The present invention relates to a delipidation method employing a solvent system useful for extracting lipids from cancer cells, thereby creating a modified cancer cell particle. Upon delipidation of the cancer cells, a portion of the cancer cell antigens remain intact. These exposed antigens, or epitopes, foster and promote antibody production. The resulting modified cancer cell particle, or portions of the cancer cell, initiate a positive immunogenic response when administered to an animal or human and help to treat, prevent or delay the onset of cancer. The present invention provides autologous and heterologous vaccine compositions comprising the modified cancer cell with a pharmaceutically acceptable carrier. The present invention provides method of administering these vaccines to treat, prevent or delay the onset of cancer.