We examined 16 patients with rectal cancerwho were preoperatively staged as T3 or T4. The enrolled patients were given 5-FU, 425 mg/m2/day, and leucovorin, 20 mg/m2/day, intravenously for 3 days during weeks 1 and 5 of pelvic radiotherapy. Surgical resection was performed 4~6 weeks after completion of the schedule. Tumor response was divided into CR (complete remission), PR (partial remission), and NR (non remission). Immunohistochemical staining of paraffin sections using monoclonal antibodies for survivin, bcl-2, and p53 was performed on pretreatment biopsy and surgically resected tissue by using the standard avidin-biotin-peroxidasetechnique.