OBJECTIVES: I. Determine if immunization with glycosylated MUC-1 antigen containing MUC-1 (106) with keyhole limpet hemocyanin conjugate plus immunological adjuvant QS21 induces an antibody, helper T cell and/or cytotoxic T cell response against MUC-1 in patients with prostate cancer expressing MUC-1. II. Determine post-immunization changes in PSA levels and other objective parameters or disease (radionuclide bone scan and/or measurable disease if present) in these patients after receiving this therapy.