An allogeneic cancer vaccine composed of lethally irradiated whole melanoma cancer cells that are genetically modified to secrete the immunostimulatory cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF), with potential immunostimulating and antineoplastic activities. Upon intradermal injections, allogeneic GM-CSF-secreting lethally irradiated whole melanoma cell vaccine secretes GM-CSF. In turn, GM-CSF may stimulate the body's immune system against tumor cells by enhancing the activation of dendritic cells (DCs) and promoting antigen presentation to both B- and T-lymphocytes. In addition, GM-CSF promotes antibody-dependent cellular cytotoxicity (ADCC), and increases interleukin-2-mediated lymphokine-activated killer cell function.