Adjuvant chemotherapy of head and neck cancer: the past, the present, and the future.

In the past two decades, overall survival of head and neck cancer patients has not improved significantly, despite improvements in surgery and radiotherapy techniques. In the early stages, head and neck cancer can be cured with surgery and/or radiotherapy. However, in patients who present with locally advanced lesions after combined surgery and radiation treatment, local recurrences develop in 50% to 60%, distant metastases in 20% to 30%, and a second primary neoplasm in 10% to 40%. Five-year survival for patients with stages III or IV disease who undergo standard treatment ranges from 0 to 60%. Traditional chemotherapy has been used for those patients with recurrent disease after surgery and/or radiotherapy, but the results have been disappointing. Therefore, chemotherapy as an induction regimen has been incorporated into combined modality treatment. The following specific issues of adjuvant chemotherapy will be addressed: (1) rationale for theoretic advantages of induction chemotherapy in head and neck cancer; (2) critical review of controlled and uncontrolled studies of adjuvant chemotherapy; (3) sequential chemotherapy and radiotherapy; (4) simultaneous chemotherapy and radiotherapy in head and neck cancer; (5) issues of surgical and radiotherapy complications following induction chemotherapy; (6) ongoing clinical trials of chemotherapy in head and neck cancer in the United States; (7) development of effective induction regimens in head and neck cancer; (8) future directions of adjuvant chemotherapy in head and neck cancer.