rozen Storage of 34 Various Solid and Ascites Tumors

A variety of transplantable mouse, rat, hamster, and ehieken tumors have been suecessfully stored at 7 6 ~ C. (dry-ice chest) for a period of 1 year. These tumors are seven sarcomas, a mammary carcinoma, a skin carcinoma, a bladder carcinoma, a lung carcinoma, two lymphosarcomas, a glioma, a leukemia, a virus leukemia, a pancreatic tumor, and a small intestine tumor. Transplantability of a majority of mammary-type tumors was greatly damaged by frozen storage at 7 6 ~ C. Transplantability of very slowly growing tumors--namely, Harding-Passey melanoma, Andervont hepatoma, Iglesias functional ovarian tumor, and Iglesias functional adrenal tumor---was either completely or almost completely abolished by frozen storage at 7 6 ~ C. for 8 months. The viability of Ridgway osteogenic sarcoma was completely destroyed by frozen storage for 1 month at 7 6 ~ C. Transplantability of Wagner osteogenic sarcoma was markedly reduced following storage at 7 6 ~ C. The viability of Ridgway osteogenic sarcoma was almost completely destroyed by frozen storage for 1 day at 7 6 ~ C. or 2 5 ~ C. Maintenance of this tumor for 1 day at 4~ ~ C. did not alter its transplantability. Hauschka's slow freezing technic (from 0 ~ C. to ~ 5 ~ C.) of neoplastic tissues appears to be less harmful to the viability of frozen tumor (Ridgway osteogenic sarcoma) than the technic of freezing described in the present report.