OUTLINE: This is a randomized, multicenter study. Patients are stratified according to center, Karnofsky performance status (60-70% vs 80-100%), and response to first-line combined modality treatment (complete vs partial). Within 3-7 weeks after completion of prior induction chemoradiotherapy, responding patients are randomized to 1 of 2 treatment arms. Arm I: Patients receive best supportive care and are observed until disease progression is documented. Arm II: Patients receive adjuvant monoclonal antibody BEC2 and BCG intradermally on day 1 of weeks 0, 2, 4, 6, and 10. Treatment consists of 5 vaccinations over a period of 10 to 12 weeks in the absence of unacceptable toxicity or disease progression. Quality of life is assessed at baseline, at weeks 6, 12, and 24, and then every 6 months thereafter. Patients are followed every 3 months.