Adjuvant chemotherapy of cancer. A review of its current status

Adjuvant chemotherapy can be defined as the use of drugs immediately after local control therapy to attempt eradication of residual micrometastatic disease. Conceptually, the micrometastatic disease is presumed to be outside the field of surgical excision or the area of curative intent of radiation therapy. Adjuvant chemotherapy designed to eradicate established micrometastases is a relatively new area of clinical research which began to be seriously considered in the late 1960s and reached a peak of enthusiasm a decade later. However, the early promise of adjuvant chemotherapy has not been fulfilled and the entire concept, and its biological underpinnings, are now under re-evaluation. This review considers the biological rationale for adjuvant chemotherapy and the current status of the large-scale clinical trial data base which now exists in 4 major diseases: breast cancer, osteogenic sarcoma, large bowel cancer, and gastric cancer.