DISEASE CHARACTERISTICS: Histologically confirmed malignancy that is stage IV and/or at high risk of recurrence despite standard treatment Stage IV malignancy that is surgically rendered free of macroscopic tumor allowed if current available treatment is not likely to offer a survival advantage or result in significant palliation If at high risk for recurrence, must have an estimated recurrence rate of at least 75% following definitive therapy, such as: Postresection of pancreatic cancer Gastric cancer with regional lymph node involvement Node positive stage II or stage III esophageal cancer Stage IIIA or IIIB non-small cell lung cancer Breast cancer with at least 10 positive axillary nodes Must have low tumor burden or no evidence of disease Must have evidence of prior vaccinia (for smallpox immunization) Must have CEA expressing type tumor or a serum CEA elevation of 10 or greater during course of disease No CNS metastases Hormone receptor status: Not specified