To decrease side effects, we used chronomodulation to administer the second course of adjuvant chemotherapy to two patients with advanced oral cancer who had severe side effects during the first course. During the first course, chemotherapy was administered according to a conventional schedule, and during the second course chemotherapy was based on the circadian rhythms of the human body (chronomodulation). The first patient, a 58-year-old woman with squamous cell carcinoma in the left side of the tongue, received two courses of adjuvant chemotherapy (CDDP 80mg/m<SUP>2</SUP>, day 1+5-FU 800...