Studies on a human malignant thymoma Part 2. Heterotransplantation of a human malignant thymoma (epithelial type) cell line into hamsters

A continuous cell line, which was designated as MT-TY, was established from an explant culture of human malignant thymoma (epithelial type) in our laboratory. In the present study, for the purpose of making an animal model of human malignant thymoma, MT-TY cells were transplanted into antilymphocyte serum-treated newborn hamsters. The MT-TY line was serially transplanted for 7 passages. When 1.2-11.0×10(6) cells were inoculated intraperitoneally, all of the 22 experimental animals developed invasive tumors. Of the 22 hamsters, ascites and pulmonary metastases were found in 16 and 4 hamsters, respectively. Histological characteristics of the tumors in hamsters were similar to those of epithelial type of human malignant thymoma. This animal model would be useful for various studies of human malignant thymoma.