Determination of optimal freezing parameters of human prostate cancer in a nude mouse model

BACKGROUND We sought to determine whether more than one freeze/thaw cycle is required and what minimum temperature reliably kills prostate cancer in vivo. METHODS Two human prostate cancer cell lines (LNCaP and PC3) were implanted subcutaneously in male nude BALB/c mice. Tumors were frozen with contemporary cryosurgery equipment and monitored for temperature, size, and serum prostate‐specific antigen (PSA) measurements. The tumors were subjected to one or two freeze/thaw cycles through a wide range of temperatures from 0–−80°C. RESULTS These experiments show that a single freeze/thaw to a temperature