Compositions comprising a tissue vaccine that include a mixture of heterogeneous tissue obtained from tumors and connective tissues. Vaccines comprising these compositions are also provided, as well as methods of using the vaccines in the treatment and/or inhibition of tumor growth, and particularly prostate tumor growth and cancers. The preparations may be defined as vaccines comprising tumor cells and connective (stromal) tissues derived from xenogeneic animals. Preparations comprising the tissue vaccines are provided using tissue harvested directly from tumors. Methods for preventing de novo development of cancer are also disclosed. A tissue vaccine comprising glutaraldehyde-(GFT) treated tissue prepared from tumor and connective tissue reduces the incidence of autochthonous prostate cancer. A tissue vaccine comprising a potassium thiocyanate extract (PTE) preparation of a tumor and connective tissue is also provided. The tissue vaccines are demonstrated to reduce the incidence of autochthonous prostate cancer.
