Pattern and Management of Recurrence of Mid-Low Rectal Cancer After Neoadjuvant Intensity-Modulated Radiotherapy: Single-Center Results of 687 Cases.

BACKGROUND: The purpose of this study was to retrospectively analyze the pattern and the management of recurrence of rectal cancer treated with 22-fraction intensity-modulated radiation therapy (IMRT). PATIENTS AND METHODS: This study included patients who underwent IMRT with gross tumor volume of 50.6 Gy in 22 fractions with concurrent capecitabine treatment over a period of 30 days, after which the patients underwent total mesorectal excision at Peking University Cancer Hospital (2007-2015). Study end points were local recurrence-free survival (LRFS), local disease-free survival (LDFS), disease-free survival (DFS), and cancer-specific survival (CSS). RESULTS: A total of 687 patients were included in our analysis. The median age was 57 years (range, 21-87 years), and 66.4% of the patients were male. The estimated 5-year LRFS and 5-year LDFS rates were 94.4% (95% confidence interval [CI], 92.1%-96.7%) and 96.1% (95% CI, 94.1%-98.1%), respectively. The estimated 3-year DFS and 5-year CSS rates were 77.5% (95% CI, 74.1%-80.9%) and 84.7% (95% CI, 80.9%-88.4%), respectively. Overall, 33.3% of patients (9 of 27) who developed local recurrence, 35.8% of patients (19 of 53) who developed lung metastasis, and 60% of patients (15 of 25) who developed liver metastasis received curative treatment after recurrence. The estimated 3-year survival after recurrence rates of patients who received curative versus palliative treatment were significantly different (87.8% vs. 15.3%, P = .000). CONCLUSION: Rectal cancer treated with the 22-fraction IMRT regimen provides good local control. More than one-fourth of patients who develop recurrence have the chance to receive curative treatment with the incorporation of a multidisciplinary team and achieves excellent survival after recurrence.