Local excision of distal rectal cancer: An update of cancer and leukemia group B 8984

PURPOSE: The efficacy of local excision in the treatment of some early-stage distal rectal cancers is still being debated, because few high-quality, long-term prospective data on outcomes are available. METHODS: Fifty-nine patients with T1 lesions were treated with local excision alone, whereas 51 patients with T2 lesions received external beam irradiation (5,400 cGY) and 5-fluorouracil (500 mg/m² intravenously Days 1-3, Days 29-31) after local excision. Kaplan-Meier curves were used to estimate the primary outcomes. The log-rank test and Cox's proportional hazards model were used to compare subgroups relative to these outcomes. RESULTS: With a median follow-up of 7.1 (range, 2.1-11.4) years, ten-year rates of overall survival were 84 percent for patients with T1 and 66 percent for T2 rectal cancer. Disease-free survival was 75 percent for T1 and 64 percent for T2 disease. Local recurrence rates for patients with T1 and T2 lesions were 8 and 18 percent, respectively, and rates of distant metastases were 5 percent for T1 and 12 percent for T2 lesions. T stage was a statistically significant predictor of overall survival (P=0.04) and approached statistical significance as a predictor of disease-free survival (P=0.07). CONCLUSIONS: Local excision alone for T1 rectal adenocarcinomas is associated with low recurrence and good survival rates that remain durable with long-term follow-up. T2 lesions treated via local excision and adjuvant therapy are associated with higher recurrence rates.