Preoperative chemo-radiotherapy in rectal cancer. Effect on down staging and possibility of sphincter sparing surgery

14598 Objectives: To evaluate the influence of pre-operative chemo-radiation on resectability of locally advanced rectal cancer and the possibility of performing sphincter- sparing surgery in cases not suitable for this procedures. Methods: 30 patients with rectal carcinoma with either border line respectability or not suitable for primary sphincter sparing surgery. Performance status > 60, adequate bone marrow reserve and adequate hepatic and renal functions. All patients had been staged by radiological studies and endoscopies. Treatment: All patients were treated by combined chemo-radiation. Radiotherapy with dose of 45 Gray in 25 fractions over 5 weeks. Chemotherapy with 5-flurouracil 500 mg/m2 I.V infusion over 2 hours and leucovorin immediately before radiation setting for first 5 days of the first week and the first 5 days of the last week of radiation. Patients were evaluated 4–6 weeks after treatment. Operable patients were subjected to abdominoperineal resection (APR) or low anterior resection (AR). Toxicity was evaluated using WHO Common Toxicity Criteria. Results: 30 patients were included; the median age was 48 years. Partial response was reported in 63.4% of patients and stable disease was reported in 33.3% of patients while progressive disease was reported in only one patient. Low anterior resection (AR) had been performed in 8 patients out of 12 (66.2%) who had initially not suitable for primary sphincter preservation, while abdominoperineal resection (APR) had been performed in 11 patients out of 18 patients (61.1%) who had initially border line resectability. Tumor down staging was achieved in 66% of patients. Tumor stage was identified as the only significant prognostic factors in response. Local control rate at 18 months were 85%. Actuarial overall survival for patient with curative resection at 18 months, were 85%. Toxicities included G3 leucopenia in 10% of patients, Diarrhea G3 in 13.3% of patients. Conclusion: Preoperative chemo-radiotherapy is an effective treatment in inducing down-staging of locally advanced rectal cancer patients and enhances curative resection and sphincter preserving procedures. Keyword: Colorectal cancer; Chemo- radiotherapy No significant financial relationships to disclose.