Chemoradiotherapy with 5-fluorouracil/leucovorin, surgery and adjuvant chemotherapy for locally advanced rectal cancer.

The aim of this study was to demonstrate a pathologic complete response (pCR) rate of at least 10% with an acceptable toxicity achieved by preoperative chemoradiotherapy with 5-fluorouracil (5-FU)/leucovorin in patients with locally advanced rectal cancer. Patients were treated by radiotherapy targeting 50 Gy and 5-FU/leucovorin intravenously during the 1st, 4th and 7th week after start of radiotherapy followed by surgery and adjuvant chemotherapy. In 71 evaluable patients, the pCR rate was 14.1% (95% CI, 6.0-22.2); the local relapse rate, 6.1%; the 5-year disease-free survival, 54% and the overall 5-year survival, 68%. The most severe adverse events were neutropenia (17%), diarrhoea (17%), infection (8%) and fatal cardiovascular function (1%). This therapy yielded a high rate of pCR, a low rate of local relapse and a long disease-free and overall survival. To increase its feasibility, radiation dose reduction to 45 Gy and administration of only two preoperative cycles of chemotherapy is recommended.