A cancer vaccine consisting of autologous renal cell carcinoma (RCC) tumor cells modified with the hapten 2,4-dinitrophenol (DNP) with potential immunostimulating and antineoplastic activities. Administration of DNP-modified autologous renal cell carcinoma tumor cell vaccine may induce a cytotoxic T-lymphocyte (CTL) response against renal cell carcinoma tumor cells. DNP conjugation may enhance the immunogenicity of weakly immunogenic antigens.