The 20-methyl-cholanthrene emulsions were injected to the bone marrow of femur of rats suspended in propylenglycol, rape-oil, croton-oil and saline and the tumor formation was persued during fourty-five weeks.
About ninety subjects were used for the experiments in four groups, such as the propyleneglycol's (P), the rape-oil's (R), the croton-oil's (C) and the saline's (A). The results obtained were followings.
1) The neoplastic findings in four groups were as follows. For A group, no neoplastic findings were appeared in 10 subjects, for P group, neoplastic findings were appeared 10 cases in 45 subjects, for R group, 8 cases in 22 subjects, and for C group, 9 cases in 15 subjects.
2) To classify the locations of tumors in the diaphysis region and in the epiphysis one, 21 cases were belonged to the former and 6 cases to the latter.
3) To classify the patterns of tumors, 18 cases were belonged to the polymorph-cell sarcoma, 7 cases to the fibrosarcoma and 2 cases to the spindlecell sarcoma.
4) For the rats with tumor formation, various marked changes were observed roentgenologically.
5) No metastasis to the other organs was found.
6) The transplantation of the tumor to the other subjects were succeeded in 3 cases.