The outcome of 5-fluorouracil chemotherapy after the completion of neoadjuvant chemoradiotherapy, administered until 2 weeks before rectal cancer resection

BackgroundIn most institutions, locally advanced rectal cancer is treated with neoadjuvant chemoradiotherapy followed by surgery 6–8 weeks later, allowing time for tumor response and recovery from chemoradiotherapy-related toxicities. In our hospital, we continuously administer chemotherapy after the completion of chemoradiotherapy, until 2 weeks before surgery for most patients.MethodsThis was a retrospective study. Patients received a diagnosis of adenocarcinoma of the rectum at our hospital between January 2003 and December 2008 and received neoadjuvant chemoradiotherapy and curative surgery. Chemoradiotherapy consisted of continuous infusion of 225 mg/m2 5-fluorouracil, 5 days per week. Radiation therapy was delivered at 1.8 Gy per day, 5 days per week for 5–6 weeks (median radiation dose, 50.4 Gy). Chemotherapy was continued until 2 weeks before surgery, and surgery was performed 6–8 weeks after completion of chemoradiotherapy.ResultsThe study included 119 patients (median age, 61 years; range, 24–84 years). Twenty-nine patients (24.4%) had a complete response and 65 (54.6%) had a partial response. Over a median follow-up duration of 52 months, 10 patients experienced local recurrence and 18 had distant metastasis. The 5-year overall and disease-free survival rates were 80.6% and 72.9%, respectively. Grade 3–4 toxicity only occurred in 14 patients (11.8%).ConclusionContinued chemotherapy with 5-fluorouracil after completing neoadjuvant chemoradiotherapy until 2 weeks before surgery for locally advanced rectal cancer results in a good pathological control rate, with low toxicity. Patients who achieved a complete pathological response had a better long-term oncological outcome than those who did not.