Monoclonal Antibody Therapy Plus BCG in Treating Patients With Limited-Stage Small Cell Lung Cancer

DISEASE CHARACTERISTICS: * Histologically or cytologically confirmed limited stage small cell lung cancer (SCLC) * Completed first line combination treatment consisting of at least a 2 drug chemotherapy regimen (4 to 6 courses) and a chest radiotherapy regimen * Must have achieved clinical response (complete or partial) with no evidence of progression or relapse PATIENT CHARACTERISTICS: Age: * 18 and over Performance status: * Karnofsky 60-100% Life expectancy: * Not specified Hematopoietic: * WBC greater than 3,000/mm\^3 * Platelet count greater than 100,000/mm\^3 Hepatic: * AST less than 1.5 times upper limit of normal * No hepatitis B Renal: * Not specified Other: * No history of tuberculosis * Purified Protein Derivative negative to at least 5 IU * HIV negative * No severe active infection * No active infections requiring systemic antibiotics, antiviral, or antifungal treatments * No serious unstable chronic illness * No other prior malignancy within the past 5 years except adequately treated carcinoma in situ of the cervix or nonmelanomatous skin cancer * No psychological, familial, sociological, or geographical condition that would preclude study * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception PRIOR CONCURRENT THERAPY: Biologic therapy: * At least 4 weeks since prior immunotherapy * No prior therapy with mouse proteins * No other concurrent immunotherapy before first disease progression Chemotherapy: * See Disease Characteristics * No concurrent chemotherapy before first disease progression Endocrine therapy: * No concurrent systemic or chronic corticosteroids Radiotherapy: * See Disease Characteristics * No prior radiation to spleen * No concurrent radiotherapy before first disease progression Surgery: * No prior surgery for SCLC * No prior splenectomy Other: * At least 4 weeks since prior combination therapy * No prior second line therapy for SCLC * At least 4 weeks since other prior investigational agent * No concurrent systemic antihistamines or nonsteroidal antiinflammatory drugs * No concurrent immunosuppressant therapy before first disease progression