PRIOR CONCURRENT THERAPY: Biologic therapy: See Disease Characteristics No concurrent immunotherapy Chemotherapy: At least 6 weeks since prior chemotherapy and recovered No more than 1 prior chemotherapy regimen as adjuvant or for metastatic disease No concurrent chemotherapy Endocrine therapy: At least 2 weeks since prior glucocorticoids No concurrent systemic corticosteroids Radiotherapy: At least 4 weeks since prior radiotherapy and recovered No concurrent radiotherapy Surgery: See Disease Characteristics Other: At least 30 days since other prior investigational drugs No concurrent immunosuppressive therapy (e.g., cimetidine) No concurrent chronic antihistamine therapy