells than plain Tyrode solution or physiologic NaCl solution.These results correspond with the report of Furth and Kahn that with Tyrode solution solely,

View full abstract

1. Report has been made on two new cases of carcinosarcoma of stomach, also recording what Furukawa of our department has previously reported on.
2. The above three cases all show the tumors which chiefly infiltrated the deep layer of stomach wall and partly protruded in the lumen of stomach, giving the appearance of the tumor partially replacing the mucous membrane. From histological view, they are composed of round or spindle-shaped cell sarcoma and medullary cancer (in part scirrhus or adenocarcinoma); the two components, in some portions, can be clearly distinguished from each other, but in most cases naturally transform to each other or well mixed up, showing no parenchyma-stroma relation.
3. All these three belong to R. Meyea's Combination tumor, originated in entoderm-mesenchymal germ left behind in the course of normal embryonic growth. However, in the second and third cases, signetring cell formation is seen in a part of the sarcoma, too, giving rise to the question whether this be originated in the epithelial cells scattering mixedly in the sarcoma or those sarcomatous cells be also really epithelial in nature, participating in signetring cell formation. Thus it is impossible for us to determine this as carcinosarcoma. The first case, nevertheless, should be determined as carcinosarcoma, since no such signetring cell formation is seen in the sarcoma.
4. There have been only twelve cases of carcinosarcoma reported, including mine, up to the present. The sexual variance is 6:6; the average age 50.4. As to the origin of development, pyloric region comes first, there being 7 cases of it. Metastasis is seen in 8 cases out of 12, among which 5 are of the same structure as primary tumor, two carcinoma alone, one unexamined.
5. Macroscopic classification: The specially noticeable macroscopic characteristic is the marked thickening of the stomach wall. I have classified carcinosarcomas into 3 types according to the condition of the stomach wall.
A-type: Those which show chiefly the general thickening of the stomach wall.
B-type: Those which develop toward the outside of the stomach wall.
C-type: Those which develop toward the inside of the stomach wall. Dividing this up into two sub-types we get:
1) Those which show a number of semi-globular or fungous swellings in the stomach cavity.
2) Those showing isolated fungous or crater-shaped swelling in the stomach cavity.
6. Although it is both ideal and necessary to classify carcinosarcomas by formal genesis, it is extremely difficult as well as inconvenient to determine it by means of microscopic picture. I suggest a method of classification on the purely morphological stand point, that is:
1st type: Those in which pure carcinoma and pure sarcoma occupy the greater part separately, the two showing mutual contact and mixture only in a minor part. This kind is consisted of two sub-types: that in which carcinoma and sarcoma have their mutual contact outside, and that in which one surrounds the other.
2nd type: The carcinoma and the sarcoma keep parenchyma-stroma relation. Here and there pure carcinoma and pure sarcoma occupy different parts separately, mostly showing parenchyma-stroma relation.
3rd type: Pure carcinoma and pure sarcoma being present in a minor part separatery, the two quite naturally turning to each other, showing no parenchymastroma relation.

View full abstract

1. The influence of monoiodoacetic acid and sodium fluoride on the experimental sarcoma production by way of subcutaneous injection of concentrated glucose solution was tested. Monoiodoacetic acid accelerated the sarcoma production, shortening the period and increasing percentage of the tumor formation, while sodium fluoride had no such effects.
2. From our assumption that the monoiodoacetic, acid and sodium fluoride are acting to interrupt the ferment system of sugar metabolism in a certain stage, it may well be concluded on account of our results that the sarcoma producing hexose is only effective, when it acts in the stage before its breakdown to triose.
3. The dosage of monoiodoacetic acid and sodium fluoride here used did not effect any disturbance to the general nutrition of the experimental animals.
4. Nishiyama, who succeeded for the first time in the sarcoma production with concentrated glucose solution, used at the same time o-amidoazotoluene to yield good results. So we also used it as an olive oil solution in the same sense, but by way of subcutaneous injection to know accurate amount absorbed in the body, instead of the peroral application as Nishiyama.

View full abstract

1. For the cultivation of Yoshida sarcoma the medium of chicken plasma and chick embryo juice with the addition of rat ascites is most suitable. Addition of a piece of chick embryo heart is also excellent.
2. Other than rat ascites, spleen extracts from normal rats act as growth promoter. Spleen extracts from tumor bearing rats are less effective. Extracts prepared from brain, testis, liver, etc., do not permit the growth of the sarcoma.
3. Tumor reimplanted into the peritoneal cavity, after the removal of the tumor previously successfully implanted in the same rats subcutaneously, resulted in negative, demonstrating the development of immunity. The re-implanted sarcoma cells in these experiments survived generally 2 or 3 days but never more than 6 days in the peritoneal cavity.
4. Injections of tris-β-chloroethylamine into 7 cases resulted in the disappearance of sarcoma cells within 2 days after the first injection. However, due to the strong secondary action no marked prolongation of life was obtained. The suitable doses of nitrogen mustard may be 0.1mg or less per 100g body weight.
5. In 10 cases treated with placenta preparation there was 1 in which the tumor regressed, and in 1 other there was the prolongation of life to 60 days.
6. Estrin was injected subcutaneously into 7 cases in which sarcoma was successfully implanted into testis. Tumor disappeared in 2 of these cases.
7. The tumor was not influenced by mixed typhoid-paratyphoid vaccine, benzene, etc. Placenta preparation and estrin certainly produced regression of tumors in some cases, but the results were not constant.
8. The regressive changes found in sarcoma cells intraperitonelly injected into animals which were previously successfuly implanted subcutaneously and from which the resulting tumor removed, were identical with those frequently met with in the terminal stage of the usual positive transplantation in normal rats, and there was nothing characteristic about the sarcoma cell changes in immunized animals.
9. In the case of retransplantation in the peritoneal cavity, after the removal of previously implanted subcutaneous sarcoma, granulocytic reaction disappeared in 1 or 2 days, followed by the rapid reciprocal increase of mononuclear cells, in which stage vacuolization of mononuclear cells, appearance of phagocytic cells and desquamation of the lining cells of peritoneum were conspicuous.
10. Sarcoma cells show neutral red rosettes, surrounded by rod-shaped Janus green stained bodies. In some cells the Janus green stained bodies alone, without the neutral red rosette, are seen probably representing younger forms.
11. The Janus green and neutral red stained bodies and granules appear most markedly during 2-3 days after transplantation, and they tend to be less numerous during the middle to terminal stages.
12. Cells not showing stained granules with Janus green-neutral red double supravital technique, if transplanted to a new host, will suddenly show these stained structures, which may be regarded to have some relation to the changes in cellular function or in growth environments.
13. Granules in the sarcoma cells in fixed specimens stained with acid fuchsin or iron hematoxylin are of rod or granular form, scattered in the cytoplasm. Nucleoli are large, of complex form, and occur in irregular numbers.
14. When sarcoma cells do not show stained granules with Janusg reenneutral red double staining, the addition of certain solutions, such as physiological saline, Ringer's, CaCl₂, MgSO₄ or KCl in certin concentration, vitamin B₁, glucose, saliva, chicken serum, etc., induces the appearance of Janus green stained granules.

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract