Raltitrexed plus oxaliplatin in the treatment of metastatic colorectal cancer

Aims and background: As raltitrexed and oxaliplatin (L-OHP) are both effective in the treatment of colorectal cancer but have different mechanisms of action, we studied the antitumoral activity and safety of their combined use in patients with advanced colorectal cancer. Methods: A 15-min intravenous infusion of raltitrexed (2.5 mg/m(2)) and a 180-min infusion of oxaliplatin (100 mg/m(2)) were administered on day 1 every three weeks for a maximum of six cycles. Results: The study involved 51 patients (27 males and 24 females) with a median age of 65 years (range, 43-78); 28 were aged >65 years. The primary tumor site was the colon in 35 patients and the rectum in 16. Thirty-four patients had received prior chemotherapy: 20 as adjuvant treatment and 14 as pre-treatment. The most frequent metastatic sites were liver (18 cases), lung (10 cases), liver + lung (8 cases) and lymph nodes (3 cases). Twenty-four patients completed the entire treatment plan. The most common toxicities were transaminitis (16 patients, grade 3-4), diarrhea (six patients, grade 3), nausea/vomiting (one patient, grade 4), and asthenia (one patient, grade 3). The treatment was stopped in one patient because of prolonged grade 4 transaminitis. The adverse event profile was similar in the patients aged >65 years and <65 years. Complete responses were observed in 2 patients, partial responses in 12, stable disease in 23, and progression in 8. Conclusions: The results of the study suggest that the raltitrexed plus oxaliplatin regimen is feasible and clinically active in advanced colorectal cancer.