Abstract
Light microscopic and histochemical investigations were performed on a total of 329 CBA×C57BL/6 F1 hybrid mice which were subcutaneously transplanted with Gardner osteosarcoma 519 between the 80th to the 95th transplant generations. The transplantability was 92.4%, and the survival time was 63±23 days. Metastases were seen only in the lung in 45 (21.0%) of the 214 cases which survived over 40 days. The grafted tumors were palpable at about 10 days and became the size of the head of the little finger at about 50 days after inoculation. When the sizes of the tumors were small they mainly consisted of spindle cells with many mitotic figures, and strong activities of both alkaline and acid phosphatase and PAS reaction-positive glanules were present. Multinucleated giant cells, reticular stroma and osteoid or bone tissues appeared with tumor growth, but the numbers of mitotic figures and the activity of alkaline phosphatase were reduced. Thus, the author classified this sarcoma in four histological types; the spindle cell type, the giant cell type, the reticular stroma type and the osteoid-bone type. The spindle cell type was considered as a proliferating phase and the reticular stroma and osteoid-bone types were as a differentiating phase. The functions of this tumor to form bone or osteoid tissue and to increase the levels of the serum alkaline phosphatase of the host were proved to be retained after 95 transplant generations; therefore, this sarcoma was regarded as a kind of functioning tumor with the above functions.
