New Option for Metastatic Colorectal Cancer: Oxaliplatin and Novel Oral S-1 Combination Chemotherapy

Abstract

Patients and methods EligibilityEligible patients met all of the following criteria: presence of unresectable, metastatic, histologically confirmed colorectal cancer; age from 18 to 70 years [11] or from 20 to 74 years [12]; Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0-2 [11] or 0-1 [12]; estimated life expectancy of more than 3 months; and adequate hematological, renal, and hepatic functions. The presence of a unidimensionally measurable lesion was also required for the phase II studies. Patients with a previous history of chemotherapy (except adjuvant or neoadjuvant chemotherapy not including oxaliplatin or S-1), central nervous system metastasis, obvious bowel obstruction, serous gastrointestinal bleeding, or serious comorbid conditions were excluded from the study. Each patient gave written informed consent before entering the study. The protocol was approved by the institutional review board of each center. www.intechopen.comRectal Cancer -A Multidisciplinary Approach to Management 368 Pretreatment evaluationsBaseline evaluations included medical history, physical examination, ECOG PS, complete blood count with differential count, serum chemistry and electrolytes, urine analysis, and three-dimensional computed tomography. Treatment schemeIn phase I part of the Japanese phase I/II study, oxaliplatin was administered at a dose of 100 mg/m 2 (level 1) or 130 mg/m 2 (level 2) on day 1, and S-1 (40-60 mg) was given twice daily for 2 weeks followed by a 1-week rest [12]. This schedule was repeated every 3 weeks. Level 2 was determined to be the recommended dose (RD) for the phase II part of the study. In two Japanese and Korean phase II studies, oxaliplatin 130 mg/m 2 mixed with 250 mL of dextrose solution was administered intravenously over 2 h on day 1, and S-1 40 mg/m 2 [body surface area (BSA) < 1.25 m 2 , 40 mg; 1.25 ≤ BSA < 1.5, 50 mg; BSA ≥ 1.5, 60 mg] was administered orally, twice daily from day 1 to 14, followed by a 7-day rest period [11,12]. The treatment was repeated every 3 weeks until progression of the disease, the development of unacceptable toxicity, or consent withdrawal by the patient.