[Principles for adjuvant and neoadjuvant chemotherapy]

Early systemic therapy, either immediately after treatment of the primary tumor with surgery (adjuvant chemotherapy) or as initial treatment before local control (neoadjuvant chemotherapy) has been carried out to attempt to eliminate occult micrometastatic disease. The principal goal of adjuvant/neoadjuvant treatment is to increase the effectiveness of treatment over what can be obtained from surgery alone. The primary endpoint of interest is survival. Disease- or recurrence-free survival is often used as a surrogate measure of survival. Adjuvant/neoadjuvant chemotherapy studies generally employ regimens that have appeared most active against the same tumor in advanced stages. The doses and schedules used in the adjuvant setting have also paralleled those for advanced disease. Recently, a prospective randomized study of adjuvant chemotherapy in the patients with breast cancer have shown that the increase of dose intensity of chemotherapy lead to improved disease-free and overall survival. Moreover, prospective randomized studies are needed to support timing decisions for adjuvant/neoadjuvant chemotherapy. While awaiting the appearance of more effective drugs and more sensitive staging techniques, we should continue to investigate variations of dose and schedule of adjuvant/neoadjuvant chemotherapy.