A patient-specific cancer vaccine directed against the soluble protein idiotype of an individual follicular lymphoma with potential antineoplastic activity. A patient-specific follicular lymphoma-derived anti-idiotype vaccine may be composed of a patient-specific, synthetic idiotype-related peptide (such as one corresponding to a hypervariable region of an IgG heavy chain) conjugated to the immunostimulant carrier protein keyhole limpet hemocyanin (KLH). Upon administration, this vaccine may induce an idiotype-specific cytotoxic T-lymphocyte (CTL) response against follicular lymphoma cells expressing the idiotype, resulting in tumor cell lysis.