Medium-term results of neoadjuvant systemic chemotherapy using irinotecan, 5-fluorouracil, and leucovorin in patients with locally advanced rectal cancer.

Aims: The aim of this study was to evaluate the usefulness of neoadjuvant systemic chemotherapy using irinotecan, 5-FU, and leucovorin (LV) for the treatment of locally advanced rectal cancer, which was a powerful ploychemotherapy in those days in Japan.

Methods: Between 2001 and 2004, 26 patients with T3 or T4 and N0-2 non-metastatic resectable rectal cancer were selectively enrolled in this study. Neoadjuvant chemotherapy consisted of two cycles of irinotecan (80 mg/m²), 5-FU (500 mg/m²), and LV (250 mg/m²) on days 1, 8, and 15 for 4 weeks. Surgical resection was performed in all the patients 2-4 weeks after the completion of chemotherapy.

Results: Overall down-staging was observed in 15 patients. T level and N level down-staging were observed in 12 and 13 patients, respectively. A pathological complete response was observed in one patients. The median follow-up period was 75 months (range, 8-97 months). Recurrences occurred in 5 patients including pelvic relapses in 3 and distant metastases in 2. The 5-year relapse-free and overall survival rates were 74% and 84%, respectively.

Conclusions: Neoadjuvant systemic chemotherapy comprised of a combination of multi-drugs as irinotecan, 5-FU, and LV may be beneficial to the prognoses of patients with locally advanced rectal cancer.